Sponge City Hybrid Infrastructure (Earth and Environmental Sciences Library) 3031387651, 9783031387654

Citation preview

Earth and Environmental Sciences Library

Zuzana Vranayova Martina Zelenakova Abdelazim Negm   Editors

Sponge City Hybrid Infrastructure

Earth and Environmental Sciences Library Series Editors Abdelazim M. Negm, Faculty of Engineering, Zagazig University, Zagazig, Egypt Tatiana Chaplina, Antalya, Türkiye

Earth and Environmental Sciences Library (EESL) is a multidisciplinary book series focusing on innovative approaches and solid reviews to strengthen the role of the Earth and Environmental Sciences communities, while also providing sound guidance for stakeholders, decision-makers, policymakers, international organizations, and NGOs. Topics of interest include oceanography, the marine environment, atmospheric sciences, hydrology and soil sciences, geophysics and geology, agriculture, environmental pollution, remote sensing, climate change, water resources, and natural resources management. In pursuit of these topics, the Earth Sciences and Environmental Sciences communities are invited to share their knowledge and expertise in the form of edited books, monographs, and conference proceedings.

Zuzana Vranayova · Martina Zelenakova · Abdelazim Negm Editors

Sponge City Hybrid Infrastructure

Editors Zuzana Vranayova Faculty of Civil Engineering Technical University of Kosice Kosice, Slovakia

Martina Zelenakova Faculty of Civil Engineering Technical University of Kosice Kosice, Slovakia

Abdelazim Negm Water and Water Structures Engineering Department Zagazig University Zagazig, Egypt

ISSN 2730-6674 ISSN 2730-6682 (electronic) Earth and Environmental Sciences Library ISBN 978-3-031-38765-4 ISBN 978-3-031-38766-1 (eBook) https://doi.org/10.1007/978-3-031-38766-1 © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 This work is subject to copyright. All rights are solely and exclusively licensed by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Switzerland AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

Preface

Sustainability is a crucial requirement for new construction projects. This means managing resources such as energy and water responsibly, while also minimizing their consumption. Water is a vital resource that is closely linked to human health, socio-economic prosperity, food production, and the environment. The water-foodenergy nexus highlights the essential role of water in sustaining life on Earth. Despite this, millions of people in developing countries still lack access to sufficient clean water to meet their basic needs. The UN 2030 Agenda’s sixth Sustainable Development Goal, Clean Water and Sanitation, reveals that over 733 million people continue to live in countries facing high or critical levels of water scarcity. With the world’s population growing, particularly in developing countries, it is projected that by 2050, around 64% of people will reside in cities. This urbanization will drive up the demand for water, which has already increased fourfold in the twentieth century. Climate change further exacerbates the situation by intensifying extreme weather events worldwide. This not only affects countries traditionally plagued by water scarcity but also regions with abundant water resources that are often misused or wasted. The World Meteorological Organization reports a 29% increase in droughts since 2000, with 2.3 billion people experiencing water shortages in 2022. It is predicted that by 2050, droughts could impact more than three-quarters of the global population. In contrast, there were 163 annual floods recorded over the last two decades, with a staggering 223 large-scale floods occurring in 2021 alone. Authors from the Faculty of Civil Engineering at the Technical University in Košice, Slovakia including creative staff and doctoral students from the Institute of Civil Engineering and the Institute for Sustainable and Circular Construction, have long been dedicated to developing blue-green infrastructures. As a result of their work on the APVV 18-0360 project, Active Hybrid Infrastructure for a Sponge City, they have decided to share their experiences with a broad professional audience through a scientific monograph titled “Sponge City Hybrid Infrastructure.” The goal of this publication is to introduce the increasingly popular and functional concept of sponge cities, with a focus on sustainable water management in buildings using alternative water sources. In the individual chapters, the authors describe v

vi

Preface

their approaches to achieving this primary objective, especially considering climate change, which has brought about more frequent occurrences of extreme precipitation events and floods, as well as prolonged periods of drought and high temperatures. This research delves into the design and implementation of both passive and hybrid infrastructures, showcasing the real impact of various vegetation structures on buildings and urban areas most affected by climate change. We explore not only new constructions but also the potential for transforming existing buildings into sustainable structures with high-quality indoor environments. As we move towards a future where sustainability indicators for “green buildings” become the norm, our research provides valuable insights into progressive methods of energy management and the use of renewable energy and water resources. These methods are backed by practical studies, offering tangible solutions for a more sustainable future. I would like to express our gratitude to the APVV Agency for their financial support of the APVV-18-0360 project, Active Hybrid Infrastructure for a Sponge City. Our thanks also go to Jaroslav Varga, CSc., the manager of Izola Košice, s.r.o., for his unwavering support and for providing premises for the creation of the GreenIzola Living Laboratory. Finally, we extend our appreciation to all our colleagues from the Faculty of Civil Engineering, TUKE who actively participated in this project. Kosice, Slovakia

Zuzana Vranayova

Contents

State of Art, the Definition of New Concepts of Sponge City and Blue-Green Infrastructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Zuzana Vranayová, Daniela Káposztásová, ˇ and Katarína Lavková Cákyová

1

Sustainable Water Management and Hybrid Infrastructures . . . . . . . . . . Daniela Káposztásová, Zuzana Vranayová, ˇ and Katarína Lavková Cákyová

21

Analysis of Climatic Parameters in Urban Area . . . . . . . . . . . . . . . . . . . . . . Adam Repel, Patrik Nagy, Mária Hlinková, Marcela Bindzárová Gergeˇlová, and Martina Zeleˇnáková

35

Measuring Selected Physical Parameters of Hybrid Infrastructure . . . . . ˇ Marián Vertal, Katarína Lavková Cakyová, and Alena Vargová

53

Prioritization of Sustainability Dimensions and Indicators for Office Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Eva Krídlová Burdová, Silvia Vilˇceková, and Katarína Harˇcárová

83

Development of Hybrid Infrastructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Mária Kocúrková, Pavol Knut, and Alena Vargová Case Studies and Best Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 Danica Košiˇcanová, Alena Vargová, and Martina Zeleˇnáková

vii

State of Art, the Definition of New Concepts of Sponge City and Blue-Green Infrastructures Zuzana Vranayová , Daniela Káposztásová , ˇ and Katarína Lavková Cákyová

Abstract The expansion of city infrastructure is necessary for urbanization, but the excessive development of water infrastructure may lead to water shortages, pollution, and degradation of water ecosystem services. Unscientific architectural planning that results in a high concentration of buildings can also reduce the availability of green space, drainage, and rainwater collection capacity, leading to insufficient rainwater drainage infrastructure and severe problems with water ecology and aquatic environments. The construction of high-intensity artificial features such as roads, buildings, and squares can lead to the hardening of the ground level and alter the natural foundation and hydrological characteristics, causing surface flow to increase (from 10 to 60%) and infiltration to decrease or disappear. As a result, many cities worldwide have experienced frequent flooding in recent decades. In response to these urban water issues, China emphasizes urban flood management and water ecological-system services and supports sponge city development. The traditional grey water management model of fast discharge is no longer sufficient for addressing the rainwater crises caused by rapid urbanization. This chapter aims to introduce the idea of the sponge city as a new urban construction model for water management in sustainable cities and buildings. We will examine issues such as the need to nurture a water saving culture and the use of different alternative water sources such as groundwater, harvested rainwater, reclaimed wastewater and greywater. We will also focus on green roofs and green walls and their main benefits in urban areas.

Z. Vranayová (B) · D. Káposztásová Department of Building Services, Institute of Architectural Engineering, Civil Engineering Faculty, Technical University of Kosice, Kosice, Slovakia e-mail: [email protected] D. Káposztásová e-mail: [email protected] ˇ K. Lavková Cákyová Institute of Architectural Engineering, Faculty of Civil Engineering, Technical University of Kosice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected] © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 Z. Vranayova et al. (eds.), Sponge City Hybrid Infrastructure, Earth and Environmental Sciences Library, https://doi.org/10.1007/978-3-031-38766-1_1

1

2

Z. Vranayová et al.

Keywords Water sources · Sustainable water management · Grey infrastructure · Green and blue infrastructure · Sponge city

1 Introduction Water is the most critical natural resource for this planet in the near future and, if managed properly, can greatly improve the economic situation of nations. Countries could benefit from their past failures to avoid repeating the mistakes made in Europe and around the world during their history. These experiences that have been accumulating for decades should help with the future developments in the water sector. Each country has its own way of water management strategies. Examples of best practices include progressive technological solutions, information sharing, novel institutional set-ups for regulating how the resources are used, and improved cooperation inside and outside the different regions (Water Europe, 2019). The definitions of new widely used words in the concept of sponge city: Biodiversity—The variability among living organisms, including terrestrial and aquatic ecosystems. Biodiversity includes diversity within species, between species, and between ecosystems. Ecosystem services—The benefits for people derived from the functioning of natural ecosystems. Green corridor—A strip of land supports habitat and the movement of wildlife (a vegetated riparian area, a continuous row of street trees or vegetation along a utility easement, etc.). Green infrastructure—An adaptable term used to describe an array of products, technologies and practices which use natural systems—or designed systems which mimic natural processes—to enhance environmental sustainability and quality of life. Includes green and blue infrastructure. Liveability is a broad term encompassing all that contribute to quality of life and make a city enjoyable. Remnant vegetation—Patches of native vegetation/ bushland that can include all forms of vegetation. Resilience—The capacity of a system or city exposed to rise to resist, absorb, prepare, react to the effects of an adverse events in good time and effort manner, establishing a new balance. Urban ecology—The ‘investigation of living organisms in relation to their environment in towns and cities’. The scientific discipline that studies the components of ecosystems situated in urban areas and the interaction between these components. Water Sensitive Urban Design (WSUD)—The ‘capturing of stormwater for local use, which then limits the deterioration of creeks, streams and receiving waters associated with the influx of pollutants from roads, drains and gutters (e.g. sediment, oil, litter). In the UK it is known as Sustainable Urban Drainage Systems

State of Art, the Definition of New Concepts of Sponge City …

3

(SUDS), in the US as Low Impact Development (LID) and in China as Sponge Cities. It means other design approaches that enhance waterways’ health and their ecological communities. Urban green cover—The integration of vegetation with permeable and reflective surfaces to minimise local temperatures and encourage evaporation from soil and plants into the urban environment. It includes a broad range of strategies such as green open space, green streets, green walls and green roofs. Urban renewal or urban regeneration—Redevelopment of land in medium to high density areas. This is typically in the inner and middle ring suburbs and may involve changing the use of land (e.g. from industry to residential, changing the density or construction of new infrastructure) (EPA, 2023).

2 Water Saving Culture 2.1 Freshwater Sources It is well known that our world is mostly covered in water, but not precisely what proportion of our planet is made up of water. Water makes up about 70% of the Earth’s surface, but around 97% of the Earth’s water is stored within the oceans and seas, and only the remaining 3% is freshwater located in lakes and frozen water in glaciers. It is estimated that all the Earth’s freshwater would measure some 1386 million km3 in volume if taken as a single mass (Shiklomanov, 2011). While there will always be plenty of water in the world, the amount of usable freshwater that is easily accessible is rapidly shrinking due to a few key factors: – Population growth; it is predicted that the human population will reach 10 billion by the end of the century. – One billion people already suffer from a lack of access to water. – Water that could be used for drinking is contaminated with microbial toxins, viral infections, and chemicals such as pesticides and manufacturing waste. (NizaRibeiro, 2022).

2.2 Water Stress and Day Zero The situation where the water consumption by people and environment are so high, that there isn’t enough water of sufficient quality available to meet their demand is called water stress—and is already happening in parts of Europe. About 30% of Europeans are affected by droughts and water scarcity, which are happening more often than in the past. About 20% of the European landmass experiences water stress during an average year (EEA, 2022). More details about the current situation in Europe and Slovakia can be found in Chapter “Analysis of Climatic Parameters in Urban Area”.

4

Z. Vranayová et al.

Climate change adverse impacts are increasing the drought’s frequency, magnitude and incidence. As these trends can be predominantly seen in southern and southwestern Europe where agriculture, public water supply and tourism place substantial pressure on water availability with a significant seasonal peak in summer, Slovakia is not yet in such a difficult situation (EEA, 2022). Generally, it seems that strengthening resilience in European cities requires a combination of various approaches, including partnerships, sustainable development, and climate action. To minimize the impacts of water stress by using water more efficiently means a combination of technological, policy, and behavioral changes that consider the unique challenges and resources of each region. Only a few years ago our continent edged dangerously close to the situation called “Day Zero”—the moment when the fresh water in the city would need to be rationed. This existential crisis was triggered by a severe and unanticipated drought that turned all the local reservoirs into dustbowls. This usually happens in cities outside Europe or only the largest cities. In May 2023 Barcelona is heading for a ‘drought emergency’ as water shortages worsen according euronews (Green News, 2023). Cities most at risk of Day Zero (Aid, 2022): . . . . . . . . . . . . . .

Cape Town, South Africa Roma, Italy Mexico City, Mexico Cairo, Egypt Tokyo, Japan Jakarta, Indonesia São Paulo, Brazil Beijing, China Bangalore, India Melbourne, Australia London, United Kingdom Moscow, Russia Istanbul, Turkey Miami, Florida, United States

The effects of climate change in Slovakia exceeded their predictions in terms of frequency as well as intensity. In the years 2001 to 2017, there were impacts that were originally predicted up to for the year 2030 (Ministry of the Environment of the Slovak Republic, 2017). It is expected that average air temperatures will gradually increase by 2 to 4 °C compared to averages over the years 1961–1980 (Ministry of the Environment of the Slovak Republic, 2018).The higher air temperatures (Ministry of the Environment of the Slovak Republic, 2018), decrease in total precipitation in the south and increase in the north of the country, decrease in relative humidity to southern Slovakia and reduction of snow cover in places up to 1000 m above sea level. m. Since year 1993 gradual desertification occurs mainly in the south due to long dry periods with very low rainfall during the growing seasons (Ministry of the Environment SR, 2017). In addition, the occurrence of heat waves as well as cold

State of Art, the Definition of New Concepts of Sponge City …

5

waves has increased. It is a significant assumption that the situation will continue to deteriorate. The problem of Day Zero is a growing concern for many cities around the world, and it highlights the need for sustainable water management practices to ensure a reliable and secure water supply for future generations.

2.3 Water Consumption vs. Water Price Household water consumption and water prices differ greatly from country to country. Statistics for different European countries can be found in the European Federation of National Associations of Water Services—The governance of water services in Europe. Figure 1 shows that only four countries exceed the average of 150 L per person per day. The extremes seen in the graph are Switzerland with 300 L of water per person/day vs. 78 L in Slovakia and Malta. Other countries have between 80 to 150 L per person per day. Generally, Eastern European countries are the ones with lowest water consumption. In fact, there seems to be a gradient from eastern to western Europe, from lower to higher consumption (EurEau, 2020). There is a large variability in the average price of water for households in European countries as we can see in Fig. 2. The highest price can be seen in Denmark with 9.32 e/m3 , followed by Norway with 7.8 e/m3 . Slovakia is in under the middle of the ranking, with an average price of 2.5 e/m3 . Another study conducted in 2021 (WNE, 2021) shows a comparison of water prices in 36 EU-cities, with the tap water

Household water consumption

Litres per person and day

350 300 250 200 150 100 50

Switzerland Italy Portugal France Greece Croatia Sweden Norway Cyprus UK Luxembourg Spain Ireland Austria Netherlands Germany Romania Finland Denmark Slovenia Poland Bulgaria Hungary Belgium Czechia Estonia Malta Slovakia

0

Fig. 1 Water consumption per household in EU countries (authors library; based on EurEau, 2020)

6

Z. Vranayová et al.

Average water price 10

€ per cubic metre

9 8 7 6 5 4 3 2 0

Denmark Norway Luxembourg Finland Netherlands Switzerland Belgium Sweden France Austria UK Czechia Malta Estonia Poland Slovakia Slovenia Hungary Italy Croatia Spain Portugal Cyprus Romania Greece Bulgaria Ireland

1

Fig. 2 Average water price in EU countries (authors library; based on EurEau, 2020)

price in Oslo being the highest at 5.51 euro for 1.000 L (1 m3 ) of drinking water, and the cheapest being in Naples, Italy at 1.42 euro for the same amount of water. We see even if Greece (1.23 e/m3 ) and Bulgaria (1.07 e/m3 ) are among the countries with the cheapest water in Europe, the price of water in Ireland for example is not directly collected from consumers (although what is not collected directly has to be financed through taxes), and the price of bottled water in Greece is not directly related to the price of tap water. The hypothesis that the low-price result in higher consumption is contradicted in case of Ireland, as figures show lowest price but only medium consumption ranking for the country (EurEau, 2020).

2.4 Water Saving Measures Water consumption varies based on use of appliances and personal preferences. As water resources become scarcer, the cost of building new infrastructure to meet growing demand becomes increasingly high. If we choose instead to save water, we can offset the need for new infrastructure and reduce the pressure on existing facilities. Additionally, efficient water use makes our supply more resilient against impacts from climate change, such as droughts. There are various ways to reduce the amount of water consumed at a facility, such as installing low-flow plumbing fixtures, regulating water pressure, insulating piping, and optimizing cooling tower efficiency. However, one of the simplest and most cost-effective strategies is to obtain the participation of other residents in water

State of Art, the Definition of New Concepts of Sponge City …

7

conservation programs, even though it is not a design specification or technology option. This method is a keyway to achieve water use reduction goals. According EPA studies (EPA, 2021) more than half of the potable water currently used in the building water cycle could be replaced by non-potable water. This can be achieved through the reuse of alternative water sources. The five “R” principle for water efficiency in buildings. All interventions which contribute to the more efficient use of water in buildings can be systematized by a guiding rule called “the 5R principle” which Carla Pimentel-Rodrigues and Armando Silva-Afonzo developed. – The 1st R—Reduce consumption; steps include the adoption of efficient products and devices, which can supplement other measures of an economic, fiscal or sociological nature. For this purpose, labelling the water efficiency of products similar to existing strategies to promote energy efficiency should be considered an essential measure for providing information to consumers. – The 2nd R—Reduce losses and waste; this can involve monitoring losses in building networks (for example, in flushing cisterns or sprinklers) or installing circulation and return circuits for sanitary hot water. – The 3rd and 4th R—Re-use and recycle grey water/wastewater, meaning “series”-based use or the re-introduction of water at the start of the cycle after treatment. This can be relevant in relation to the use of grey water, not excluding the possibility of using treated wastewater for some purposes, such as watering gardens. – The 5th R—Resort to alternative sources. This can involve the use of rainwater, groundwater and salt water. These measures can be easily considered for either new or refurbished buildings. Water efficiency audits and risk management methods are a more appropriate procedure for existing buildings, as is also the case with energy efficiency (Silva-Afonso & Rodrigues, 2008; Káposztásová, 2015).

2.5 Sources of Water at the Building Level Water exists in many different forms and Kinkade-Levarios (2007) has defined the following types: . . . . . . . . .

Atmospheric water—in the form of rain and fog Blue water—water contained in lakes and rivers Green water—water contents of soil moisture and plants Stormwater—rainwater that has reached the ground Grey water—light and dark wastewater from appliances as washing machines, bathtubs, showers, and hand basins Alternate water—water that has been used previously Black water—water from toilets and kitchen sinks Reclaim water—water that has gone through a sewer treatment process and has been filtered and processed for reuse in various ways Sea water—water obtained from desalination of seas and oceans

8

Z. Vranayová et al.

Water types that are the most common and available source of water in buildings: . Potable water—tap water, a source of water for potable purposes . Water from wells—this water can be a source of water for either potable or nonpotable purposes . Rainwater—water collected from the roof during precipitation, a source of water for non-potable purposes . Grey water—wastewater from bathtubs, showers, hand basins, a source of water for non-potable purposes (Silva-Afonso, 2011). When considering alternative water supplies, we should choose the most appropriate water source for the intended purpose. More details can be found in Chapter “Sustainable Water Management and Hybrid Infrastructures” and (Káposztásová, 2015).

2.5.1

Water from Wells

Like surface water, groundwater could be a resource for potable water. It is an important part of the water cycle but, like other water resources, it can be affected by drought and changes in climate. Groundwater is accessed by digging a hole into the ground to create a well; a pump is then used to supply fresh water from the well to residences. Wells have been used for generations and are an efficient way of providing access to water in almost every region of the world.

2.5.2

Rainwater

Capturing rainwater from roofs is an excellent way of supplying water for a wide range of applications including washing clothes, flushing toilets, and watering greenery. Accumulation of rainwater into tanks can also help reduce water bills, if the tanks are combined with other devices used for water-saving (e.g. dual-flush toilets, waterefficient showerheads, trigger nozzles and tap timers). Up to 40,000 L of water per year can be saved this way per household.

2.5.3

Greywater

Greywater is recycled water from domestic uses in the home. It includes water from baths, showers, hand basins, and washing machines. Greywater from the kitchen (including water from dishwashers) should not be used, because it contains food wastes and chemicals, which are not easily degraded in the soil. While the use of greywater can help to keep gardens thriving during

State of Art, the Definition of New Concepts of Sponge City …

9

periods of low rainfall, it is essential to be aware of how this type of water can affect homes, gardens and the local environment. Suppose greywater is not used in a correct manner rightly. In that case, it can in fact harm the soil and plants, with the worst case scenario of becoming a health risk for users and their pets due to the unwanted adverse effects of chemicals and bacteria it contains.

2.5.4

Hybrid Systems

Very often, rainwater and greywater sources are insufficient to meet the water demand in a building. In such cases we can effectively combine rainwater, greywater, water from wells, and tap water to cover the entire water demand at the building level and to make transition from a grey house to a blue house. The hybrid system represents the vision of the building water cycle. The potential uses for grey and rainwater depend on the quantity and quality of water available. Each case must be assessed using an individually tailored plan to design the most efficient and green sustainable water system possible. When we use alternative water sources, our priority is to protect the users as well as the environment. The risk management approach is the best way to achieve this target. The water quality is important and the intended end use depends on it. We can therefore see that sustainable water management can be defined as a system of water resource management that meets the needs of both present and future generations. A “net-zero” water building is an innovative strategy that pushes the buildings to be fully self-sufficient in generating their potable water needs and treating all discharged waste.

3 Sponge City 3.1 A New Model of Complex Urban Construction—Sponge City Sponge city is a new urban construction model (Fig. 3) proposed by Chinese researchers in early 2020 (Gies, 2018; Wong, 2021) and intended to facilitate flood management and strengthen ecological infrastructure and drainage systems. The concept can alleviate urban flooding, water shortages the effect of urban heat island, and improve the ecological environment and biodiversity by absorbing and retaining rainwater. Rainwater harvested in this way can be repurposed for irrigation, home use, and flood reduction risk. Therefore, the sponge city is a form of sustainable drainage system which can be implemented on an urban scale and beyond. Sponge city policies are a set of nature-based solutions that use natural landscapes to catch,

10

Z. Vranayová et al.

Fig. 3 Sponge city vision (created by AI)

store and clean water. The concept was inspired by the ancient wisdom of adaptation to climate challenges, particularly in regions that experience monsoon seasons. China has been a prominent adopter of the sponge city initiative and the concept is the result of persistent efforts by Chinese ecological urbanists who were motivated by the failure of the conventional grey infrastructure of flood control and storm water management systems. Though the study introducing the concept was first published in early 2000, it was the Beijing floods of 2012, a disaster which caused 79 deaths, that prompted the Chinese authorities to accept the sponge city concept at the highest levels of government and introduce it as a nationwide policy. In 2015, China was reported to have initiated a pilot initiative in 16 districts (Xiang et al., 2019). This initiative is presented by China as an alternative solution to the problem of flooding across Asia. The Chinese government has set an ambitious target, mandating that 80% of its urban cities should harvest and reuse 70% of their rainwater. Although the construction of sponge cities does not necessary require huge investments, many media outlets have published misleading information on the topic. The sponge city concept is often misused by local government, contractors and unprofessional designers as a fashionable brand and slogan which has little to do with the real aims and values of this nature-based solution. The biggest drawback to implementing the nature-based sponge city is the outdated approach and “business as usual” thinking of grey infrastructure engineering, conventional urban planning, and the legislative systems introduced to defend these obsolete urbanism practices. Finding sufficient financial support for sponge cities has also been a challenge. After achieving success in China, the sponge

State of Art, the Definition of New Concepts of Sponge City …

11

Table 1 Comparison of terms commonly used around the world (according to Fenner, 2017) Term

Short definition

Blue green city

– refers to natural and engineered systems that use vegetation, soil, and other elements to manage water and provide other environmental benefits

Sponge city

– is an urban construction model that uses natural and ecological methods to manage water sustainably, alleviate flooding problems, and reduce the damage to urban infrastructure caused by waterlogging. The concept is based on managing water in an ecologically sustainable way, allowing water to permeate, flow into runoff capture systems, and be collected and reused

Water sensitive urban design

– encompasses all aspects of integrated urban water management and is significant shift in the way water related environmental resources and water infrastructure are considered in the planning and design of cities, at all scales and densities

city model has is becoming an attractive option for other countries in over-exposed climate zones such as Dhaka and Kenya, and for major cities such as Berlin and Los Angeles. Water-sensitive urban design (WSUD) is another closely related land planning and engineering design approach that integrates the urban water cycle, including the management of stormwater, groundwater and wastewater and water supply, into urban designs. To reduce the negative impact on the environment and enhance the visual and recreational appeal, WSUD is a term used in Australia and the Middle East. This approach is similar to LID—Low Impact Development, which is used in the United States, and SuDS—Sustainable Urban Drainage Systems, which is used in the United Kingdom (refer to Table 1) (Fenner, 2017; Yang et al., 2022; Yin et al., 2022).

3.2 A Sponge City Principles and Components The sponge city philosophy is based on the principles of distributing and retaining water at its source, slowing down water as it flows away from its source, cleaning water naturally and adapting to water at the sink when water accumulates. This approach starkly contrasts the conventional solution of grey infrastructure, in which water is centralized and accumulated in large reservoirs by maximising water flow to pipes and channelized drains and combatting water at the end stage with higher and stronger flood walls and dams. (Yang et al., 2022; Yin et al., 2022). The sponge city theory highlights the fundamental principles of being based on nature, controlling sources, adapting locally, protecting nature, learning from nature, preserving urban ecological space as much as possible, restoring biodiversity, and creating a beautiful landscape and environment (Yawen et al., 2020). This can be achieved through approaches that emphasise natural absorption, natural infiltration, and natural purification. These principles are derived from long-standing wisdom and

12

Z. Vranayová et al.

strategies which have been practiced across China for thousands of years, in times when people were forced to adapt to water events rather than attempting to combat them with grey infrastructure (Ma & Jiang, 2022). Sponge cities use a combination of natural and artificial means to absorb and release rainwater. The natural ecology’s infiltration effects, such as topography and landforms, combined with the purification effect of vegetation and wetlands on water quality, allow cities to absorb and release rainwater. Urban green spaces and bodies of water, such as constructed wetlands, rain gardens, green roofs, recessed green spaces, grass ditches, and ecological parks, serve as the primary “sponge bodies.” The sponge city indicates a particular type of city that does not act like an impermeable system preventing water from filtering through the ground but instead behaves more like a sponge. Such cities absorb rainwater, allowing it to be filtered naturally by the soil and reach the urban aquifers. This allows for the extraction of water from the ground through urban or peri-urban wells which can be easily treated and used for the city water supply (Yang et al., 2022; Yin et al., 2022). A sponge city must be abundant with spaces allowing water to seep through them. The city should implement the following strategies to manage water resources and reduce the impact of stormwater run-off: . Develop contiguous open green spaces, interconnected waterways, channels and ponds that can naturally detain and filter water, foster urban ecosystems, boost biodiversity, and provide cultural and recreational opportunities. . Implement green roofs that retain rainwater and naturally filter it before it is recycled or released into the ground. . Introduce porous design interventions such as bio-swales and bio-retention systems to detain run-off and allow for groundwater infiltration. . Construct porous roads and pavements that can accommodate car and pedestrian traffic while allowing groundwater absorption, percolation, and replenishment. . Implement drainage systems that absorb water into the ground or direct stormwater run-off into green spaces for natural absorption. . Promote water savings and recycling, including the extension of grey water recycling at the level of individual residential buildings. . Incentivize consumers to save water through increased high-consumption tariffs, awareness raising campaigns, and the introduction of improved smart monitoring systems to identify leakages and inefficient water usage. Nguyen et al. published a review article on the implementation of sponge city, which outlined the concept of sponge city as well as its limitations and opportunities (Nguyen et al., 2019).

3.3 Sponge City Benefits There are many benefits to implementing sponge cities, including:

State of Art, the Definition of New Concepts of Sponge City …

13

. Improved access to clean water for the city through replenished groundwater, leading to greater water self-sufficiency and reliance on local water sources. . Cleaner groundwater due to the increased volume of naturally filtered stormwater, resulting in reduced water pollution, and associated environmental and health costs. . Reduced flood risk as the city provides more permeable spaces for the natural retention and percolation of water, improving resilience and the ability to handle higher flood risks due to climate change. . Reduced burden on drainage systems, water treatment plants, artificial channels, and natural streams, as well as lower costs for drainage and treatment infrastructure. . More attractive and enjoyable urban spaces with increased greenery, improved quality of life, and increased land value due to the presence of aesthetically pleasing, clean, and healthy open spaces near private properties. . Enhanced biodiversity around green open spaces, wetlands, urban gardens, and green rooftops.

4 Green Infrastructure Green Infrastructure is a network of natural and semi-natural areas, features, and green spaces in rural and urban, terrestrial, freshwater, coastal, and marine areas. It enhances ecosystem health and resilience, contributes to biodiversity conservation, and benefits human populations by maintaining and enhancing ecosystem services. Strategic and coordinated initiatives can strengthen it by maintaining, restoring, improving, connecting existing areas and features, and creating new ones. It is a water management approach that mimics, restores or protects the natural water cycle. According to Naumann, the term “Green Infrastructure” describes the network of natural landscape assets which underpin the economic, socio-cultural and environmental functionality of our cities and towns. Individual components of this environmental network are sometimes referred to as “Green Infrastructure assets”, and these occur across a range of landscape scales. For example, from residential gardens to local parks and housing estates, streetscapes and highway verges, services and communications corridors, waterways and regional recreation areas (AILA, 2012; Pitman, 2015a, 2015b). Green buildings (GBs) play an important role in green infrastructure. GBs is the practice of creating structures and using processes that are environmentally responsible and resource-efficient throughout a building’s lifecycle, see Fig. 4 (EPA, 2021; USGBC, 2023). Green buildings help reduce negative impacts on the natural environment by using less water, energy, and other natural resources; employing renewable energy sources and eco-friendly materials; and reducing emissions and other waste. They promote resilience-enhancing designs, technologies, materials, and methods and can even provide net-positive impact in terms of generating energy and reducing

14

Z. Vranayová et al.

Fig. 4 Green building and its impact on other spheres (authors library; based on Cole, 2019)

waste. Green buildings are a global solution for cities, communities, and neighborhoods. This concepts extend beyond the walls of buildings and include site planning, community, and land-use planning issues as well it is an important aspect of green infrastructure, which aims to create sustainable and resilient communities that are environmentally responsible and resource-efficient. However, even green buildings have their advantages and disadvantages. On the one hand, they can bring long-term economic benefits to owners and create a healthy and pleasant indoor environment for occupants. On the other hand, the initial costs of building and implementing green technologies can be high, the availability of certain materials or technologies may be limited, and the savings and returns may prove to be poorly estimated. In addition, the effectiveness of green building strategies may depend on factors such as climate, location and building. Overall, green building in green infrastructure can provide significant economic benefits, making it a smart investment for building owners and communities alike. The US Green Building Council reports that operating cost savings, shorter payback periods, and increased asset value in new green buildings and green retrofits have been consistently reported. Building owners have seen a 10 percent or greater increase in asset value, making upfront investment in green building a smart investment (USGBC, 2023).

State of Art, the Definition of New Concepts of Sponge City …

15

4.1 Green Roofs and Green Walls in Urban Areas Green roofs (also known as living roofs or eco-roofs) are roofs or decks designed to feature vegetation or provide wildlife habitats (Rowe, 2011) Green and blue roofs improve water quality and save energy by providing insulation that reduces cooling and heating costs. These roofs also manage stormwater in urban areas by retaining rainfall and reducing city runoff. Additionally, green roofs sequester carbon pollution and retain a significant portion of the rain that falls on them, releasing the water at a slower rate and reducing the amount of runoff entering the watershed.

4.1.1

Types of Green Roofs

Green roofs can be categorized into several types based on their depth, irrigation, maintenance requirements, and other features. Extensive green roofs are shallow, typically 40 mm to 150 mm deep, and are usually vegetated with low-growing, drought-tolerant plants such as stonecrops (Sedum species) and dry meadow vegetation. They are low maintenance, often not requiring irrigation (except during the planting process) and have a simple design. Intensive green roofs, also known as roof gardens, are deeper, with soils ranging from 200 mm or more in depth, and are often irrigated and require regular maintenance. They are designed to create a formal landscape such as a garden or park on a roof or podium and may be necessary for urban food production. Biodiverse green roofs are specifically designed to provide a particular native vegetation type or habitat for specific species of wildlife, while semi-intensive roofs are a combination of different types, typically with deeper soils, a variety of plant types, and the ability to be either irrigated or unirrigated. Biosolar roofs are extensive green roofs that are combined with photovoltaic arrays, resulting in increased efficiency for both the green roof and the PV array. Blue green roofs store rainwater and act as a source-control feature in a sustainable drainage system, while blue roofs (which are not technically green infrastructure) use detention ponds to collect and store rainfall before draining it into waterways and sewers at a controlled rate.

4.1.2

Types of Green Walls

Green façades are walls with climbing plants rooted in the ground or in planter boxes. These plants can be trained against wires or trellises and may take some time to establish but have low maintenance requirements and may not require irrigation if rooted in the ground.

16

Z. Vranayová et al.

Living walls are proprietary systems with textiles, plastics, metal pockets, or troughs supporting plants. These systems may be soil-based or soil-free and are typically irrigated using pumps or moisture sensors. Passive living walls, also known as vertical rain gardens, use water wicks or seepage to irrigate planters from tanks that collect rainwater from roofs. Bioactive façades are made of building materials with surfaces designed to support self-sustaining vegetation like algae and moss, creating low-maintenance green walls in areas where more heavily vegetated systems are not feasible. Smart green roofs have sensors and software that allow stored water to be discharged at slower rates to maintain an irrigation reservoir or emptied in advance of heavy rain to maximize water storage.

4.1.3

Benefits of Green Infrastructures

Green Infrastructure can take a number of forms and can provide a wide range of what are known as Ecosystem Services (Niza-Ribeiro, 2022; Kolasa-Wi˛ecek & Suszanowicz, 2021). Some of the ecosystem services that can be provided by Green Infrastructure include the following: . Social; Human health and well-being. – Physical. – Social and psychological. – Community. . . . . . . . .

Cultural. Visual and aesthetic. Economic. Commercial vitality. Increased property values. Value of ecosystem services. Environmental. Climatic modification. – Temperature reduction.

. Shading. . Evapotranspiration. – Wind speed modification. . Climate change mitigation. – Carbon sequestration and storage and avoided emissions (reduced energy use). . Air quality improvement. – Pollutant removal and avoided emissions.

State of Art, the Definition of New Concepts of Sponge City …

17

. Water cycle modification. – Flow control and flood reduction. . Canopy interception. . Soil infiltration and storage. – Water quality improvement. . Soil improvements. – Soil stabilization; increased permeability and waste decomposition and nutrient cycling. . Biodiversity. – Species diversity; habitat and corridors. . Food production: Productive agricultural land and urban agriculture. For more details about parameters, their measurement and analysis see Chapters “Measuring Selected Physical Parameters of Hybrid Infrastructure” and “Prioritization of Sustainability Dimensions and Indicators for Office Buildings”. For more information about design and realisation of new progressive hybrid infrastructure see Chapters “Sustainable Water Management and Hybrid Infrastructures” and “Development of Hybrid Infrastructures”. Other important related topics, such as flood and drought risk assessment, best practices for the natural water retention designs, current sustainable water conservation and flooding measures tested in our experimental labs and implemented in cities worldwide, are also discussed in following Chapters “Analysis of Climatic Parameters in Urban Area” and “Case Studies and Best Practices”. The multifunctionality of green infrastructure can be inferred in many current cases, and knowing the relationship between design features and their benefits for green infrastructure would facilitate selecting optimal design features to achieve specific goals and planning outcomes.

5 Conclusions Incorporating sponge city elements into the planning of urban development land can effectively balance stormwater management and land utilization in urban planning, while also achieving a balance between the development of individual districts and the protection of the urban watershed environment. Growing concerns about water security, water ecology, and water quality are putting pressure on traditional gray engineering infrastructure. While sponge city construction (which includes green infrastructure) can alleviate some of this pressure, traditional gray infrastructure is still essential for safety during extreme storms. To avoid excessive artificial interference with the ecological environment, it is important

18

Z. Vranayová et al.

to carefully control the scale of grey infrastructure in sponge city construction. Both green and grey infrastructure should be integrated effectively in urban water system management. Acknowledgements The authors are grateful for the support of the Slovak Research and Development Agency APVV-18-0360 “Active hybrid infrastructure towards to a sponge city”.

References Aid, Ch. (2022). Scorched earth: The impact of drought on 10 world cities. Posted 18 May 2022. Australian Institute of Landscape Architects. (2012). Green Infrastructure Report AILA. Cole, L. B. (2019). Green building literacy: A framework for advancing green building education. International Journal of STEM Education, 6, 18. https://doi.org/10.1186/s40594-019-0171-6 Environmental Protection Agency—EPA. (2021). Fit-for-purpose water updates and life cycle comparisons of non potable water reuse scenarios—YouTube. https://www.youtube.com/watch? v=5pDHJD9FDxQ EPA. (2023). https://www.epa.gov/environmental-topics/greener-living Euronews with AP & AFP. (2023). Barcelona is heading for a ‘drought emergency’ as water shortages worsen. https://www.euronews.com/green/2023/04/19/. Updated: 27 April 2023. Fenner, R. (2017). Spatial evaluation of multiple benefits to encourage multi-functional design of sustainable drainage in blue-green cities. Water, 9, 953. https://doi.org/10.3390/w9120953 Gies, E. (2018, December). Sponge cities can limit urban floods and droughts. Scientific American, 319(6), 80–85. Káposztásová, D. (2015). Integrated water management at the building level, Habilitaton work, Technical University of Kosice. Kinkade-Levario, H. (2007). Design for water. New Society Publisher, 240 p. ISBN: 9781550923407. Kolasa-Wi˛ecek, A., & Suszanowicz, D. (2021). The green roofs for reduction in the load on rainwater drainage in highly urbanised areas. Environmental Science and Pollution Research, 28, 34269– 34277. https://doi.org/10.1007/s11356-021-12616-3 Ministry of Environment of the Slovak Republic. (2017). The seventh national communication of the Slovak republic on climate change. Ministry of the Environment of the Slovak Republic. (2018). Climate change adaptation strategy, update. Nguyen, T. T., Ngo, H. H., Guo, W., Wang, X. C., Ren, N., Li, G., Ding, J., & Liang, H. (2019). Implementation of a specific urban water management-Sponge City. Science of the Total Environment, 652, 147–162. https://doi.org/.10.1016/j.scitotenv.2018.10.168 Niza-Ribeiro, J. (2022). One health chapter 5. Food and water security and safety for an everexpanding human population. In Integrated Approach to 21st Century Challenges to Health 2022 (pp. 155–204). Pitman, S., Daniels, Ch., & Ely, M. (2015a). Green infrastructure as life support: Urban nature and climate change. Transactions of the Royal Society of South Australia, 139(1), 97–112. https:// doi.org/10.1080/03721426.2015.1035219 Pitman, S. D., Daniels, Ch. B., & Ely, M. E. (2015b). Green infrastructure as life support: Urban nature and climate change. Transactions of the Royal Society of South Australia. https://doi.org/ 10.1080/03721426.2015.1035219 Rowe, D. B. (2011). Green roofs as a means of pollution abatement. Environmental Pollution, 159(8–9), 2100–2110. https://doi.org/10.1016/j.envpol.2010.10.029

State of Art, the Definition of New Concepts of Sponge City …

19

Schindler, B. Y., Blaustein, L., Lotan, R., Shalom, H., Kadas, G. J., & Seifan, M. (2018). Green roof and photovoltaic panel integration: Effects on plant and arthropod diversity and electricity production. Journal of Environmental Management, 225, 288–299. Shiklomanov, I. (2011). World freshwater resources chapter in water in crisis: A guide to the world’s fresh water resources. Oxford University Press. https://doi.org/10.1016/j.rser.2018.04.006 Silva-Afonso, S. (2011). Grey water in buildings: The Portuguese approach. In Proceedings of 37th international symposium CIB W062 on water supply and drainage for buildings, Aveiro. Silva-Afonso, A., & Rodrigues, C. (2008). Water efficiency of products and buildings: The implementation of certification and labelling measures in Portugal. In Proceedings—CIB W062 2008—34th international symposium of water supply and drainage for buildings. HKPU. Susca, T., Gaffin, S. R., & Dell’Osso, G. R. (2011). Positive effects of vegetation: Urban heat island and green roofs. Environmental Pollution, 159(8–9), 2119–2126. https://doi.org/10.1016/j.env pol.2011.03.007 The EEA Report. (2022). Water resources across Europe—Confronting water stress: An updated assessment. Published 27 October 2021. Last modified 27 October 2021. https://www.eea.eur opa.eu/highlights/water-stress-is-a-major USGBC (2023). U.S. Green Building Council. https://www.usgbc.org/. Accessed 20 February 2023. Water Europe. (2019). Water in the 2030 agenda for sustainable development: How can Europe act? Water Europe. Water News Europe. (2021). Water prices compared in 36 EU-cities. https://www.waternewseur ope.com/water-prices-compared-in-36-eu-cities/ Wong, T. (2021). The man turning cities into giant sponges to embrace floods. BBC News. https:// www.bbc.com/news/world-asia-china-59115753 Xiang, Ch., Liu, J., Shao, W., Mei, Ch., & Zhou, J. (2019, February 1). Sponge city construction in China: Policy and implementation experiences. Water Policy, 21(1), 19–37. https://doi.org/10. 2166/wp.2018.021 Yang, D., Zhao, X., & Anderson, B. C. (2022). Integrating Sponge City requirements into the management of urban development land: An improved methodology for Sponge City implementation. Water, 14, 1156. https://doi.org/10.3390/w14071156 Yawen, W., Jun, L., Haowen, X., Guangyuan, Y., Hong, Z., Yichen, Y. (2020, August 1). Towards government mechanisms of sponge city construction in China: Insights from developed countries. Water Policy, 22(4), 574–590. https://doi.org/10.2166/wp.2020.155 Yin, D., Xu, C., Jia, H., Yang, Y., Sun, C., Wang, Q., & Liu, S. (2022). Sponge City practices in China: From pilot exploration to systemic demonstration. Water, 14, 1531.

Sustainable Water Management and Hybrid Infrastructures Daniela Káposztásová , Zuzana Vranayová , ˇ and Katarína Lavková Cákyová

Abstract Hybrid infrastructures are challenges that we have started to face recently. Climatic changes caused by human activity are major reasons for transformation need. Green infrastructure is a key strategy to provide clean air and water, while improving living conditions and human health. It is effective, economical, and enhances quality of life. This chapter presents some interesting results of 5 questionnaires completed from 2010 to 2023 that focused on rainwater harvesting systems, grey water use risk analysis, respondent’s general overview about the green walls, green wall/roof effect on respondent, ecology/air quality and respondent’s opinion, sustainable water use, water habits the last one, in 2023, was aimed at respondents’ knowledge about sustainable water use, sponge city and hybrid infrastructures in urban areas. The main goal was to find out how people’s awareness about sustainable water management and hybrid infrastructures had changed during the last few years in Slovakia. People expect to have safe water and sanitation; therefore, when recycling water, it is essential to protect public health and the environment. One of the foundations of creating healthy and sustainable buildings points to need to hygienically ensure water and air distribution so that they do not become a threat to the people. The future will require skillful and creative stewardship of our most vital natural resource, as well as innovative approaches to hybrid infrastructures to keep water infrastructure strong and resilient. Keywords Water · Questionnaire · Hybrid infrastructure · Sustainable solutions · Slovakia ˇ K. Lavková Cákyová Institute of Architectural Engineering, Faculty of Civil Engineering, Technical University of Kosice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected] D. Káposztásová (B) · Z. Vranayová Department of Building Services, Institute of Architectural Engineering, Faculty of Civil Engineering, Technical University of Kosice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected] Z. Vranayová e-mail: [email protected] © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 Z. Vranayova et al. (eds.), Sponge City Hybrid Infrastructure, Earth and Environmental Sciences Library, https://doi.org/10.1007/978-3-031-38766-1_2

21

22

D. Káposztásová et al.

1 Introduction One of five critical drivers that will influence progress toward a sustainable and resilient water future is sustainability (AWWA, 2022). Sustainability is a term that can be defined in many ways and has different meanings for different people. One of the most used definitions is the “Our common future” report, also known as the Brundtland report (United Nations, 1987). Sustainable water management is a relatively new concept that has become increasingly viewed as necessary investing in a resilient future for our cities. The human health dimension as a very important part of sustainability is facing many challenges. To achieve balance with nature and address problems arising from climate variability, environmental risks, urbanization and energy consumption, we need to change the way society thinks (Egerer et al., 2021). The need for new technologies, approaches and solutions is highlighted by problems such as rapid rainfall and drought. There are many innovative projects that are helping to build a better world by harnessing frontier technologies for sustainable development (Fig. 1) (Alegre & Matos, 2009). A better understanding of the urban water cycle (water supply, wastewater and stormwater infrastructures) is essential for implementing appropriate urban water policies. This requires considering the energy-water nexus, water scarcity and the development of tools and techniques for integrated water and energy resource management. Within this context, it is important to consider the levels of service and reliability, the risk of service failure and the risk acceptability. The goal is to improve the sustainable use of water and energy while minimizing the carbon footprint and promoting climate change adaptations in a phased way. For instance, the Urban Water Policy framework launched in 2019 by the Ministry of Housing and Urban Affairs (MoHUA) and National Institute of Urban Affairs (NIUA) highlights the need to address multiple supply-side issues such as adequacy and frequency of water supply, affordability and pricing, water quality and institutional sustainability of water utilities. One of the main challenges in the current world is to ensure water quality and availability for all. The environmental assessment of buildings considers energy and waste factors that have an impact on the quality of life of the residents—by applying risk management measures in a rigorous way. Our hypothesis is whether residents who live in new—green buildings that prioritize environmental sustainability as a design principle will report higher levels of life satisfaction than those who live in the “traditional” buildings (without the “progressive technologies”) that may not meet the same environmental standards. To achieve the 2030 Agenda for Sustainable Development (United Nations, 2022), it is essential to grasp the main trends of urbanization that will shape the future. The United Nations recognizes that sustainable urbanization is a key driver of successful development. Bringing wild nature into urban areas has always been a very feasible option for residents. Buildings placed on pilots, land given back to nature, town in the park with lots of green areas represent symbolic meaning of people owning land, vertical gardens. In the present nature is being more and more urbanized and towns are being found to be more natural and more livable. Green roofs and walls are like

Sustainable Water Management and Hybrid Infrastructures

23

Fig. 1 Water challenge (Kaposztasova, 2015)

islands in the middle of city, connecting humans back with nature (Poórová et al., 2016). Key factor of designing a space with distinct character nowadays is creating healthy cities. Integrating nature into urban areas means covering buildings with plants, designing and constructing vegetative roofs, living walls or implementing green policies. The problems associated with urbanization originate in the changes in landscape, the increased volume of runoff, and the quickened way it moves. The changes in the landscape occurred during the transition from rural and open space to urbanized land use (Minnesota Stormwater manual, 2008). The future will require skillful and creative stewardship of our most vital natural resource, as well as innovative approaches as using hybrid infrastructures to keep water infrastructure strong and resilient (AWWA, 2022). Hybridity is also the foundation for generating diverse ecosystem services and deriving wellbeing benefits from them, which could help make both individual elements and complete infrastructure systems directly relevant to urban residents with different needs and interests (Andersson et al., 2022).

2 Methods and Materials 2.1 Sustainable Water Management A sustainable water management system requires a balance among economic, environmental and social factors, as well as intergenerational equity (Fig. 2). Alternative water sources can offer potential benefits, but they also entail various challenges and trade-offs. The design of the site and building should integrate water conservation,

24

D. Káposztásová et al.

Fig. 2 Blue house—blue green world (Kaposztasova, 2015)

energy efficiency, cost reduction and hybridity as a holistic approach. Moreover, the health and sustainability of the system should be evaluated based on the interactions and synergies among its components (Fan et al., 2019; Liu et al., 2007; Xian et al., 2022). Sustainable water management means using water in a way that meets current, ecological, social, and economic needs without compromising the ability to meet those needs in the future. It requires water managers to look beyond jurisdictional boundaries and their immediate supply operations, managing water collaboratively while seeking resilient regional solutions that minimize risks (SWM, 2020). Many countries are adapting and reforming their water management plans towards more sustainable practices, which involve focusing on implementing water systems that are sustainable in line with reducing water stress (WEF, 2022). The challenge is to change the approach to water, landscape, and building in order to understand their mutual interaction and complex interconnectedness. By recognizing the multiplicative functionality of green constructions and realizing their effective and strategically usable potential, in the urban environment, water must be an available and effective resource for climate recovery projects in urban zones by using innovative technologies (vertical gardens, water retention rooftop climate systems, rain gardens, rainwater recycling retention tanks, bio wetlands, etc.…) and other innovative technologies and solutions for water retention systems. The incorporation of objects such as green roofs and facades, wetlands, ponds, etc. can have benefits in the urban environment as the “sponges” mentioned above. Rainwater can also be managed in spatially very limited areas. When designing objects, it is essential that they perform multiple functions, which is especially important in densely populated areas (Fairbrass et al., 2018).

2.2 Hybrid Infrastructures Hybridity in urban areas presents opportunities for additional ways to build resilience and predict new regimes. Functionally various infrastructural elements can offer

Sustainable Water Management and Hybrid Infrastructures

25

diverse attenuation functions, new ways of actively changing infrastructure connectivity, and a broader portfolio. Urban areas need transformative changes to adapt to these challenges. Here comes the question about what new opportunities can hybrid infrastructure bring. With its more diverse components and different internal logics, hybrid infrastructure opens up alternative and additive ways of building resilience. Secondly, hybrid infrastructure points toward greater opportunities for ongoing (re)design at the landscape level, where structure and function can be constantly renegotiated and recombined (Andersson et al., 2022). Hybrid infrastructure is flexible and multi-functional, and it offers tool for regulating redesigning of systems. Ken Yeang claims that green design is the blending of four co-operating infrastructure strands (Fig. 3) into a seamless system (Poórová et al., 2016; Yeang & Spector, 2011). The grey (engineering) infrastructure is urban engineering infrastructure of roads, drains, sewerage, water reticulation, telecommunications, energy and electric power distribution system. These engineering systems should integrate with the green infrastructure and should be designed to be sustainable (Hart, 2011; Poórová et al., 2016). The red (human) infrastructure is the human community. Buildings, houses, hardscapes and regulatory systems like laws, ethics etc. Our lifestyles, economies, and industries, mobility diet and food production all need to become sustainable (Hart, 2011; Poórová et al., 2016). The life cycles of green and grey infrastructure are distinctly different (Fig. 4). The green (eco) infrastructure is an interconnected network of natural area and open spaces that converses natural eco-system values and functions. This ecoinfrastructure is nature’s infrastructure. Any new green infrastructure must also Fig. 3 Four infrastructures (Poórová et al., 2016; Poórová, 2015)

26

D. Káposztásová et al.

Fig. 4 Hybridity in urban infrastructures

enhance the natural functions of what is already there (Hart, 2011; Poórová et al., 2016). The connectivity of the landscape with the built environment is a horizontal and a vertical process. An obvious demonstration of horizontal connectivity is the provision of ecological corridors and links in regional and local planning which are crucial in making urban patterns more biologically viable. Connectivity over impervious surface can be achieved by using eco-bridges, undercrofts and ramps. Besides improved horizontal connectivity, vertical connectivity is also necessary, since most buildings are not single but multi-storey (Blanc, 2012; Poórová et al., 2016). The blue (water) infrastructure means the water cycle should be managed to close to origin, although this is not always possible. Rainwater needs to be harvested and recycled (Sły´s et al., 2012). Surface water needs to be retained within the site and returned to the land for the recharging of groundwater. Water used in the built environment needs to be recovered and reused wherever possible. Combined with green eco-infrastructure, storm water management enables the natural processes to

Sustainable Water Management and Hybrid Infrastructures

27

Fig. 5 Hypothesis—flowchart

infiltrate, evapo-transpire or capture and use storm water on or near site, potentially generating other environmental benefits (Hart, 2011; Kaposztasova, 2015; Poórová et al., 2016). Slovakia faces two major water management challenges. Firstly, it has the highest prevalence of individual sanitation systems in the EU and non-compliance with the Urban Wastewater Treatment Directive, particularly in rural areas and small agglomerations. Secondly, there is a large finance gap and high reliance on EU funding for drinking water, sanitation and flood protection. One central difference is that societal functions of green infrastructure are characterized by regenerative processes, while grey infrastructure to uphold functions need substantial financial investment in continued engineering dealing with material decay. However, the unique contributions or opportunities in combining the two are less explored (Whelchel et al., 2018).

2.3 Aims and Approaches The aim of hybrid infrastructures is to respond to the specific needs of urbanized areas and their inhabitants as a result of extreme weather fluctuations, disproportionate

28

D. Káposztásová et al.

heating of urban agglomerations, increasing production of organic waste, and their inefficient use. In our research we established the main hypothesis: We assume that the quality of life of residents is directly proportional to the quality of the environment of the buildings where they work and the amount of built-in green infrastructures. The goal is to find out how people awareness about sustainable water management and hybrid infrastructures changed during the years in Slovakia. For this purpose, we used the questionnaire. Questionnaire is a set of questions for obtaining statistically useful or personal information from respondents (MerriamWebster, 2017). Preferred type of questions were closed-ended questions, giving a list of predetermined responses (yes/no). Respondents were asked to answer some questions in their own words using open-ended questions (please specific why). This chapter presents some interesting results of 5 questionnaires completed from 2010 to 2023 that focused on rainwater harvesting systems, grey water use risk analysis, respondent’s general overview about the green walls, green wall/roof effect on respondent, ecology/air quality and respondent’s opinion, sustainable water use, water habits and the last one in 2023 was aimed at knowledge of respondents about sustainable water use, sponge city and hybrid infrastructures in urban areas. Each questionnaire was filled in by different number of respondents (from 95 respondents in 2010 to 200 in year 2015…) but for comparison we used 95 respondents answers of each questionnaire, and all respondents were from Slovakia.

2.3.1

Q1—Questionnaire (2010)

The questionnaire was focused on alternative water sources and water use in general. The original study (Karelova, 2010) presented the questionnaire in 3 group of questions. At the beginning of questionnaire there were a couple of basic questions (age, gender, country etc.), then water habits, awareness of water types etc. Second group of questions was focused on practical experiences of rainwater harvesting system (RWH) for example (in a case they were experts—was filled in by 33 respondents from 95): when did you do your first design, what problems did you face during design process, have you seen increased demand for RWH in recent years, what standards or manuals do you use for your designs, etc. The target of the last group of questions was to obtain information about risks in RWH. This part is subjective based on respondent experiences and opinions. At this part respondents assigned values from 1 to 10 (1 for the lowest risk 10 for the highest risk) for the sub-system depending on the significance of the risk (Karelova, 2010). One of the most important facts is that 100% of respondents use drinking water for all household purposes. Of course, this also includes flushing toilets, while only less than half, 46% of the respondents have a double tank, or saving flushing device. 92% of respondents would consider using rainwater if they were building a new house and 57% of respondents would consider installing such a system only if the payback was within 5 years.

Sustainable Water Management and Hybrid Infrastructures

29

The results show that the riskiest parts of the RWH system according to questionnaire are: the pump, the filter, the tank. According to the questionnaire, we can sum up that the greatest attention should be paid to the design, installation and maintenance of these three parts of the system. Approximately half of the respondents think that there is a lack of the information about the RHW system usage of users what rivets our attention to this kind of risk as well.

2.3.2

Q2—Questionnaire (2015)

Questionnaire on Water (Kaposztasova, 2015; Káposztásová & Vranayova, 2018), as one of data collection methods gives a closer look to water habits of households. Therefore, questionnaire has been sent out to the respondents to identify the water habits in their countries and from all over the world. The questionnaire was completed by the group of 200 (95 were form Slovakia) people from different spheres of society divided to 85 male and 115 female respondents. The 75% of them live in the family houses. In Slovakia no grey water use was identified and some of the houses are not connected to main water supply (reasons—good quality of the water in the well, no water supply connection). Important fact is that 80% of respondents use potable water for all domestic purposes such as flushing toilets and watering the garden or washing their cars. Our respondents were asked if they are afraid of grey and rainwater use, in fact Slovaks were more afraid of grey water than rainwater, due to lack of information about such system application in Slovakia (Kaposztasova et al., 2015).

2.3.3

Q3—Questionnaire (2018)

The questionnaire—Q3 (Alhosni, 2018) focused on green structure—green walls: respondent’s general overview about the green walls, green wall effect on respondent, ecology/air quality and respondent’s opinion. The questionnaire was accessible at the Faculty of Civil Engineering, Technical University of Košice between December 11, 2017, and February 09, 2018. 145 respondents responded it. First questions provided basic information about the respondents. Gender and age and focused on respondent’s general overview about the green walls/roofs. The questions are about green walls in Slovakia and in other countries, its financing and maintenance. Set of questions about effects of green wall on respondents proves that 86.2% think that the interior with green wall is more attractive, 84.1% is feeling calmer next to the green wall and 88.3% of respondents do not feel depressed around the green wall. The set of questions about ecology and air quality claims positive information that 80% know about positive effects of green walls. 63.4% think that the green wall has positive impact on their work productivity. 54.5% don’t know if the green wall is increasing the humidity in its environment. 51.7% don’t know if the green wall is increasing air quality in its environment and 64.8% don’t know if the green wall is increasing the dust in its environment, if it is reduced or increased.

30

D. Káposztásová et al.

The original study (Alhosni, 2018) presented that only 20% do not know about the fact that the green walls have different positive benefits like ecological point of view.

2.3.4

Q4—Questionnaire (2018)

The questionnaire—Q4 was dedicated to grey and rainwater use in Slovakia. It started by basic questions as gender and age and focused on respondent’s general overview about grey and rainwater systems. The study was taken by Migelova (2018) and it was focused on the possibilities of purifying grey water on natural bases, particularly through the vegetation walls.

2.3.5

Q5—Questionnaire (2023)

The questionnaire—Q4 is focused on sustainable water management and hybrid infrastructure in urban areas. The goal was to find out respondent’s knowledge of this issue. Firstly, basic questions were set as—country, gender. Second part consisted of 3 questions: Do you understand the concept of sustainable water management? …Do you understand the concept of sponge city? …Do you understand the term of hybrid infrastructure in urban areas, would you prefer it?

3 Results and Discussion The challenge was to find out how during the years from 2010 till 2023 the public awareness of the issue changed. The comparison was made from Q1 to Q5 (Table 1). The limitation of comparison is that some questions were different and there is a need to prepare new questionnaire with the missing ones to complete this study for green structures. Also, comparison between attitudes and ideas of Slovak and foreign respondents will be explored. The majority of Q1 respondents have a positive attitude towards alternative water use (91%) and RWH systems and would agree to install it either at home or at work. Also, most of them think that the use of such systems has a perspective in our conditions, but of course there were also a few skeptics among the respondents who see the disadvantages of the system in its failure rate, maintenance requirements, or price. What we found interesting is that more than 86% of respondents would welcome the unified design guide for our conditions. Q2 respondents in 2015 considered that even they are afraid of reuse of water around 85% Slovaks would think about sustainable solutions if they would build a new house and 55% of respondents would consider installing such system if the return on investment is between to 6–10 years.

Sustainable Water Management and Hybrid Infrastructures

31

Table 1 Data of Q1–Q5 Questionnaire

Year

Respondents

Nationality

Av. age

Focused on

Q1

2010

95

Slovak

41

Alternative water sources and water use in general

Q2

2015

95

Slovak

43

Alternative water sources and water habits

Q3

2018

95

Slovak

28

Green structure—green walls/ facades

Q4

2018

95

Slovak

45

Grey and rainwater sustainable solutions

Q5

2023

95

Slovak

45

Sustainable water management and hybrid infrastructure

Only about 15% of Q3 respondents in 2018 claim to not know green structures, what is positive information. 60% claims to never see a green wall in Slovakia, 46.8% claim to never see a green wall abroad. 51.0% think that building a green wall/roof is a financially demanding affair in terms of input costs. Only 22.7% say that maintenance of green wall/roof is challenging, what is an interesting fact, because maintenance of green structure is challenging. The results of Q4 in 2018 showed that more than 65% of respondents are still concerned about the use of grey water and less (39%) are afraid of rainwater use. More than 60% of respondents think that it is necessary to install alternative water sources in new buildings. The results of Q5 are positive—more than 87% of respondents understand the concept of sustainable water management. Only 53% doesn’t know what sponge city is and the minority know the term of hybrid infrastructures (61% of respondents doesn’t know the exact meaning of hybridity). To sum up the most of Slovak respondents (Q1–Q5) are pro water saving oriented. The awareness of respondents is changing in positive way during the years. We can see that even when in 2010 they would install sustainable solution if the payback was within 5 years in 2015, 2018 it changed to 6–10 years (Fig. 6). In 2010 less than 40% knew about all benefits rising from RWH systems and in 2023 more than 87% of respondents know what sustainable water management is and they understand the concept. In 2018 there were about 60% of them who didn’t see any green wall in Slovakia and now more than 60% know the benefits of green infrastructure. They would like to live in areas created by green and blue infrastructure and they are open to new solutions but there is still some distress of health risks from these systems (Fig. 7). Despite the fact that grey water reuse is already becoming an essential and solution for water supply. Slovakia belongs to countries focusing mainly on fresh water supplies or well water resources. In Slovakia this area hasn’t been so developed yet. It is necessary to define regulation and set standards for designing hybrid systems

32

D. Káposztásová et al.

Fig. 6 Change of payback period acceptable by respondents during 2010–2020

Fig. 7 Trend of raising awareness of respondents during the years 2010–2023 about the sustainable water management solutions

for example according to foreign national standards and performed experiments in Slovak conditions.

4 Conclusions New technologies and better understanding of hybrid systems allow us to reduce our water footprint. People expect to have safe water and sanitation; therefore, when recycling water, it is essential to protect public health and the environment. The classic pattern consists of potable use for all purposes and when it is possible have a well, to use its water for irrigation in Slovakia. It is inevitable to educate our public about the possibilities of the blue green infrastructures and to explain the benefits of hybridity in urban areas. The results from questionnaires show the raising awareness of people in understanding of sustainable water management but there is a need to also present opportunities for hybrid infrastructures. Acknowledgements The authors are grateful for the support of the Slovak Research and Development Agency APVV-18-0360 “Active hybrid infrastructure towards to a sponge city”.

Sustainable Water Management and Hybrid Infrastructures

33

References Alegre, H., & Matos, R. (2009). Paving the way for a sustainable asset management of urban water infrastructures of the 5th World Water Forum. Water Asset Management International, 5(2), 19–20. http://repositorio.lnec.pt:8080/jspui/handle/123456789/17200 Alhosni, M. S. (2018). Multipurpose green walls. Thesis, Technical University of Kosice, Slovakia, 2018. Andersson, E., Grimm, N. B., Lewis, J. A., Redman, CH. L., Brthel, S., Colding, J., & Elmqvist, T. (2022). Urban climate resilience through hybrid infrastructure. Current Opinion in Environmental Sustainability. https://doi.org/10.1016/j.cosust.2022.101158 AWWA—American Water Works Association. (2022). Water 2050. awwa.org/Resources-Tools/ Water-2050. Accessed in November 2022. Blanc, P. (2012). The vertical garden: From nature to the city. W.W. Norton & Company. ISBN 978 0 393 73379 2. Egerer, M., Haase, D., McPhearson, T. et al. (2021). Urban change as an untapped opportunity for climate adaptation. Npj Urban Sustainability, 1, 22. https://doi.org/10.1038/s42949-02100024-y Fairbrass, A. (February 19, 2018). Green infrastructure for London: A review of the evidence. A report by the Engineering Exchange for Just Space and the London Sustainability Exchange. Londons Global University. Fan, Y., Fang, C. H., & Zhang, Q. (2019). Coupling coordinated development between social economy and ecological environment in Chinese provincial capital cities-assessment and policy implications. Journal of Cleaner Production, 229, 289–298. https://doi.org/10.1016/j.jclepro. 2019.05.027 Hart, S. (2011). EcoArchitecture the work of Ken Yeang. Wiley. ISBN: 978 0 470 72140 7. Kaposztasova, D. (2015). Integrated management at the building level. Thesis, Technical University of Kosice, Slovakia, 2015. Káposztásová, D., & Vranayova, Z. (2018). Decision analysis tool for appropriate water source in buildings. In A. Negm, & M. Zeleˇnáková (Eds.), Water resources in Slovakia: Part II. The handbook of environmental chemistry (Vol. 70). Springer. Kaposztasova, D., Rysulova, M., & Purcz, P. (2015). Integrated building water management. WSEAS Transactions on Environment and Development, 11, 282–288. ISSN 2224-3496. Karelova, Z. (2010). Stormwater management in compliance with sustainable design of buildings and environmental conception. Thesis, Technical University of Kosice, Slovakia, 2010. Liu, J., Dietz, T., Carpenter, S. R., Alberti, M., Folke, C., Moran, E., Pell, A. N., Deadman, P., Kratz, T., Lubchenso, J., Ostrom, E., Ouyang, Z., Provencher, W., Redman, CH. L., Schneider, S. H., & Taylor, W. W. (2007). Complexity of coupled human and natural systems. Science, 317(5844), 1513–1516. https://doi.org/10.1126/science.1144004 Merriam-Webster. (2017). Questionnaire. www.merriam-webster.com/dictionary/questionnaire. Accessed on September 2022. Migelova, S. (2018). Green walls as options for grey water treatment. Thesis, Technical University of Kosice, Slovakia, 2018. Minnesota Pollution Agency. (2022). Minnesota Stormwater manual, 2008. https://stormwater.pca. state.mn.us/index.php. Accessed on 18 December 2022. Poórová, Z. (2015). Natural and artificial green design environment and its effect on people living and working in it. Bothalia, 45(2), 23–32. ISSN 0006-8241. Poórová, Z., Tóth, Š., &Vranayová, Z. (2016). Green roof—Integration of artificial and natural environment (p. 60). LAP LAMBERT Academic Publishing. ISBN 978-3-659-84635-9. Sły´s, D., Stec, A., & Zelenakova, M. (2012). A LCC analysis of rainwater management variants. Ecological Chemistry and Engineering S, 19(3), 359–372. https://doi.org/10.2478/v10216-0110026-7 United Nations. (1987). Brundtland report. www.are.admin.ch/are/en/home/media/publications/ sustainable-development/brundtland-report.html. Accessed on October 2022.

34

D. Káposztásová et al.

United Nations. (2022). UN sustainable development goals. un.org. Accessed on July 2022. Water Foundation. (2020). Sustainable water management (SWM) profile. https://waterfdn.org/sus tainable-water-management-swm-profile/. Accessed on December 2022. WEF. (2022). WEF: Ensuring sustainable water management for all by 2030. https://www.wef orum.org/impact/sustainable-watermanagement/ Whelchel, A., Reguero, B. G.,Van Wesenbeeck, B., & Renaud, F. (2018). Advancing disaster risk reduction through the integration of science, design, and policy into eco-engineering and several global resource management processes. https://doi.org/10.1016/j.ijdrr.2018.02.030 Xian, C. F., Fan, Y., Zhang, J., & Zhang, L. (2022). Assessing sustainable water utilization from a holistic view: A case study of Guangdong, China. Sustainable Cities and Society, 76, 103428. https://doi.org/10.1016/j.scs.2021.103428 Yeang, K., & Spector, A. (2011). Green design: From theory to practice. Black Dog Publishing. ISBN 978 1 907317 12 5.

Analysis of Climatic Parameters in Urban Area Adam Repel, Patrik Nagy, Mária Hlinková, Marcela Bindzárová Gergeˇlová, and Martina Zelenáková ˇ

Abstract Rainwater management is currently receiving increased attention. In recent years, the priority has not only been to divert rainwater through sewers to the recipient, predominantly alternative management methods consisting of various methods of soaking or further use of rainwater have come to the fore. With the increasing area of paved areas, there are problems related to the operation of the sewage network, which causes a large amount of rainwater that is drained from the country. All stormwater management systems are designed based on design rain values, which are empirical values obtained on the basis of long-term observations. Intensive, short-term downpours are the most important for draining precipitation waters. The design rain values that are currently used in Slovakia for the design of storm sewer systems come from 1973. Due to the long time and significant demonstrable changes in the climate in Slovakia, it can be expected that the design rain values change over time. The submitted contribution deals with the analysis of currently used design rain parameters and the evaluation of these data on the basis of long-term A. Repel (B) Institute of Technology, Economics and Management in Construction, Faculty of Civil Engineering, Technical University of Kosice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected] P. Nagy · M. Hlinková · M. Zeleˇnáková Institute for Sustainable and Circular Construction, Faculty of Civil Engineering, Technical University of Košice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected] M. Hlinková e-mail: [email protected] M. Zeleˇnáková e-mail: [email protected] M. Bindzárová Gergeˇlová Faculty of Mining, Ecology, Process Control and Geotechnology, Technical University of Košice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected]

© The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 Z. Vranayova et al. (eds.), Sponge City Hybrid Infrastructure, Earth and Environmental Sciences Library, https://doi.org/10.1007/978-3-031-38766-1_3

35

36

A. Repel et al.

measured precipitation totals after 1973. The contribution also analyzes daily and 10-min precipitation totals recorded at several stations within the entire territory of Slovakia. Keywords Precipitation · Rainwater · Storm sewer · Storm management system · Climate change · Trend · Slovakia

1 Introduction When sizing sewers and rainwater management systems, especially in urbanized basins, it is important to analyze precipitation events that have occurred in the past in a given area. In hydrometeorology, more and more attention is paid to the continuous registration of precipitation. Data from the recording of the ombrograph, i.e. a device for measuring precipitation, is used for the dimensioning of sewers, while only those rains that last relatively short and are extremely abundant are considered significant. These are heavy storm rains, downpours and cloudbursts. These short-term rains usually reach great intensity. However, they occur rarely and vary considerably from place to place. In order to obtain knowledge about their area distribution, it is necessary to process a dense network of rain gauge stations. The amount of precipitation that fell on the earth’s surface, its temporal and spatial distribution is determined by measurement. For this, a network of rain gauge stations is used, arranged so that the characteristics of rain in the entire territory are determined as accurately as possible. The rain gauge station itself consists of a rain gauge with accessories. In order to obtain information about the amount of rain, about the duration of rain, its intensity and its time course at a point (that is, a meteorological/precipitation measuring station), ombrographs are used. Ombrogaph is recording the time increase of rain heights, or intensigraphs, recording the time course of intensity. Climate change has been one of the most discussed topics worldwide in recent years (Biˇcárová & Holko, 2013). Many authors, not only in Slovakia, but also abroad, dealt with the impact of climate change in their studies (Afzal et al., 2011; ArnbjergNielsen, 2006; Croitoru et al., 2016; Dziopak & Starzec, 2015; Faško, 2000; Gaál et al., 2008; Gong et al., 2004; Kadlec & Toman, 2002; Keggenhoff et al., 2014; Kohnová et al., 2006). The identified climate changes have an impact on the hydrological cycle, in which they also cause more significant changes. These are mainly changes in the intensity and duration of precipitation, extreme weather fluctuations, widespread melting of snow and glaciers, increased evaporation of water vapor, and also changes in soil moisture conditions and water runoff. Forecasts of the impact of climate change were published for Slovakia, which were presented in a document on the impact of climate change on several areas in the Slovak Republic (Šamaj & Valoviˇc, 1973; Urcikán & Rusnák, 2004). Climate models show changes in the distribution of atmospheric precipitation in Europe and the frequency and intensity of extreme precipitation events. By 2075 the total

Analysis of Climatic Parameters in Urban Area

37

amount of precipitation in Slovakia is expected to decrease by 10%, and the volume of usable water resources will decrease by up to 30–50% in the period 2075–2100. In the future, an uneven precipitation distribution on the Slovak Republic territory is expected. According to several scenarios, a significant decrease in annual runoff is expected, especially in the lowlands. An increase in long-term monthly flows in the basins is also expected in the spring months, on the contrary, a significant decrease is expected in the summer period. Prolonged drought during the summer months will bring water shortages. Long periods of drought will be punctuated by short but very intense rainfall events that will need to be dealt with. According to available studies and models, an increase in the number of downpours is not expected, but the intensity of these precipitations is expected to increase by up to 50%. For this reason, an increase in the number of flash floods is expected. As a result of climate change, the following negative effects in the hydrological regime can be expected in the coming years: • An increase in total runoff from the basin in the cold half of the year (winter months) and a decrease in the amount of water accumulated in the snow cover. • Reduction of soil moisture and reduction of underground runoff during the warm half of the year (summer months). • An increase in surface runoff in the summer months, which can lead to increased soil erosion. • Increasing the number and extending the duration of dry periods. • Loss of usable water resources. The most dangerous and negative impact on urbanized basins is high-intensity short-term precipitation. Several studies have proven an increasing trend in the intensity and periodicity of the occurrence of torrential rains with a short duration. These precipitations are decisive for the design of the rainwater drainage system in urbanized areas. The increase in the amount and intensity of short-term rains was also proven in the analysis of precipitation data for the last 40 years in the territory of South Moravia. The analysis of short rainfall events is also dealt with in a study developed for the conditions of Denmark, in which the data recorded during intense downpours from 41 rain gauge stations were analyzed, where a significant statistical trend of an increase in intense downpours over recent years was proven. A number of studies have been carried out around the world that examined the change in the distribution of precipitation over time, namely the increase in the number of dry days and, at the same time, the more frequent occurrence of heavy downpours. Analysis of data from 28 rain gauge stations in northern Scotland showed that although the upward trend in the amount of precipitation was not continuous, significant trends were observed in the number of dry days and in the maximum annual length of the dry season, which means that the distribution of precipitation during the year is changing. Similar results were presented in a study from China, where a slightly decreasing trend in daily precipitation was observed, but on the other hand, a significant decrease in the number of rainy days and an increase in the number of high-intensity precipitation events were observed. An increase in the number of dry days was also recorded in Romania, where a significantly positive trend

38

A. Repel et al.

in the number of dry days was proven, or in Georgia, where there was an increase in the total amount of precipitation while the number of rainy days decreased. So far, many studies dealing with the statistical analysis of precipitation events, including the number of dry days, have not been carried out in Slovakia. Data on total precipitation in the territory of the Western Carpathians was brought by the analysis of time series of daily precipitation. In Slovakia, a significant increase in days with a daily precipitation total of 40–60 mm was also proven, proving the increase in the number of short-term downpours. Currently, the hydrological regime is being influenced by urbanization and climate change. Climate change brings with it changes in precipitation, which affect the changed landscape due to urbanization. This brings with it a high increase in total water runoff from urbanized basins, and for that reason it is necessary to pay significant attention to this issue. The goal of rainwater management in an urbanized watershed should be mainly to slow down the total water runoff from the watershed and retain as much rainwater as possible directly in the urban environment.

2 Study Area and Input Data 2.1 Study Area The territory of interest is the territory of the whole of Slovakia. In the thesis, precipitation totals from precipitation measuring stations distributed throughout the territory of the Slovak Republic are analyzed. The Slovak Republic is a country located in Central Europe, its total area is 49,035 km2 . The topography of the terrain is very diverse. The lowland terrain in the southeast and southwest of the territory gradually passes to the mountainous areas in the north of the territory. The lowest point of the territory is located on the East Slovak Plain at a height of 94.3 m above sea level, the highest point is Gerlachovský štít in the High Tatras in the north of the territory with a height of 2655 m above sea level. The northern regions are colder and rainier than the southern regions due to their northern location and higher altitudes (Fig. 1). The climate of Slovakia is influenced by the prevailing westerly air flow in moderate latitudes between permanent pressure formations, the Azores pressure high and the Icelandic pressure low. The westerly flow brings moist oceanic air of moderate latitudes from the Atlantic Ocean. The influence of the Atlantic Ocean on Slovakia’s climatic conditions gradually decreases on average from west to east, which is reflected, for example, in the fact that winters in eastern Slovakia at the same altitude are up to 3 °C colder than in the west of the territory. The sunniest area is the southeastern half of the Danube Plain with 2000–2200 h of sunshine per year. The northern and northwestern Slovakia areas have the least sunshine, approximately 1400 to 1500 h per year. Based on long-term measurements, the Danube Lowland is the warmest location, with an average annual temperature of 9 to 11 °C (−1 to −2 °C in winter and 18 to 21 °C in summer). The average annual temperature decreases with

Analysis of Climatic Parameters in Urban Area

39

Fig. 1 The position of Slovakia within Europe and the topography of Slovakia’s territory

altitude. At an altitude of 1000 m above sea level the average annual temperature is 4 to 5 °C, on the ridges of the High Tatras the average annual temperature is less than 3 °C. The absolute maximum temperature measured in Slovakia was 40.3 °C at the station in Hurbanovo, and the absolute minimum temperature −41 °C was measured at the Vígˇlaš-Pstruša station. The long-term average annual precipitation in Slovakia varies from approximately 500 mm in the southern part of western Slovakia to more than 2000 mm in the High Tatras. Relatively low rainfall totals are in the so-called the rain shadow of the mountains. For this reason, the Spiš basins are relatively dry, protected from the southwest to the northwest by the High and Low Tatras and from the south by the Slovak Rudohor. On average, less than 600 mm of precipitation falls here in a year. Slovakia’s precipitation generally increases with altitude by approximately 50–60 mm per 100 m of height. The mountains in the north-west and north of Slovakia are generally richer in atmospheric precipitation than those in Slovakia’s central, southern and eastern regions. During the year, approximately 40% of the precipitation falls in the summer period (June–August), 25% in the spring, 20% in the autumn and 15% in the winter (the predominance of precipitation in the summer is therefore clear). The rainiest month is usually June or July, with the lowest rainfall from January to March. The high variability of precipitation causes frequent and sometimes long-lasting dry periods, especially in the lowlands. The highest daily rainfall total was measured in Salka na Ipli in 1957 (231.9 mm). During the summer, barges with high precipitation totals are often found throughout the territory.

40

A. Repel et al.

Fig. 2 Location of rain gauge stations with daily rainfall totals within Slovakia

2.2 Input Data The work deals with the analysis and evaluation of the measured precipitation totals in Slovakia in the long term. Daily precipitation totals (mm/day) and short-term precipitation totals in 10-min intervals (mm/10 min) are used in the work. All input data were provided by the Slovak Hydrometeorological Institute (SHMÚ) for research and processing this chapter.

2.2.1

Daily Precipitation Totals

For the purpose of long-term evaluation of daily, monthly and annual rainfall totals, daily rainfall totals from 48 climate stations in Slovakia were used (Fig. 2). These are 12 stations in the western part of Slovakia, 17 in central Slovakia and 19 in the eastern part of Slovakia. The location of individual stations within the territory of Slovakia is shown in the picture and the list of all stations is shown in the Table 1. Daily precipitation totals from all stations form complete time series, without missing data. The observation period is from 39 to 119 years (the longest period, station Hurbanovo). All data were obtained from the Slovak Hydrometeorological Institute.

2.2.2

10-Min Precipitation Totals

For the design of rainwater management systems, the most important are the intensities of short-term rains that occur during downpours and cannot be sufficiently

Analysis of Climatic Parameters in Urban Area

41

Fig. 3 Location of rain gauge stations with 10-min rainfall totals within Slovakia

identified on the basis of daily rainfall totals. For that reason, short-term rainfall events were also analyzed, which were obtained from automatic rain gauge stations recording rainfall totals in 10-min intervals. The data set of 10-min totals was not as extensive as the data set of daily rainfall totals and consisted of 10-min rainfall totals from 9 rain gauge stations, which were evenly distributed throughout Slovakia. The list of rain gauge stations with 10-min rainfall totals is shown in Table 2 and their position is drawn in Fig. 3.

3 Results and Discussion 3.1 Analysis of Daily Rainfall The analysis of precipitation totals in this paper consists of a trend analysis of the number of days without precipitation in each year of the observed period, a trend analysis of the total annual total for each year of the observed period, and also a trend analysis of the maximum daily totals for each year. The Mann Kendall trend test method was used for trend analysis. The results of the trend analysis were evaluated at a significance level of 5%. The trend analysis results are shown in Table 1 on the next page. The table consists of the station’s name, the period of observation for each station, including the total number of years, the average annual rainfall for each station, and then the evaluation of the trend analysis for all three observed parameters. Rain gauge stations are divided in the table into stations in western, central and eastern Slovakia. The stations are listed alphabetically for individual regions of Slovakia. The trend analysis results are represented by the symbols 0, P and N, where 0 represents no confirmed trend, P represents a positive (increasing) trend in the time

42

A. Repel et al.

Table 1 List of stations with daily rainfall totals, observed periods and locations

Bratislava-Koliba

Observed period

Number of years

Height above sea level (m n.m.)

Latitude

Longitude

1950–2019

69

287

48°10 7

17°6 38 17°4 13

Bratislava-letisko

1951–2019

68

182

48°9 8

Dudince

1977–2019

42

139

48°10 9

18°52 34

115

47°52 23

18°11 39

58

176

48°29 12

17°40 15

58

124

48°12 0

17°16 29

586

48°15 21

17°9 14 17°49 58

Hurbanovo

1900–2019

Jaslovské Bohunice 1961–2019 Kráˇlová pri Senci 1961–2019

119

Malý Javorník Piešˇtany

1982–2019

37

1951–2019

68

163

48°36 47

Podhájska

1961–2019

58

145

48°6 27

18°20 21

260

48°46 11

18°35 38 17°59 26

Prievidza Veˇlké Ripˇnany

1973–2019

46

1966–2019

53

188

48°30 38

Žihárec

1961–2019

58

111

48°4 13

17°52 55

575

48°26 58

18°55 18 19°44 11

Banská Štiavnica Boˇlkovce

1970–2019 1951–2019

68

214

48°20 20

Bzovík

1978–2019

41

355

48°19 9

19°5 38

228

48°12 24

19°19 12 18°36 51

Dolné Plachtince

1965–2019

49

54

Dolný Hriˇcov

1976–2019

43

309

49°13 56

Chopok

1955–2019

64

2005

48°56 38

19°35 32

640

49°2 21

19°43 31 19°39 57

Liptovský Hrádok

1950–2019

69

Lom nad Rimavicou

1980–2019

39

1018

48°39 38

Oravská Lesná

1951–2019

68

780

49°22 6

19°10 59

Ratková

1968–2019

51

311

48°35 34

20°5 37

215

48°22 26

20°0 38 19°8 31

Rimavská Sobota

1951–2019

68

Sliaˇc

1951–2019

68

313

48°38 33

Štrbské Pleso

1951–2019

68

1322

49°7 10

20°3 48

901

48°50 55

20°11 21 19°19 19

Telgárt Vígˇlaš - Pstruša

1951–2019

68

1972–2019

47

368

48°32 39

Žiar nad Hronom

1984–2019

35

275

48°35 10

18°51 8

365

49°12 19

18°44 48 20°25 27

Žilina ˇ Cervený Kláštor

1981–2019

38

1961–2019

58

469

49°23 14

Jakubovany

1973–2019

46

410

49°6 32

21°8 27 22°0 22 21°13 21

Kamenica nad Cirochou

1951–2019

68

176

48°56 20

Košice-letisko

1951–2019

68

230

48°40 20

(continued)

Analysis of Climatic Parameters in Urban Area

43

Table 1 (continued)

Lomnický štít

Observed period

Number of years

Height above sea level (m n.m.)

Latitude

Longitude

1951–2019

68

2635

49°11 43

20°12 54 21°54 50

Medzilaborce

1961–2019

58

305

49°15 12

Michalovce

1968–2019

51

110

48°44 24

21°56 43

105

48°39 47

21°43 26 22°13 31

Milhostov

1961–2019

58

Orechová

1978–2019

41

122

48°42 19

Plaveˇc

1961–2019

58

485

49°15 35

20°50 45

573

49°15 20

20°31 58 20°14 44 ara>

Podolínec

1982–2019

37

Poprad

1951–2019

68

694

49°4 8

Prešov

1985–2019

34

307

49°1 55

21°18 31

520

48°33 17

20°31 15 20°14 9

Silica

1974–2019

45

Skalnaté pleso

1961–2019

58

1778

49°11 22

Somotor

1961–2019

58

100

48°25 17

21°49 6

380

48°56 35

20°48 8 20°8 37 21°39 0

Spišské Vlachy

1965–2019

54

Tatranská Javorina

1970–2019

49

1013

49°15 47

Tisinec

1963–2019

56

216

49°12 56

Table 2 List of rain gauge stations with 10-min rainfall totals, observation period and maximum total recorded for the entire observed period Station

Height above sea level Observed period Maximum total (10 min) for the observed period

Bratislava - koliba

280 m n.m

2000–2019

16.6 mm

Hurbanovo

112 m n.m

2000–2019

25.3 mm

Kamenica nad Cirochou 184 m n.m

2001–2018

27.1 mm

Košice

206 m n.m

2002–2018

16.1 mm

Liesek

631 m n.m

2001–2020

21.0 mm

Nitra

167 m n.m

2001–2019

17.6 mm

Poprad

685 m n.m

2000–2018

17.9 mm

Sliaˇc

329 m n.m

2000–2019

20.0 mm

Telgárt

886 m n.m

2000–2019

16.9 mm

series, and N represents a negative (decreasing) trend in the time series. The results are also shown in color in the Table 3 for better clarity. There is no observed trend at most rain gauge stations. Decreasing trends occur only in the number of days without rain, increasing trends in the total annual total and maximum daily totals were observed in several stations.

44

A. Repel et al.

Table 3 Results of trend analysis List of station WEST SLOVAKIA Bratislava-koliba Bratislava-letisko Dudince Hurbanovo Jaslovské Bohunice Kráľová pri Senci Malý Javorník Piešťany Podhájska Prievidza Veľké Ripňany Žihárec CENTRAL SLOVAKIA Banská Štiavnica Boľkovce Bzovík Dolné Plachtince Dolný Hričov Chopok Liptovský Hrádok Lom nad Rimavicou Oravská Lesná Ratková Rimavská Sobota Sliač Štrbské Pleso Telgárt Vígľaš – Pstruša Žiar nad Hronom Žilina EAST SLOVAKIA Červený Kláštor Jakubovany Kamenica nad Cirochou Košice – letisko Lomnický štít Medzilaborce Michalovce Milhostov Orechová Plaveč Podolínec Poprad Prešov Silica Skalnaté pleso Somotor Spišské Vlachy Tatranská Javorina Tisinec

Observed period

Number Average of years annual total

Number of days Annual without rain total

Max. daily total

1950–2019 1951–2019 1977–2019 1900–2019 1961–2019 1961–2019 1982–2019 1951–2019 1961–2019 1973–2019 1966–2019 1961–2019

69 68 42 119 58 58 37 68 58 46 53 58

673.3 mm 572.7 mm 592.5 mm 565.7 mm 555.7 mm 522.7 mm 768.9 mm 577.5 mm 557.9 mm 655.5 mm 553.1 mm 573.8 mm

0 P 0 P 0 N 0 0 0 0 N P

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 P 0 0 0 0 0 0 0

1970–2019 1951–2019 1978–2019 1965–2019 1976–2019 1955–2019 1950–2019 1980–2019 1951–2019 1968–2019 1951–2019 1951–2019 1951–2019 1951–2019 1972–2019 1984–2019 1981–2019

49 68 41 54 43 64 69 39 68 51 68 68 68 68 47 35 38

752.0 mm 596.1 mm 615.2 mm 615.8 mm 737.2 mm 1134.0 mm 688.3 mm 883.9 mm 1125.7 mm 725.2 mm 620.2 mm 698.0 mm 1011.9 mm 860.1 mm 621.0 mm 658.6 mm 761.5 mm

N 0 N N 0 N N P 0 0 N 0 0 0 N 0 0

0 0 P 0 0 0 P P P 0 0 0 P 0 0 0 0

P 0 0 0 0 0 0 P P 0 0 0 0 0 0 0 0

1961–2019 1973–2019 1951–2019 1951–2019 1951–2019 1961–2019 1968–2019 1961–2019 1978–2019 1961–2019 1982–2019 1951–2019 1985–2019 1974–2019 1961–2019 1961–2019 1965–2019 1970–2019 1963–2019

58 46 68 68 68 58 51 58 41 58 37 68 34 45 58 58 54 49 56

803.7 mm 637.7 mm 724.1 mm 615.8 mm 1574.2 mm 846.6 mm 635.4 mm 560.8 mm 692.3 mm 709.0 mm 724.1 mm 602.8 mm 648.4 mm 709.6 mm 1374.8 mm 557.7 mm 620.0 mm 1336.1 mm 679.1 mm

N 0 0 0 N 0 0 0 P N 0 0 0 N 0 N N N 0

P 0 0 0 P 0 0 0 0 P 0 P 0 0 P 0 P P 0

P 0 P 0 P 0 0 0 0 0 0 0 0 0 0 0 0 P 0

The above results show a significant difference in annual precipitation totals between western Slovakia and other parts of the country. The average annual rainfall from all stations in western Slovakia is 597.44 mm, in central Slovakia it is 770.86 mm and in eastern Slovakia it is 792.22 mm. The annual precipitation total in eastern and central Slovakia is significantly increased, especially by mountain areas. Among the rainiest areas are the High Tatras (stations Lomnický štít, Tatranská Javorina, Skalnaté pleso) but also the region of northeastern Slovakia (Oravská Lesná).

Analysis of Climatic Parameters in Urban Area

45

The lowest rainfall totals are observed in the south-west of Slovakia (Kráˇlová pri Senci, Podhájska) and in the extreme south-east of Slovakia (Somotor). The differences between the rainiest and least rainy areas are significant, the difference in the average annual total is more than double. The results of the trend analysis are different depending on the specific rain gauge station but also on the observed quantity. In the case of the number of days without rain, a positive trend was demonstrated at 10.4% of the observed stations, a negative trend at 33.3% of the observed stations, and no trend was demonstrated at 56.3% of the observed stations. It is clear from the above that the number of days without rain does not change in more than half of the observed stations. A negative, i.e. decreasing, trend in the number of days without rain was observed at a third of the observed stations. In these stations, there is a decrease in days without rain and an increase in rainy days. This parameter must also be compared with the annual precipitation total. In rain gauge stations, where there is no trend in the overall annual total, but at the same time the number of days without rain is decreasing, it is possible to state that precipitation events are distributed more evenly than in the past, and therefore there are no such extreme rains as in the past. The long-term annual total does not decrease in any of the observed rain gauge stations, no trend in the annual totals was shown in 75.0% of the observed stations, and a negative trend was shown in 25.0% of the observed stations. In western Slovakia, no increase in annual totals was demonstrated, in central and eastern Slovakia, an increasing trend in average annual totals was demonstrated at several stations. The increasing trend of maximum daily totals was shown only at a few stations in Slovakia, 16.7% of the observed stations. No trend in maximum daily totals observed for each year was demonstrated in the remaining stations. The graph in Fig. 4 shows the trend of maximum daily totals for the observed period at all stations in eastern Slovakia. It is clear from the above graph that extreme events with a high daily total occurred in the past as well as today. For each rain gauge station, the three most extreme rainfall events that were measured at the station during the observed period were also evaluated. The goal was to find out whether there is currently an increase in extreme weather events, and thus an increase in the frequency of days with high daily precipitation totals. It is clear from the results of this analysis that extreme precipitation events do not occur only in recent years, they were represented in the past as well. The maximum daily total from all stations for the entire observation period was recorded in 1970 at the Oravská Lesná station, where the total rainfall for the whole day reached a value of 163.2 mm. The second and third highest daily totals were achieved in 1970 and 2008, respectively, in the stations Skalnaté Pleso and Tatranská Javorina. All the mentioned stations are stations located in a mountainous environment. The occurrence of extreme rainy events in the past is also documented by data from the Hurbanovo station, where the highest total for the entire observation period was recorded in 2015 (90.2 mm) and the second highest total was recorded in 1918 (88.8 mm). The same results are also observed in the other stations, where the maximum totals also occur in the entire range of the observed period. Thus, it is

46

A. Repel et al. 160 140

Max daily total (mm)

120 100 80 60 40 20 0

Observed period (1950-2019)

Fig. 4 Course of maximum daily totals for the observed period in the stations of eastern Slovakia

impossible to state an increase in the frequency and intensity of extreme precipitation events. On the graph in Fig. 4 shows the course of maximum daily totals for the observed period in all stations of eastern Slovakia.

3.2 Analysis If 10-Min Rainfall In the first step, the number of downpours (intense rain events) in individual months was determined for each rain gauge station. For the purposes of this assessment, a downpour was defined as any rainfall event in which the 10-min rainfall total reached at least the intensity value given by Šamaj and Valoviˇc (Šamaj & Valoviˇc, 1973) for periodicity p = 5 and rain duration t = 10 min (the lowest value of the design rain intensity given by Šamaj/by Valoviˇc (Šamaj & Valoviˇc, 1973) for t = 10 min). In Fig. 5 shows the distribution of heavy downpours (sum for all stations) within the year. It is clear from the above that heavy downpours do not occur at all in the winter months, on the contrary, the maximum number of downpours occurs in the summer months of June, July and August, as they occur almost exclusively during storm activity, with July being the dominant month. In Table 2 are colored years in which there was a precipitation event in which the design intensity for rain with a duration of 10 min and a periodicity of 0.2 was exceeded. Subsequently, the Table 4 also shows the total observation time at individual stations, and the last column of the table calculates the occurrence of such a precipitation event at individual stations (1 time in n years, where n is given in the table). Considering the periodicity of p = 0.2, a precipitation event should occur 1 time in 5 years. From the results presented in the table, it is clear that, with the exception of the Poprad station, this occurrence was not exceeded. The

Analysis of Climatic Parameters in Urban Area

47

Table 4 Number of precipitation events in which the intensity value according to Šamaj/Valoviˇc (Šamaj & Valoviˇc, 1973) was exceeded (p = 0.2, t = 10 min) for individual stations in individual years

Fig. 5 Number of heavy downpours (in all observed stations) in individual months

highest occurrence of exceeding the design intensity is in the Poprad station (1 time in 4.75 years), the smallest occurrence, on the contrary, in the Telgárt station (only 1 time in 20 years). In the same way, the exceedances of the given intensities are listed in Table 5 (periodicity p = 0.5) and Table 6 (periodicity p = 1.0). It is clear from the results that the design rain intensities given by Šamaj and Valoviˇc (1973) are generally not exceeded more often than their periodicity indicates. Exceeding the occurrence of 1 time in 2 years with periodicity p = 0.5 occurred only in Hurbanovo and Poprad stations, with periodicity p = 1.0 (occurrence 1 time in 1 year) only in Hurbanovo station. In principle, the conclusion can be expressed that, with the exception of the Hurbanovo station, the design rain intensities according to Šamaj and Valoviˇc (1973) are correct and do not exceed them. In the last part of the contribution, constructed IDF curves are presented, which express the dependence of the amount of rain (mm) on the duration of the rain

48

A. Repel et al.

Table 5 Number of precipitation events in which the intensity value according to Šamaj/Valoviˇc (Šamaj & Valoviˇc, 1973) was exceeded (p = 0.5, t = 10 min) for individual stations in individual years

Table 6 Number of precipitation events in which the intensity value according to Šamaj/Valoviˇc was exceeded (p = 1.0, t = 10 min) for individual stations in individual years

(min). In Fig. 6 shows IDF curves for individual stations for periodicity p = 0.2 (occurrence 1 time in 5 years). The graphs compare the IDF curves from the data of design intensities according to Šamaj and Valoviˇc and subsequently the IDF curves constructed from the measured totals during the observed period using the statistical methods Gumbel distribution and Log-normal distribution. From the graphs shown in Fig. 3, it is clear that the IDF curves constructed from the actually measured totals after 2000 have a very similar course to the IDF curves constructed from the design intensities determined by Šamaj and Valoviˇc (Šamaj & Valoviˇc, 1973). Exceeding the design rain intensities can be observed at the Hurbanovo station, very slightly at the Poprad station, and with longer periods of rain also at the Bratislava station. In the other stations, the design rain values are currently lower than the values of 1973. It is also clear from the results that

Analysis of Climatic Parameters in Urban Area

Fig. 6 IDF curves from measured data for individual stations for periodicity p = 0.2

49

50

A. Repel et al.

the Gumbel distribution method produced almost identical results to the log-normal distribution method, which means that either of these two methods can be used.

4 Conclusions The submitted contribution presents partial results from research aimed at evaluating short-term precipitation totals in the territory of the Slovak Republic. From a longterm perspective, the contribution evaluates daily rainfall totals and 10-min rainfall totals in several rain gauge stations in Slovakia. Short-term totals and their design parameters are the basic input data in the design of storm sewers and stormwater management systems. Currently, the design rain parameters from 1973 are used in the design of such systems. This contribution focuses on evaluating these totals and their comparison with the measured rainfall totals in Slovakia after 2000. In the first part of the post, parameters are analyzed based on daily precipitation totals. It is mainly a trend analysis of factors such as the average annual payment, the maximum daily total or the number of days without rain in a year. It is clear from the results that there have been no fundamental changes in these parameters in recent years that would have an impact on water management in the country. Subsequently, the distribution of the occurrence of short-term rains with high intensity within the year is shown. The greatest occurrence of such rains is in the summer months, while such rains do not occur in the winter months, as they are tied to storm activity. In the next part, the contribution focuses on the evaluation of currently used in practice design rain intensities from 1973 and their comparison with rainfall totals recorded at several stations in Slovakia after 2000. It is clear from the results that the intensities used are basically correct and reflect the real occurrence of shortterm downpours and their intensity. Due to the fact that short-term downpours are extremely unpredictable and their occurrence depends on several factors, it cannot be said with certainty that the intensities for individual periodicities will not really be exceeded. However, it is clear from the results that this does not happen to a large extent yet and the values of design rain intensities can be used in practice. Considering the relatively simple procedure by which the design rain intensities are determined from the measured data, it would be desirable to update the design rain intensities annually based on the actual measured precipitation totals. In order to simplify the design process within the territory of the Slovak Republic, it is also worth considering to determine one value of the design rain intensity, which would be valid for the whole of Slovakia. Such a proposal requires further evaluation and statistical analysis, but would significantly simplify the design procedures for storm sewers and stormwater management systems. Acknowledgements This work was supported by the Slovak Research and Development Agency under the Contract no. APVV-20-0281, and a project funded by the Ministry of Education of the Slovak Republic VEGA1/0308/20 “Mitigation of hydrological hazards, floods, and droughts by exploring extreme hydroclimatic phenomena in river basins”.

Analysis of Climatic Parameters in Urban Area

51

References Arnbjerg-Nielsen, K. (2006). Significant climate change of extreme rainfall in Denmark. Water Science and Technology, 54(6–7), 1–8. Afzal, M., Mansell, M. G., & Gagnon, A. S. (2011). Trends and variability in daily precipitation in Scotland. Procedia Environmental Sciences, 6, 15–26. Biˇcárová, S., & Holko, L. (2013). Changes of characteristics of daily precipitation and runoff in the High Tatra Mountains, Slovakia over the last fifty years. Contributions to Geophysics and Geodesy, 43(2), 157–177. Croitoru, A. E., Piticar, A., & Burada, D. C. (2016). Changes in precipitation extremes in Romania. Quaternary International, 415, 325–335. Dziopak, J., & Starzec, M. (2015). Sewage systems—Basics and design. Oficyna Wydawnicza Politechniki Rzeszowskiej, Rzeszow. ISBN 978-83-7934-032-3. Faško, P. (2000). Maximum daily sums of precipitation in Slovakia in the second half of the 20th century. Prace Geograficzne-Zeszyt, 108, 131–138. Gaál, L., Kyselý, J., & Szolgay, J. (2008). Region-of-influence approach to a frequency analysis of heavy precipitation in Slovakia. Hydrology and Earth System Sciences, 12(3), 825–839. Gong, D. Y., Shi, P. J., & Wang, J. A. (2004). Daily precipitation changes in the semi-arid region over northern China. Journal of Arid Environments, 59(4), 771–784. Kadlec, M., & Toman, F. (2002). Posouzení historických srážkových rˇad z hlediska výskytu eroznˇe nebezpeˇcných deštˇu˚ v oblasti jižní Moravy (pp. 35–44). Soil and Water. Scientific Studies RISWC Praha. Keggenhoff, I., et al. (2014). Trends in daily temperature and precipitation extremes over Georgia, 1971–2010. Weather and Climate Extremes, 4, 75–85. Kohnová, S., et al. (2006). Analýza maximálnych úhrnov zrážok v povodí horného Hrona. Slovak Technical University. ˇ na Slovensku. Slov. ped. nakl. Šamaj, F., & Valoviˇc, Š. (1973). Intenzity krátkodobých daždov Urcikán, P., & Rusnák, D. (2004). Stokovanie a cˇ istenie odpadových vôd: Stokovanie I. Navrhovanie stokových sietí. Slovenská technická univerzita.

Measuring Selected Physical Parameters of Hybrid Infrastructure ˇ Marián Vertal , Katarína Lavková Cakyová , and Alena Vargová

Abstract The chapter describes an experimental case study of transforming a part of an industrial area in Košice by applying sponge architecture features. The area’s transformation was divided into 8 phases within which independent experimental constructions were created while implementing extensive green roofs, shelters as well as a wetland roof. Sensors built in the selected layers of the experimental constructions enable long-term monitoring of characteristic values within building constructions exposed to the city of Košice’s climatic conditions. Two-year-long measurements showed a positive impact of sponge construction application on the analyzed roofs. During the monitoring period, the vegetation applied on each of the designed constructions was able to prosper without external irrigation. The reduction of temperatures measured in various construction layers decreases the energy demand for cooling during hot weather periods while thermal protection reduces the energy consumption necessary for heating when the weather is cold. On the whole sponge structure application has proven to decrease the CO2 emissions of the analyzed office building. Both, the roof membrane surface temperature oscillation reduction, and the protection of roof layers from UV radiation, wind, and freezing temperatures reduce the risk of roof defects while prolonging its life. The application of greenery including the roof terrace with wetland not only improved the area’s biodiversity but also created a fire-resistant layer and finally gave the studied area a huge added value. Enriching the facility with the above-mentioned green elements contributed to better social interaction among the building’s staff while also making the space more creative for the researchers.

ˇ M. Vertal (B) · K. Lavková Cakyová · A. Vargová Institute of Architectural Engineering, Faculty of Civil Engineering, Technical University of Košice, Vysokoškolská 4, 042 00 Košice, Slovakia e-mail: [email protected] ˇ K. Lavková Cakyová e-mail: [email protected] A. Vargová e-mail: [email protected] © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 Z. Vranayova et al. (eds.), Sponge City Hybrid Infrastructure, Earth and Environmental Sciences Library, https://doi.org/10.1007/978-3-031-38766-1_4

53

54

M. Vertal et al.

Keywords Green roof · Wetland roof · Industrial zone · CO2 emissions · Temperature decreasing · Experimental roof

1 Introduction Cities play an important role in the development of society, but in recent years, cities and urban areas around the world have faced several problems (Niemets et al., 2021). Especially in connection with climate change, when the risk of heat waves, heat islands effect, increased dustiness, worsening air quality, excessive noise, but also the risk of alternating droughts and floods increases (Karlsson et al., 2016). The traditional solution for rainwater management in cities is the creation of rainwater sewerage for the drainage of this water or the expansion of the network of existing sewerage and the increase in the dimensions of the pipes for the rapid drainage of extreme stormwater (Stovin et al., 2012). However, such solutions require larger investments and often complicated construction in the already existing urban built-up area. On the other hand, cities and urban areas face pressure and the need to expand due to rapid urbanization. This creates pressure not only to create space for living and housing, but also to expand spaces for urban functional zones such as spaces for services, work, infrastructure, and industry (Liu et al., 2022). These zones are often unaesthetic and create the so-called grey areas of the city with specific needs. Especially in the case of industrial zones, these are requirements for functionality and the use of resistant and durable materials such as concrete and asphalt with a minimum of high and low vegetation. This fact significantly contributes to the deepening of problems related to the manifestations of climate change. The lack of space in cities, and the requirement of greening, brought thought and the possibility of using existing constructions with the replacement of layers by vegetation layers that will create a water retention structure as one of the prerequisites for a sponge city (Chan et al., 2018). Vegetated roofs and facades are often used (Cakyova et al., 2021). The indisputable benefit of such constructions is their possible application in already existing buildings and use in highly urbanized areas. Such constructions, which are part of nature-based solutions, can potentially increase cities’ resilience in the context of climate change (European Commission, 2021). There is an assumption that vegetated roofs and facades in cities can reduce the number of heat waves, air pollution, runoff of rainwater and improve rainwater management, but also contribute to greater biodiversity in cities and thereby create ecosystems in cities (Almeida et al., 2021; Chen, 2022; Motlagh et al., 2021; Pumo et al., 2023). The effect of vegetation construction is strongly conditioned by climatic conditions but also by surrounding buildings (Vertaˇl et al., 2018). Although the term vegetation or green roof is relatively well-known in the world, there are only a few studies that would pay attention to the research of vegetation constructions in the

Measuring Selected Physical Parameters of Hybrid Infrastructure

55

climatic conditions of Central Europe (Jamei et al., 2021; Poórová & Vranayová, 2019), respectively in a specific area such as an industrial zone. The trend of rapid urbanization, which can be observed in the case of large cities, is also copied by cities in Slovakia, where it is possible to see that urban functional zones (industrial zones) form a non-negligible part of the city. This effect can also be observed in the city of Kosice (Fig. 1). Although the application of green roofs is mainly encountered in the case of city centers and residential areas (Liu et al., 2021), the application in a functional zone will create an interesting connection between industry and nature. The concept of transformation considers the creation of several types of vegetation structures at the local level of the city of Kosice, but it is assumed that their successful application will create a model for expansion to other parts of Slovakia and the countries of Central Europe. Although industrial zones are a part of every city, they are mostly unaesthetic spaces with a single function. Well-designed industrial zones regarding sustainability, aesthetics and inclusion are rare in Slovakia. The uniqueness of this concept lies in the involvement of the owner (private sector) and the university in the creation and selection of nature-based solutions for a specific industrial zone in the city of Košice. Therefore, it was necessary to consider both partners’ demands and requirements. Realized and proposed constructions with a vegetation layer created in situ laboratories to monitor, record, and analyze selected parameters and phenomena.

Fig. 1 Marking of industrial zones in the city of Kosice (red colour) and examples of their visual value

56

M. Vertal et al.

2 Methods and Materials 2.1 Study Area The area of interest is located in the industrial zone in the suburbs of Košice called Nad Jazerom, with an area of 3926 m2 . The campus has an administrative building, a parking lot with 39 parking spaces, two storage halls, a fire tank and three storage sheds. The administrative building has four floors, no basement, with a flat roof and 4 terraces. The supporting system is a prefabricated skeleton with a filigree ceiling. The building envelope is made of Porotherm 20 masonry and insulated with EPS Baumit openTherm thermal insulation of 140 and 180 mm thick. The roof and terraces are made as single-layer roof structures with an inverted layer order. The gradient layer is made of foam concrete, the waterproofing is made of two layers of asphalt strips, and the thermal insulation is made of extruded polystyrene Roofmate 160 mm thick. The area is mostly built up, whereas space is needed for handling and storage of materials. The vegetation part represents only 14%. Rainwater is drained from the building and paved areas into the public sewerage system. 23% of rainwater is captured on the property thanks to vegetation. The project aims to return vegetation into industrial zones through structures with vegetation layers. The added vegetation should bring several benefits such as increasing water storage, diminishing rainwater runoff into public sewers, cooling the surroundings and constructions, encouraging biodiversity, abating noise and capturing dirt. Furthermore, the denser the vegetation, the more attractive a place is. At the same time, the proposed structures could represent a space for possible research on the behaviour of green roofs and walls in our climate from various points of view (Fig. 2).

Fig. 2 Visualization of the original (left) and proposed (right) area of interest

Measuring Selected Physical Parameters of Hybrid Infrastructure

57

2.2 Zone Transformation The proposal was divided into individual phases, which are gradually implemented (Fig. 3): • • • • • • • •

Phase 1—Experimental roof with biodiversity potential Phase 2—Shelter with three different compositions of green roof Phase 3—Carport with green roof Phase 4—Extension on the west terrace on the 2nd floor Phase 5—Green roof on the 4th north terraces Phase 6—Green wall on the east and south sides of the building Phase 7—Biosolar roof Phase 8—Intensive green roof—2nd north terraces—park on the terrace

The green area would increase from 14 to 41% in the entire area, after applying all phases.

2.2.1

Phase 1—Experimental Roof with Biodiversity Potential 2020–2022

The southern terrace on the 2nd floor is used for research purposes. In 2019, preimplementation works have started for the creation of an experimental roof with biodiversity potential in Košice. The idea of the research was to compare the hydrothermal response of extensive roofs with different substrate thicknesses and a reference roof. In the months of February–April 2020, the pre-implementation phase

Fig. 3 View of the roof constructions of the area of interest with a division into phases: the completed phases are represented by the solid line and the planned phases by the dashed line

58

M. Vertal et al.

took place, where it was necessary to choose the research location, the experiment’s layout design, the design and selection of composition materials, the selection, and the deployment of the measuring infrastructure. From a thermal-technical point of view, it was necessary to modify the terrace before the experimental part of the terrace was created. The original waterproofing of the roof sheathing became the vapour barrier. In order to achieve the required standard requirements, it was necessary to add thermal insulation PIR board with a thickness of 60 mm. The added waterproofing layer was designed based on PVC foil. The floor plane of the terrace and the composition of individual test segments with layer thicknesses are shown in Fig. 4. Table 1 describes the water storage properties of the drainage and substrate layer used on the southern terrace. The terrace area is divided into 3 experimental segments: • Extensive green roof with a 120 mm-thick substrate layer (TS I.) • Reference layer with a gravel layer (TS II.) • Extensive green roof with 240 mm-thick substrate layer (TS III.) The same types of vegetation were used for both segments of the green roof, the most often were used Sedum album ‘Coral Carpet’, Sedum spurium ‘Roseum’, Sedum album ‘Murale’, Sedum rupestre ‘Angelina’, Hieracium maculatum, Dianthus deltoides and others.

Fig. 4 Floor plane of southern terrace and composition of roofs

Measuring Selected Physical Parameters of Hybrid Infrastructure Table 1 Properties of used green roof materials—Phase 1 (green area 35.2 m2 )

59

Drainage and storage panel Bauder RE 40 Material

HDPE

Height of element

40 mm

Water storage

Approx. 13.5 l/m2

Vegetation substrate Bauder LBB-E Thickness

120 mm

Main mineral element

Lava, slate, pumice

Water storage

40% volume

Vegetation substrate Bauder LBB-E Thickness

240 mm

Main mineral element

Lava, slate, pumice

Water storage

40% volume

Fig. 5 Photos of the southern terrace (October 2020 and 2021)

Figure 5 shows the experimental segments of green roofs and the reference segment with a gravel layer. The upper part of Fig. 5 shows the state of the vegetation 5 months after installation. The lower part of Fig. 5 documents the state of the vegetation 17 months after installation. After this time, it is possible to observe more lush vegetation of all types of plants in the case of a green roof with a higher substrate thickness (240 mm). Currently, there have been changes on the terrace. Through a sufficient amount of measured data, test segment II (reference roof with gravel layer) was replaced by a wetland roof (Fig. 6) (Chapter “Development of Hybrid Infrastructures”).

60

M. Vertal et al.

Fig. 6 Photo of the southern terrace after the transformation of TS II. into a wetland roof (September 2022)

Fig. 7 Photo of a shelter for storing material (August 2021) with green roofs and their compositions

2.2.2

Phase 2—Shelter with Three Different Compositions of Green Roof

The existing shelter is made as a steel structure with dimensions of 12 * 5.5 m and the roof structure is finished with a trapezoidal sheet. The shelter is used to store materials and tools. The design consisted of dividing the roof into three parts for the creation of a green roof with a different type of growth medium (Fig. 7): • green roll standard • green roll standard with substrate layer Bauder LBB-E • green roll standard with substrate layer Bauder LBB-E mixed with biochar After completion, a green roof with an area of 61.21 m2 is created, contributing to the increased vegetated area. At the same time, each part of the roof has its gutter with a drainpipe. Thus, it is possible to monitor the amount of water that flows from the individual parts of shelters after rain in our climatic conditions. There are other steel shelters for the storage of material on the premises, on which a green roof is also planned (Table 2).

Measuring Selected Physical Parameters of Hybrid Infrastructure Table 2 Properties of used green roof materials—Phase 2 (green area 61.21 m2 )

61

Urbanscape Sedum Mic blanket Thickness

20–40 mm

Water storage

Approx. 8 l/m2

Green Roll Thickness

40 mm

Main mineral element

Long rock mineral wool fibres

Water storage

Approx. 29 l/m2

Vegetation substrate Bauder LBB-E Thickness

40 mm

Main mineral element

Lava, slate, pumice

Water storage

40% volume

Drainage FRB-25 Thickness

20 mm

Material base

Recycled plastic

Water storage

Approx. 11.8 l/m2

Fig. 8 Visualization of the carport and composition of the roof

2.2.3

Phase 3—Carport with Green Roof

The parking lot is an open space with a paved area of 494.72 m2 . A U-shaped carport with a green roof with an area of 124.56 m2 was designed to protect cars from rain, hail, snow and overheating in the summer months (Fig. 8). The carport protects six parking spaces and two entrances of the building. The structure is designed as steel with circular cross-section columns, Z-profile beams, and a trapezoidal sheet. The green roof layers are stacked from the manufacturer Bauder, and for the growth medium was used 60 mm thick substrate. The properties of used materials are described in Table 3. Plants were planted in August 2021. For the plants to take root and survive the hot and dry days, it was necessary to irrigate the roof. Figure 9 shows the situation on the roof one year after the carport was made.

62

M. Vertal et al.

Table 3 Properties of used green roof materials—Phase 3 (green area 35.2 m2 ) Vegetation substrate Bauder LBB-E Thickness

60 mm

Main mineral element

Lava, slate, pumice

Water storage

40% volume

Drainage Bauder WSP 50 Thickness

50 mm

Material base

Expanded polystyrene with recycled content

Water storage

Approx. 10.1 l/m2

Fig. 9 Plan view of the carport (November 2022, one year after planting plants)

2.2.4

Phase 4—Extension on the West Terrace on the 2nd Floor

The extension was proposed on the second floor on the western terrace due to the expansion of the kitchen area. The structure is made as a light steel structure with a glass curtain wall façade. The ceiling structure is made of a trapezoidal sheet with a concrete overlay. The roof of the extension is an extensive green roof with a 100 mm thick substrate. The plan for the remaining part of the western terrace is to divide it into a pedestrian, extensive green and wetland roof part. The wetland part of the terrace would be divided into four successive parts—a pond (only water, without substrate mixture and plants), a wetland with a 100 mm thick substrate, a wetland with a 150 mm thick substrate and a wetland with a 200 mm thick substrate. Figure 10 illustrates the floor plan of the western terrace and roof of the extension and its structure. Table 4 describes the water storage properties of the materials used on the roof of the extension.

Measuring Selected Physical Parameters of Hybrid Infrastructure

63

Fig. 10 Floor plane of the western terrace and composition of the roof

Table 4 Properties of used green roof materials—Phase 4 (green area 19.28 m2 )

Vegetation substrate Bauder LBB-E Thickness

100 mm

Main mineral element

Lava, slate, pumice

Water storage

40% volume

Drainage Bauder DSE 20 Thickness

20 mm

Material base

HDPE

Water storage

Approx 7.4 l/m2

Fig. 11 Photo of the western terrace (November 2022, three months after planting plants)

Figure 11 shows a view of the roof of the extension three months after planting the plants. The modification of the remaining part of the terrace is planned for the year 2023.

64

2.2.5

M. Vertal et al.

Phase 5—Green Roof on the Northern Terrace on the 4th Floor

In the spring of 2023, a new experimental terrace on the fourth floor is planned. The northern terrace would consist of nine boxes, where eight different green roofs and one wetland roof would be made. From the point of view of the carbon footprint, the selection of green roof components focused on local producers, within a radius of 250 km. Most of the material (90%) proposed for the composition of the roof is produced in a factory in middle Slovakia. It has a strategic location at a distance from large cities (Banská Bystrica 89.8 km, Poprad 112 km, Košice 145 km, Nitra 174 km, Žilina 178 km, Prešov 183 km, Trenˇcín 193 km, Bratislava 250 km). Part of the roofs would be equipped with measuring infrastructure, and the remaining green roofs would be used for visual comparison of test segments.

2.2.6

Phase 6—Green Wall on the East and South Sides of the Building

The green wall is designed on the eastern and southern parts of the building to capture dust and noise from the public road on which it is oriented. The vertical garden also adds to the aesthetic value of the building. Figure 12 illustrated two current designs of the vegetation wall.

Fig. 12 Visualization of green wall alternatives, prepared by Idil Mersin during the internship: a Full covering of the facade with a green wall; b Intermittent covering of the facade with a green wall

Measuring Selected Physical Parameters of Hybrid Infrastructure

65

Fig. 13 Three-dimensional section of the proposed experimental biosolar roof

Fig. 14 Three-dimensional section of the proposed northern terrace on the second floor

2.2.7

Phase 7—Biosolar Roof

The roof of the administrative building is proposed to transform it into a green roof with a 120 mm thick substrate with photovoltaic collectors (Fig. 13). The combination of a green roof and photovoltaic collectors would have beneficial effects on both sides. By shading the collectors, wet and dry areas would be created on the roof, which would create a variety of vegetation. The vegetation layer has a cooling effect on the surrounding microclimate and thus maintains a temperature close to 20 °C around the collectors in the summer, which is the best for the panels, they work most efficiently.

2.2.8

Phase 8—Intensive Green Roof

The last phase would be completed on the north terrace on the second floor. The terrace is the largest on the building with an area of approx. 172.07 m2 and offers space to create a “park” on the building with intense greenery (Fig. 14). The substrate would be distributed unevenly, from 300 to 500 mm thick. Another wetland roof would be created in the middle of the terrace to increase biodiversity. The purpose of the terrace is mainly recreational.

2.2.9

Evaluation of the Retention Potential After the Proposed Transformation of the Building

After completion of all phases, the green area on the building would represent 82% of the entire area of the roof structure of the building. The growth of vegetation on the building has many advantages, one of them is the accumulation and the reduction in the peak flow of rainwater. In the original state, the flow of rainwater is 313.43 m3 /

66

M. Vertal et al.

year, the building is without vegetation layers. According to the standard calculation for the amount of rainwater per year is Qr (m3 /year): Q r = AHz C

(1)

where A (m2 ) is the drainage area, H z (mm) is the long-term rainfall total for the given location (621 mm/year) and C (−) is the runoff coefficient. It is possible to approximately calculate the impact of the application of green roofs on the building, from the point of view of rainwater accumulation. For comparison, the runoff coefficient for green roofs was considered according to the German standard (DIN 1986-100:201612, 2016), the Austrian standard (ÖNORM B 2501, 2016), the Slovak standard (STN 73 6760, 2009), and the FLL directive (FLL, 2008) in Table 5. Table 5 shows runoff coefficients according to various standards (DIN 1986100:2016-12, 2016; ÖNORM B 2501, 2016; STN 73 6760, 2009; FLL, 2008) in dependence on the substrate thickness. The annual amount of runoff water according to Slovak standards (STN 73 6760, 2009) and based on the height of the substrate is 167.81 m3 /year. In the case of calculation according to the Austrian standard (ÖNORM B 2501, 2016), the amount of runoff water is 130.03 m3 /year. The difference between the calculated amount of water depending on the runoff coefficient is 22.5%. In fact, it is possible that the value of the runoff water will differ depending on the types of used materials compared to the calculations according to the standards. Applying a laboratory-measured runoff coefficient specific to the green roof assembly is possible. The producer of applied green roof structures (Bauder) provided measured runoff coefficients for the composition of green roof assembly with retention element RE40 (proposed in Phase 1). The test was carried out according to the FLL standards (FLL, 2008). According to the measurements, runoff coefficients are Table 5 Rainwater flow per year according to the German, Austrian and Slovak standards and the FLL directive. Using rainwater runoff coefficient C for green roofs according to the thickness of the substrate Green area (m2 ) Phase 1

Substrate thickness (mm)

Runoff coefficient DIN 1986-100

ÖNORM B 2501

STN 75 6760

FLL

17.6

120

0.4

0.3

0.4

0.4

17.6

240

0.4

0.3

0.3

0.2

34.46

100

0.5

0.5

0.7

0.5

Phase 5

45.35

200

0.4

0.3

0.4

0.3

Phase 7

213.02

120

0.4

0.3

0.4

0.4

Phase 8

131.75

300

0.2

0.1

0.3

0.2

Non-green area

101.01

–

167.81

151.44

Phase 4

Total runoff water per year (m3 /year)

0.9 156.44

130.03

Measuring Selected Physical Parameters of Hybrid Infrastructure

67

0.11 and 0.1 for substrate thicknesses 100 mm and 120 mm. Implementing these runoff coefficients into the calculation (1) would decrease the proposed runoff to 85.22 m3 /year. On the other hand, the calculation of runoff water by the FLL directive without using data obtained from laboratory measurements is 151.44 m3 /year. This makes a difference of 44% compared to the calculation with the data obtained by laboratory measurements.

2.3 Experimental Data 2.3.1

Description of Measurements

The measurements were carried out in two circuits according to the scheme in Fig. 15. Each of the circuits is connected to the measuring data logger. Data logger AHLBORN Almemo 2890-9 (9 measuring inputs) was used to measure and record external climatic parameters. A multi-input measuring data logger AHLBORN Almemo 5690 (up to 100 measuring inputs) was used to measure the course of quantities inside the segments of experimental walls. A meteorological station Ahlborn FMD760 and a pyranometer Ahlborn FLA 628 S were installed to record external climatic conditions. The compact meteorological station uses digital sensors for measuring wind (speed, direction), precipitation (rain, snow), air temperature, atmospheric humidity, and atmospheric pressure. The parameters of the used sensors are summarized in Table 6. According to specific application requirements, the data were transformed into one-hour averages or sums. The measured data of external climate parameters for the period July 2020–April 2022 are in Fig. 16. From the period of 22 months, characteristic time periods for summer and winter were selected. Typical summer dry weather without precipitation

Fig. 15 Connection of measuring devices into the double-circuit assembly

68

M. Vertal et al.

Table 6 Technical description of used sensors Wind velocity

Atmospheric humidity

Measuring method Ultrasonic

Measuring method capacitive

Measuring range 0 to 75 m/s

Measuring range 0 to 100% RH

Resolution 0.1 m/s

Resolution 0.1% RH

Accuracy ±0.3 m/s or ±3% (0 to 35 m/s)

Accuracy sensor ±2% RH

±5% (>35 m/s) Wind direction

Atmospheric pressure

Measuring method Ultrasonic

Measuring method MEMS sensor, capacitive

Measuring range 0 to 359.9°

Measuring range 300 to 1200 hPa

Resolution 0.1 degrees

Resolution 0.1 hPa

Accuracy 1 m/s)

Accuracy sensor ±0.5 hPa (0 to +40 °C)

Precipitation, rainfall

Global radiation pyranometer

Measuring method Radar sensor

Measuring range: 0 to 1500 W/m2

Measuring range Drop size 0.3 to 5.0 mm

Resolution: 0.1 W/m2

Resolution Precipitation, liquid 0.01 mm

Spectral range: 0.3 to 3 µm

Precipitation types rain, snow Reproducibility typical >90% Air temperature Measuring method NTC Measuring range –50 to +60 °C Resolution 0.1 K (–20 to +50 °C), otherwise 0.2 K Accuracy sensor ±0.2 K (–20 to +50 °C), otherwise ±0.5 K (>–30 °C)

represents the period 17.06.2021–23.06.2021, the warm summer period is characterized by the period from 9 July 2021 to 15 July 2021. The period (16.01.2021– 21.01.2021) characterizes Cold and dry winter weather without atmospheric precipitation (rain + snow). Snowfall and the permanent occurrence of snow cover on the experimental segments are characteristic for the time period from 09 February 2021 to 14 February 2021. The first series of temperature sensors were installed under the layer of the original heat insulation. The surface temperature sensor was placed on the original waterproofing layer (position 2) in all experimental roof segments (Fig. 17). Another set of temperature sensors was installed on the main waterproofing layer of all experimental segments (position 3). The last series of sensors was installed under the substrate layers with thicknesses of 120 and 240 mm (position 4). Pt 100, class “A” sensors with a limiting deviation ± (0.15 + 0.002 |T|) K were used to measure surface temperatures in a wet environment.

Measuring Selected Physical Parameters of Hybrid Infrastructure

69

Fig. 16 Measured outdoor climate parameters for the period (July 2020–April 2022): outdoor air temperature plotted as hourly and daily average values, relative humidity (hourly and daily average), precipitation (hourly and daily sum), global solar radiation (hourly and daily average values)

3 Results and Discussion Temperature curves in experimental roofs in four characteristic periods during the year 2021 are shown in Figs. 18, 19, 20 and 21. Outdoor climate parameters are characterized by outdoor air temperature (a) (outdoor air temperature), total atmospheric precipitation (a) (precipitation), and solar radiation intensity (b) (solar radiation).

70

M. Vertal et al.

Fig. 17 Three experimental roof segments with substrate thicknesses of 120 and 240 mm and the reference segment with gravel layer. Surface temperature measurement positions are shown with numbers 2, 3, and 4

Surface temperatures T s measured at positions 2 (B2), 3 (C3), and 4 (E4) in experimental segments TSI, TS2 and TS3 are shown in parts c, d, and e in Figs. 18, 19, 20 and 21.

3.1 Summer Period A total of six summer warm sunny days are analyzed in the period from 17 June 2021 to 23 June 2021 (157 h in total). During the period, no atmospheric precipitation was recorded, the average air temperature (T e, average ) was 24.6 °C, the minimum measured temperature (T e, min ) was 16.9 °C, and the maximum temperature (T e, max ) was 31.5 °C. The curves of climate parameters are shown in Fig. 18a, b. The surface temperatures under the smaller thickness of the roof substrate (120 mm) at position 4 (Fig. 18c) are significantly higher compared to the structure with a larger thickness of the substrate (240 mm). The difference in temperature maxima measured under layers of substrates with 120 mm and 240 mm thicknesses is more than 7 K. The phase shift of the temperature maximum, which is caused by the higher thermal capacity of the vegetation layer, is also well observed. The shift of the maximum temperature under the substrate layer with a height of 120 mm compared to the maximum temperature of the outside air is approximately 1.5 h. In the case of the substrate thickness of 240 mm, the amplitude shift is 7 h. Similar courses of surface temperatures were recorded on the waterproofing layer, position 3 (Fig. 18d; Table 7). At this position, it is possible to analyze the temperature influence (efficiency) of the system composition of the vegetated roof and compare it with the reference gravel roof variant. During a hot day with a high intensity of solar radiation, there is an increase in the temperature under the gravel layer (Position C3). The surface temperature in this place often exceeds 50 °C in summer. The application of the vegetation layer reduces this temperature extreme by 14 °C at a substrate height of 120 mm and 21 °C at a substrate height of 240 mm. The difference between the minimum surface temperature (T s, min ) and the maximum surface temperature (T s, max ) under the gravel layer was 34.2 K. In the case of vegetation roofs of 120 mm

Measuring Selected Physical Parameters of Hybrid Infrastructure

71

Fig. 18 Measured climatic parameters of outdoor air temperature, precipitation, and global solar radiation for the analysed period 17 June 2021–23 June 2021 are shown in parts a, and b. Surface temperature courses measured inside experimental roofs on positions 4, 3, and 2 are graphically described in parts c, d, and e

and 240 mm, the temperature difference was reduced to 13.2 K and 3.6 K, respectively (Table 7). The hot period without precipitation was also manifested under a massive thermal insulation layer (Fig. 18e). From the course of temperatures at position 2, a continuous increase in surface temperature can be observed in all experimental segments. The roof envelope with a substrate thickness of 240 mm overheats the slowest. The sharpest increase in surface temperatures with a significant temperature amplitude can be observed in the reference roof segment with a gravel layer.

Precipitation sum (mm)

0

157

157

157

Sensor position

Outdoor

B3

C3

E3

16.9

T e, min (°C) 31.5

T e, max (°C) 24.6

T e, average (°C)

25.2

16.1

22.9

T s, min (°C)

28.8

50.3

36.1

T s, max (°C)

26.9

30.7

28.5

T s, av. (°C)

Table 7 Temperature characteristics measured inside experimental roofs during the summer hot and dry period (17 June 2021–23 June 2021)

3.6

34.2

13.2

14.6

ΔT s (°C)

72 M. Vertal et al.

Measuring Selected Physical Parameters of Hybrid Infrastructure

73

The second summer period analyzed is from July 9 to July 15, 2021 (157 h in total). This period is characterized by similar air temperatures (T e, average = 24.7 °C, T e, min = 17.8 °C, and T e, max = 33.2 °C) as the previous period. The temperature curves are shown in Fig. 19a, b. Unlike the previous period, typical summer rainy evenings were recorded during it. A cumulative rainfall of 38 mm was measured over a period of six days (Table 8). Rainwater naturally cools the segments of the experimental roofs (Fig. 19c). The amount of water from precipitation is accumulated by layers of the substrate. The

Fig. 19 Measured climatic parameters of outdoor air temperature, precipitation, and global solar radiation for the analysed period 09 July 2021–15 July 2021 are shown in parts a, and b. Surface temperature courses measured inside experimental roofs on positions 4, 3, and 2 are graphically described in parts c, d, and e

16.6 23.8

24.7

T s, min (°C)

E3

33.2

T e, average (°C)

C3

17.8

T e, max (°C) 21

38

Outdoor

T e, min (°C)

B3

Precipitation sum (mm)

Sensor position

27.3

42.9

30.4

T s, max (°C)

25.8

27.3

25.5

T s, av . (°C)

Table 8 Temperature characteristics measured inside experimental roofs during the summer hot and rainy period (09 July 2021–15 July 2021)

3.5

26.3

9.4

19.2

ΔT s (°C)

74 M. Vertal et al.

Measuring Selected Physical Parameters of Hybrid Infrastructure

75

difference in temperature maxima measured under layers of substrates (position 4) with 120 mm and 240 mm thicknesses is 3 K. The influence of atmospheric precipitation on the course of surface temperatures is also reflected on the waterproofing layer (position 3) (Fig. 19d; Table 8). The water that is in the layers of the experimental segments participates in lowering the surface temperatures of individual parts of the roof layers. The surface temperature of the reference segment with the gravel layer did not exceed 43 °C. The difference between T s, min and T s, max under the gravel layer is 26.3 K. While in the case of a roof with a substrate of 240 mm, the influence of the presence of water is minimal, in the case of a roof with a substrate thickness of 120 mm, it significantly reduces surface temperatures in individual layers. The rainy season moderated the increase in temperature in all experimental segments. This fact was also manifested under the thermal insulation layer at position 2 (Fig. 19e). Similar to the period without precipitation, the lowest surface temperature was measured in the roof envelope with a substrate thickness of 240 mm.

3.2 Winter Period The period from 16 January 2021 to 21 January 2021 (132 h) was selected for the analysis of the winter season. This period is represented by cold weather with characteristics of outdoor air temperature (T e, average = −4.6 °C, T e, min = −9.8 °C, and T e, max = 2.5 °C) without atmospheric precipitation. During frosty days without snow cover, the substrate layer eliminates the frost penetration into the roof structure (Fig. 20c). The night air temperature that drops below −9 °C will be reflected in the surface temperature under the substrate layers at position 4. During the coldest hours of the analyzed period, the surface temperature under the substrate with a thickness of 120 mm dropped to −1.3 °C. Temperature oscillations under the substrate with a thickness of 240 mm did not exceed 0.2 K. The drop in surface temperature on the waterproofing layer (position 3) during freezing days without snow cover on the reference roof with a gravel layer is well observable in Fig. 20d and in Table 9. The surface temperature dropped to −8.3 °C at this location, while the surface temperatures under the substrates oscillated around 0 °C. During the whole analyzed period, the surface temperature under the gravel layer copies the outside air temperature. Under the thermal insulation at position 2, the highest temperature was measured in the experimental construction with a substrate height of 240 mm (Fig. 20e). For the climatic region of Košice, the period at the turn of January and February is characterized by cold weather with a gradual increase in atmospheric precipitation, at low temperatures with snow. This weather well characterizes the period from 09 February 2021 to 14 February 2021 (132 h). On 9 February 2021, gradual cooling with a cloudy sky brought snowfall in the evening. The all-day freezing weather ensured the maintenance of the snow cover and at the same time created the basis for

76

M. Vertal et al.

Fig. 20 Measured climatic parameters of outdoor air temperature, precipitation, and global solar radiation for the analysed period 16 January 2021–21 January 2021 are shown in parts a, and b. Surface temperature courses measured inside experimental roofs on positions 4, 3, and 2 are graphically described in parts c, d, and e

its increase. During the analyzed period from 09 February 2021 22:00 to 14 February 2021, there was a continuous snow cover on the experimental roof segments. The first half of the analyzed period was characterized by air temperatures around 0 °C and snowfall. The height of the snow cover on February 11 in the evening reached 42 mm. The effect of snow cover on the course of surface temperatures at position 4 is shown in Fig. 21c. The measured surface temperatures under the substrate layers with a height of 120 and 240 mm range from 0 to 1 °C regardless of the outside air temperature.

Measuring Selected Physical Parameters of Hybrid Infrastructure

77

Fig. 21 Measured climatic parameters of outdoor air temperature, precipitation, and global solar radiation for the analysed period 09 February 2021–14 February 2021 are shown in parts a, and b. Surface temperature courses measured inside experimental roofs on positions 4, 3, and 2 are graphically described in parts c, d, and e

The surface temperatures measured on the waterproofing layer (position 3) are shown in Fig. 21d and summarized in Table 10. The influence of the snow cover layer moderates the surface temperatures under the substrate and gravel layers. Despite the cooling on 11 February in the evening, the surface temperature under the gravel layer oscillates around 0 °C. Even cooling down to −10 °C was not manifested by a drop in the surface temperature under the gravel layer. Several days of freezing weather with air temperatures below −14 °C and low intensity of solar radiation caused a decrease in the surface temperature under the gravel layer to −

0.9

1.1

−0.1

−8.3

E3

T s, max (°C)

C3

−4.6

T s, min (°C)

0.2

2.5

−9.8

T e, average (°C) −1.3

3

Outdoor

T e, max (°C)

T e, min (°C)

B3

Precipitation sum (mm)

Sensor position

1.0

−4.6

−0.5

T s, av. (°C)

0.2

8.2

1.5

12.3

ΔT s (°C)

Table 9 Temperature characteristics measured inside experimental roofs during the winter cold and dry period 16 January 2021–21 January 2021

78 M. Vertal et al.

1.1

1.3

0.1

−2.8

E3

T s, max (°C)

C3

−5.0

T s, min (°C) 0.4

1

−14.4

T e, average (°C) 0.2

35

Outdoor

T e, max (°C)

T e, min (°C)

B3

Precipitation sum (mm)

Sensor position

1.2

−0.4

0.4

T s, av. (°C)

0.2

2.9

0.2

19.4

ΔT s (°C)

Table 10 Temperature characteristics measured inside experimental roofs during the winter cold and snowy period 09 February 2021–14 February 2021

Measuring Selected Physical Parameters of Hybrid Infrastructure 79

80

M. Vertal et al.

2.8 °C. During the analyzed period, despite the low air temperatures, there was no significant drop in surface temperatures under both substrates of the vegetation roofs. The presence of a continuous layer of snow during the analyzed period was reflected in the course of surface temperatures under the thermal insulation (position 2). The measured surface temperatures of the studied segments show only minimal differences (Fig. 21e).

4 Conclusions This chapter presents the gradual transformation of the area in the industrial zone of the city of Košice to a zone with applied elements of the sponge city. The project was created based on the cooperation of the private and university sectors. The symbiosis of such functioning brought the implementation of several visions of sponge cities on the building or its immediate surroundings. By the end of 2022, the following were implemented: • experimental vegetation roofs with different heights of roof substrates in combination with a reference roof (Phase 1), • experimental shelters and temporary roofs (for example, warehouses) with the application of green roofs (Phase 2), • experimental shelters for parking cars, bicycles, scooters (Phase 3), • experimental green roof above the kitchen extension (Phase 4 partly). After two years of running, it can be concluded that all the tested and implemented structures can survive and thrive in the climatic conditions of the selected location without supplied external irrigation. Vegetation thrives significantly better on a roof with a higher layer of the substrate. This is due to the better possibility of developing the root system of individual plants as well as the higher retention capacity of the thicker substrate layer. Mitigation of water runoff from vegetated roofs is moderated primarily by the substrate layer and the retention system element of the roof. A protection and filtration membrane performs the additional water storage in the roof. According to the manufacturer’s data of the used roof components, it is possible to achieve a runoff coefficient of up to 0.1 when the thickness of the used substrate is 120 mm. By using a larger substrate thickness (for example 240 mm), it is possible to reduce the value of the runoff coefficient to a number smaller than 0.1. Applying elements of the sponge city will bring: • significant reduction of the rainwater sewerage load during a flash flood and long-term rain events, • retention of the maximum possible amount of rainwater in the roof envelope, • a secondary, longer-lasting evapotranspiration period during which the effect of heat islands is mitigated, • catching a substantial amount of rainwater for the development of vegetation.

Measuring Selected Physical Parameters of Hybrid Infrastructure

81

The experimental data clearly show the positive benefits of green roofs for temperature distribution in roof envelopes. In the summer, the overheating of the layers of roof constructions and the shift in the amplitude of temperature maxima are eliminated. The positive effect of a green roof is enhanced by the presence of water in its upper layers. The higher heat storage capacity of the wet substrate and the drop in the temperature of the surface layers of the substrate due to evapotranspiration moderate the temperatures in the roof shell of the building and have a positive effect on the surroundings of the roof. In winter, the green roof protects the building from excessive cooling. With a well-insulated roof envelope (at the level of current European legislation), water in the substrate of the roof construction does not cause its fundamental cooling. On the contrary, in the case of continuous snow cover on the experimental segments, it is possible to observe additional thermal protection of the roof structure on the green roofs as well as on the reference gravel roof. In the first quarter of 2023, the implementation of nine new experimental segments of green and wetland roofs is planned (Phase 5). The roofs will be designed in terms of reducing the carbon footprint of new and renovated buildings. Up to 95% of the weight of the vegetation roof layers will be realized from local sources brought from a distance of up to 250 km. By applying all the phases described in this chapter, the number of green roofs and terraces in the experimental building will increase to 82%. At the same time, the applied elements of the sponge city become experimental constructions for the works of university students and young researchers. Acknowledgements The authors are grateful for the support of the Slovak Research and Development Agency APVV-18-0360 “Active hybrid infrastructure towards to a sponge city”.

References Almeida, A. P., Liberalesso, T., Silva, C. M., & Sousa, V. (2021). Dynamic modelling of rainwater harvesting with green roofs in university buildings. Journal of Cleaner Production, 312, 127655. https://doi.org/10.1016/j.jclepro.2021.127655 Cakyova, K., Vertal, M., Vystrcil, J., Nespesny, O., Beckovsky, D., Rubina, A., Pencik, J., & Vranayova, Z. (2021). The synergy of living and water wall in indoor environment—Case study in city of Brno, Czech Republic. Sustainability, 13(21), 11649. https://doi.org/10.3390/su1321 11649 Chan, F. K. S., Griffiths, J. A., Higgitt, D., Xu, S., Zhu, F., Tang, Y.-T., Xu, Y., & Thorne, C. R. (2018). “Sponge City” in China—A breakthrough of planning and flood risk management in the urban context. Land Use Policy, 76, 772–778. https://doi.org/10.1016/j.landusepol.2018.03.005 Chen, P.-Y. (2022). Effects of meteorological variables and substrate moisture on evapotranspiration and thermal performance of a green roof in a subtropical climate. Ecological Engineering, 180, 106663. https://doi.org/10.1016/j.ecoleng.2022.106663 DIN 1986-100:2016-12. (2016). Entwässerungsanlagen für Gebäude und Grundstücke (in German).

82

M. Vertal et al.

European Commission, Directorate-General for Research and Innovation. (2021). Evaluating the impact of nature-based solutions: A handbook for practitioners. Publications Office of the European Union. https://data.europa.eu/doi/10.2777/244577 FLL. (2008). Guidelines for the planning, construction and maintenance of green roofing. Forschungsgesellschaft Landschaftsentwicklung Landschaftsbau e.V. Jamei, E., Chau, H.W., Seyedmahmoudian, M., & Stojcevski, A. (2021). Review on the cooling potential of green roofs in different climates. Science of the Total Environment, 791, 148407. https://doi.org/10.1016/j.scitotenv.2021.148407 Karlsson, I. B., Sonnenborg, T. O., Refsgaard, J. C., Trolle, D., Børgesen, C. D., Olesen, J. E., Jeppesen, E., & Jensen, K. H. (2016). Combined effects of climate models, hydrological model structures and land use scenarios on hydrological impacts of climate change. Journal of Hydrology, 535, 301–317. https://doi.org/10.1016/j.jhydrol.2016.01.069 Liu, H., Kong, F., Yin, H., Middel, A., Zheng, X., Huang, J., Xu, H., Wang, D., & Zhihao Wen, Z. (2021). Impacts of green roofs on water, temperature, and air quality: A bibliometric review. Building and Environment, 196, 107794. https://doi.org/10.1016/j.buildenv.2021.107794 Liu, W., Qian, Y., Yao, L., Feng, Q., Engel, B. A., Chen, W., & Yu, T. (2022). Identifying cityscale potential and priority areas for retrofitting green roofs and assessing their runoff reduction effectiveness in urban functional zones. Journal of Cleaner Production, 332, 130064. https:// doi.org/10.1016/j.jclepro.2021.130064 Motlagh, S. H. B., Pons, O., & Hosseini, S. M. A. (2021). Sustainability model to assess the suitability of green roof alternatives for urban air pollution reduction applied in Tehran. Building and Environment, 194, 107683. https://doi.org/10.1016/j.buildenv.2021.107683 Niemets, K., Kravchenko, K., Kandyba, Y., Kobylin, P., & Morar, C. (2021). World cities in terms of the sustainable development concept. Geography and Sustainability, 2(4), 304–311. https:// doi.org/10.1016/j.geosus.2021.12.003 ÖNORM B 2501. (2016). Entwässerungsanlagen für Gebäude und Grundstücke – Planung, Ausführung und Prüfung. Austrian Standards International – Standardisierung und Innovation (in German). Poórová, Z., & Vranayová, Z. (2019). Green roofs and water retention in Košice, Slovakia (1st ed.). Springer Nature - 2020. - 133 s. [print]. ISBN 978-3-030-24038-7. https://doi.org/10.1007/9783-030-24039-4 Pumo, D., Francipane, A., Alongi, F., & Noto, L. V. (2023). The potential of multilayer green roofs for stormwater management in urban area under semi-arid Mediterranean climate conditions. Journal of Environmental Management, 326(Part A), 116643. https://doi.org/10.1016/j. jenvman.2022.116643 STN 73 6760. (2009). Kanalizácia v budovách—Drainage systems inside buildings (in Slovak). Stovin, V., Vesuviano, G., & Kasmin, H. (2012). The hydrological performance of a green roof test bed under UK climatic conditions. Journal of Hydrology, 414–415, 148–161. https://doi.org/10. 1016/j.jhydrol.2011.10.022 Vertaˇl, M., Zozulák, M., Vašková, A., & Korjenic, A. (2018). Hygrothermal initial condition for simulation process of green building construction. Energy and Buildings, 167, 166–176. https:// doi.org/10.1016/j.enbuild.2018.02.004

Prioritization of Sustainability Dimensions and Indicators for Office Buildings Eva Krídlová Burdová , Silvia Vilˇceková , and Katarína Harˇcárová

Abstract According to the European Green Deal, climate change and environmental degradation pose an existential threat to Europe and the world. To tackle this problem, Europe needs a new growth strategy that is transforming the EU into a modern and competitive, resource-intensive economy, with zero net greenhouse gas emissions by 2050, whereby economic growth will be decoupled from resource use. As is well known, the construction and operation of buildings are main consumers of energy and material resources and significant polluters of the environment during all stages of their life cycle, so this chapter focuses on the analysis of buildings from environmental and social aspects. The chapter presents the latest knowledge concerning sustainable construction and sustainability assessment of buildings. Detailed analysis of environmental impacts with the goal of prioritization of sustainability dimensions and indicators of office buildings are presented. Three office buildings are subjected to analyses of environmental indicators using life cycle assessment (LCA) methodology and indoor environmental quality (IEQ) through the monitoring of IEQ factors. One Click LCA platform was chosen for the analysis of environmental impact categories and IEQ was evaluated through short-term measurement of physical and chemical factors. Results of environmental impacts shows that buildings materials such as reinforcement steel (rebar), ready mis concrete, XPS insulation and glass façade contribute mostly to the GWP. Based on the results of the IEQ monitoring, it can be concluded that the indoor environment in assessed office buildings meets the Slovak legislative requirements as well as the requirements set by WELL and LEED v4.1 certification systems. E. Krídlová Burdová (B) · S. Vilˇceková Institute of Sustainable and Circular Construction, Faculty of Civil Engineering, Technical University of Kosice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected] S. Vilˇceková e-mail: [email protected] K. Harˇcárová Institute of Architectural Engineering, Faculty of Civil Engineering, Technical University of Kosice, Vysokoskolska 4, 042 00 Kosice, Slovakia e-mail: [email protected] © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 Z. Vranayova et al. (eds.), Sponge City Hybrid Infrastructure, Earth and Environmental Sciences Library, https://doi.org/10.1007/978-3-031-38766-1_5

83

84

E. Krídlová Burdová et al.

Keywords Climate change · Sustainability · Office buildings · Environmental indicators · IEQ

1 Introduction Climate change and environmental degradation pose an existential threat to Europe and the world. Therefore, Europe needs a new growth strategy to transform the EU into a modern, competitive, resource-efficient economy with zero net greenhouse gas emissions by 2050. Economic growth will be decoupled from resource use, and no individual or region will be forgotten. The European Green Deal represents a major effort by the EU to transition to a sustainable and climate-neutral economy, and to position itself as a global leader in the fight against climate change and environmental degradation. The European Green Agreement sets out an action plan to promote resource efficiency by transitioning to a clean circular economy, restoring biodiversity and reducing pollution. The plan also describes the necessary investments and the financial instruments available. It also explains how to ensure a just and inclusive transformation. The fact that the European Union aims to be climate neutral by 2050 is very significant. To make this political commitment legally binding, European climate legislation has been proposed and implemented. To achieve it, actions in all sectors of economy are required. These include investing in innovative and green technologies; promoting innovation in industry; introducing cleaner, cheaper and healthier forms of private and public transport; decarbonising the energy sector and ensuring high energy efficiency in buildings. In addition, cooperation with international partners is also essential in order to improve global environmental quality standards. The EU will also provide financial support and technical assistance to those most affected by the transition to a green economy. This is the so-called fair transformation mechanism to help mobilize at least e 100 billion in the most affected regions between 2021 and 2027 (The European Green Deal). The construction and operation of buildings are major consumers of energy and material resources and create major drain on energy and material resources and contribute to significant pollution of the environment during all stages of their entire life cycle. According to the International Energy Agency (IEA, 2019), buildings were responsible for 36% of total energy consumption in 2018 and contributed up to 39% of global annual greenhouse gas emissions. Of these, 11% were the result of the production of building materials and products such as steel, cement and glass (IEA, Global Status Report for Buildings and Construction 2019). For this reason, high performance, green and zero energy buildings are designed to be mainly energy and carbon neutral. It is important to point out that design stage of a building has great potential for saving resources, reducing energy consumption and mitigating the impact on the environment, as decisions at this stage will affect the efficiency of the whole life cycle of a building (Kovacic & Zoller, 2015). Decisions at this stage of the building design focus on maximizing the use of natural resources and improving

Prioritization of Sustainability Dimensions and Indicators for Office …

85

residents’ comfort. It is also called climate-responsive design (Alajmi et al., 2018; Chen & Yang, 2018; Wan et al., 2020). The life cycle of a building includes several stages, including raw material extraction, manufacturing of building materials, construction, operation, and demolition or renovation. Each stage of the life cycle can have negative environmental impacts, including depletion of non-renewable resources, pollution, and contamination, excessive water consumption, and impacts on indoor and outdoor air quality. The design of a building is a critical stage in the life cycle, as it sets the foundation for the construction and operation of the building. A comprehensive evaluation of the building design is needed to assess the negative impacts on the indoor environment and surroundings. This evaluation should consider not only environmental impacts but also social and economic aspects, as buildings can have significant impacts on the well-being of occupants and communities, as well as on the economy. To assess the environmental, social, and economic impacts of buildings, integrated tools are needed that can evaluate the building design and operation holistically. These tools should consider factors such as energy efficiency, water conservation, indoor air quality, waste reduction, and social equity. By using such tools, designers and builders can identify opportunities to reduce negative impacts and create more sustainable buildings that meet the needs of occupants and communities while minimizing environmental impacts. The evaluation of buildings from environmental, social and economic performance has become the subject of great debate in the Slovak Republic in recent years. The purposes of the assessment are: determination of the construction of buildings in terms of safety and reliability, determination of the impact on the environment and climate change and finding the measures leading to the building’s sustainability. The societal purpose is to design buildings in accordance with the goals of sustainable development. However, the design of sustainable buildings is a targeted process in which all the sustainability criteria must be considered during all life cycle stages. Several international documents and declarations define the basic requirement for sustainable development. One of the basic documents creating the framework for sustainable construction is Agenda 30. Deterioration tasks related to the sustainable construction are included in the sustainability assessment methods and systems. So, it is appropriate to say that in the last decades, environmental assessment systems, methods and tools have been developed and used in many countries. A sustainability or green assessment system is a specific complex of activities aimed at systematic and objective building performance assessment. These processes lead to the design, construction and operation of buildings with regard to meeting the criteria of sustainable development. The environmental assessment of a building is not only a tool for control, but also a tool for sustainable building design. The purpose of the building’s evaluation is to determine the actual condition of buildings in terms of safety and reliability, give options for comparing buildings, finding the impact of buildings on the environment and proposing measures leading to sustainable construction (Vilˇceková & Burdova, 2008a, 2008b, 2008c, 2008d, 2010a, 2010b). Building sustainability assessment methods reflect the importance of the concept of sustainability in the design of buildings and civil engineering structures. The main

86

E. Krídlová Burdová et al.

role of sustainability assessment methods is to provide a way to assess the environmental performance of a building using a common and verifiable set of criteria. The main objective is to achieve higher environmental, social and economic standards. Environmental awareness of construction procedures is also increased and the basic direction of the construction industry to protect the environment and achieve the goals of sustainable development is determined (Cole, 1999; Ding, 2008). Assessment of Different building systems approach this task from a slightly different perspective, but they have certain elements in common. Most, if not all, deal with site selection criteria in one way or another, the efficient use of energy and water resources during construction work, waste management during construction and operation, the quality of the indoor environment, transport service requirements and environmental choice, and preferred materials (Trusty & Horst, 2002). The assessment of a building’s environmental performance covers a wide range of issues and may include several environmental and economic, social and cultural factors. So, sustainability assessment of buildings requires multidisciplinary and multicriteria approach in the cooperation of architects, designers, civil engineers, specialists, environmentalists, building owners and users, and others. As for the assessment tools, there are many of them in the world. They are used for the assessment of building materials, buildings structures and for the entire buildings. They cover different phases of a building’s life cycle and take into account different environmental issues. They are global, national and in some cases local. Several national tools can be used as global tools by changing national databases. The tools are being developed for various purposes, such as research, consultation, decisionmaking and maintenance. These aspects lead to different users such as designers, architects, researchers, consultants, owners, tenants and authorities. Various tools are used to evaluate new and existing buildings (Haapio & Viitaniemi, 2008). When assessing the parameters of buildings, the scope of the environmental assessment extends from a criterion, such as the economic performance of buildings, to the full integration of all aspects arising during the lifetime of the building and its elements. Therefore, the term “Sustainable Building” is a broad multi-criteria subject related to three basic interrelated parameters: economic, environmental and social (Dimitris et al., 2009; Mwasha et al., 2011). In order to identify these indicators that affect the ability of building performance assessment models, a comprehensive survey of construction professionals was conducted using a questionnaire survey technique, while the data were analyzed using the Analytical Hierarchy Process (AHP) (Dimitris et al., 2009). By integrating the building with the assessment tool to minimize the impact on natural resources, we can maximize human comfort and social ties. The development footprint should increase the existing biodiversity and ecology of the site by strengthening the existing natural patterns of the sites and connecting with the surrounding site. According to a study (Lee et al., 2007), the weighting of evaluation criteria is at the heart of all evaluation systems, as it will dominate the overall performance score of the building being evaluated. An appropriate evaluation tool must allow the designer to take into account the sensitivity of these factors in a simple and multiple analysis, together with the sensitivity of the weighting of the criteria (Soebarto & Williamson, 2001). Identifying indicators requires a consistent method

Prioritization of Sustainability Dimensions and Indicators for Office …

87

of solving multicriteria decision-making problems associated with the selection and prioritization of evaluation policy. Since the 1990s, environmental assessment methods have been extensively developed, many of which have later achieved considerable success (Alzami & Rezguri, 2020; Cole, 2006; Seo et al., 2005; Todd, 2001). The BREEAM method was the first real experiment and subsequently various schemes emerged, such as the Sustainable Building Facility (SBTool), Energy and Environmental Design Guidance (LEED) and the Comprehensive Building Environmental Assessment System (CASBEE). Almost all environmental assessment methods have been designed to suit a specific area. Evidence suggests (Alzami & Rezguri, 2020; Cooper, 1999; Crawley & Aho, 1999) that existing environmental assessment methods have been developed for various local purposes and are not fully applicable in all regions. More specifically, certain environmental factors may prevent the direct application of any existing environmental assessment. Examples of such factors are: climatic conditions; geographical characteristics; the potential of renewable energy; resource consumption (such as water and energy); used building materials and techniques; building funds; government policy and regulation; assessment of historical value; population growth; public awareness (Alzami & Rezguri, 2020). More and more environmental assessment systems and tools are being developed for the construction sector. The most important global building assessment systems are listed in Table 1 (Alazami; Cole, 1999; Cole, 2006; Estimada; Fadhlin, 2017; Haapio & Viitaniemi, 2008; LEED, 2019; Well). The aim of this chapter is to analyze the impact of three certificated office buildings on the environment using the methodology of life cycle assessment and indoor environmental quality. LCA was evaluated using One Click LCA platform and IEQ was evaluated through short-term measurement of physical and chemical factors. Based on the results, conclusion about prioritization of sustainability dimensions and indicators for office buildings is presented.

2 Methods and Materials 2.1 Study Area 2.1.1

Office Building: BASTION Office Center, Kosice

The newly built office building BASTION situated in the centre of Košice in eastern Slovakia is evaluated from IEQ and LCA analysis. This building has become the second LEED Gold-certified building in Košice. The office building is designed as a ten-storey reinforced concrete skeleton, with three underground and seven above-ground floors. The construction height of the underground floors is 2.8, resp. 3.35 m, the construction height of the entrance floor—ground floor—is 4.2 m and the construction height of the other above-ground floors is 3.7, resp. 3.6 m.

88

E. Krídlová Burdová et al.

Table 1 World environmental assessment systems (Alazami; Cole, 1999; Cole, 2006; Estimada; Fadhlin, 2017; Haapio & Viitaniemi, 2008; LEED, 2019; Well) System

Country

Year

Main categories for buildings Certification levels

BREEAM UK/ (Building Research International Establishment Environmental Assessment Method)

1990

Management, Health and well-being, Energy, Transport, Water, Materials, Waste, Land use and ecology, Pollution, Innovation

Pass Good Very good Excellent Outstanding

Green Globes

2004

Project management, Site, Energy, Water, materials and resources, Emissions, Indoor environment

One Green Globes Two Green Globes Three Green Globes Four Green Globes

LEED (Leadership USA/ in Energy and International Environmental Design)

1998

Location and transportation, Sustainable sites, Water efficiency, Energy and atmosphere, Materials and resources, Indoor environmental quality, Innovation, Regional priority

Certified Silver Gold Platinum

SBTool

28 countries

1996

NABERS

Australia

2001

Energy, Water, Waste, Indoor 1–6 stars environment

BEAM (Building Environmental Assessment Method)

Hong Kong

2009

Site aspects Material aspects Water use Energy use Indoor environmental quality Innovations and additions

Bronze Silver Gold Platinum

CASBEE

Japan

2001

Energy efficiency Resource efficiency Local environment Indoor environment

_S _A _B+ _B _C

SABA (Green Building Rating System)

Jordan

2008

Site, Energy efficiency, Water efficiency, Material, Indoor environment quality, Waste and pollution, Cost and economic

Performance levels (very green [100–80%], green [79–50%], not green [