NBSINFRA City Labs Booklets: Prague

Prague City lab Booklet Czechia Funded by the European Union 2 Table of contents Introduction All the City Labs Implementation Evaluation and Monitoring Key activities Best practices 6 3 7 9 10 11 Authors Acknowledgments Michal Sněhota Licia Felicioni Pavlína Žatecká Barbora Hejtmánková Sagnik Bhattacharjee Jiří Tencar ECOTEN urban comfort Vladimíra Jelínková Petra Marešová Marek Petreje Czech Technical University in Prague 3 All the City Labs The NBSINFRA project has five city labs across Europe that are assessing how cities can handle different challenges and stay resilient through Nature-Based Solutions. Each city lab aims to investigate how NBS can protect local infrastructure, preserve biodiversity, restore ecosystems and confront the challenges of climate change. The goal is to deliver tailored solutions and risk indicators for specific locations, contribute to city contingency plans and increase the resilience and sustainability of NBS for future generations. Cologne Germany Fingal Ireland Ruse Bulgaria Aveiro Portugal Prague Czechia 4 Visit our website for a more accurate insight on the project’s city labs www.nbsinfra.eu Nature Based Solutions stages across City Labs Collaborative assessment of the current conditions and identification of key challenges and opportunities. Co-designing and co-creating nature-based solutions with input from diverse stakeholders. Collaborative implementation of the solutions, ensuring active participation from all involved parties. Ongoing evaluation and monitoring of the solutions effectiveness through collective input and feedback. Expanding or replicating the solutions collaboratively to ensure broader impact and scalability. (Co-) Diagnosis and (Co-) Characterization (Co-) Design and (Co-) Creation (Co-) Implementation (Co-) Evaluation and (Co-) Monitoring (Co-) Amplification or (Co-) Replication 1 2 3 4 5 Fingal Ireland NBS stages: 1-2 Cologne Germany NBS stages: 4 Ruse Bulgaria NBS stages: 1 Aveiro Portugal NBS stages: 1-2 Prague Czechia NBS stages: 3-4 5 Prague Czechia 6 These include the University Centre for Energy Efficient Buildings (UCEEB) of the Czech Technical University (CTU) in Buštěhrad, where green roofs with various layering and substrates, rooftop constructed wetlands, and bioretention cells are studied; the CTU University Campus where green roofs are implemented along with other urban greenery; and Českobrodská High School, featuring a green roof, green façade, and blue infrastructure for rainwater and greywater management. Historical data have identified The City Lab of Prague includes three distinct locations where nature-based solutions (NBS) are tested and evaluated under real-world conditions. Introduction extreme heat and heat waves as primary hazards in Prague and its surroundings. Detailed simulations on the urban heat vulnerability are run to spot the most prone areas to potentially select the most suitable solutions to create a more balanced and sustainable urban landscape. For each site, a comprehensive stakeholder mapping analysis has been conducted to identify those who would be impacted by and benefit from the implementation of NBS, as well as those responsible for granting approval. 7 Implementation Specific activities have been carried out to identify the most suitable NBS for each location, considering environmental conditions and urban challenges. Ecosystem mapping Urban heat vulnerability From May to September 2024, plant species monitoring was conducted at three City Lab Prague locations. The survey assessed biodiversity and ecological functions, identifying a mix of native species, ruderal plants, and invasive species. The findings highlight the role of green spaces in enhancing biodiversity, sustainability, and climate resilience. An urban heat vulnerability map was created using Earth observation data and Czech census information, covering the entire city of Prague. This includes all the City Lab sites, except for the UCEEB Building, which is located in Buštěhrad, outside Prague’s administrative boundaries. 8 Assessing Prague’s urban heat vulnerability using the IPCC framework involves three key components: exposure, sensitivity, and adaptive capacity. Exposure map: Heat Vulnerability Map: Sensitivity Map: Adaptive Capacity Map: These indices are combined to calculate the Urban Heat Vulnerability Index. Higher UHVI values indicate greater vulnerability, helping to pinpoint priority areas for intervention in Prague. Exposure measures the intensity of urban heat using satellite data and historical temperature records, mapping areas with extreme heat over multiple years. Sensitivity identifies vulnerable populations (children, elderly, and healthcompromised individuals) based on census and demographic data. Adaptive Capacity evaluates green and blue infrastructure (vegetation, water bodies) using satellite indices and GIS data to assess heat mitigation potential. 9 Evaluation and Monitoring The City Lab focuses on various sites where NBS have already been implemented, aiming to assess their impacts and benefits on buildings and their surroundings, particularly in terms of thermal performance, as well as air quality and water retention. In particular, the primary NBS and associated technologies installed at CTU UCEEB have been monitored since the project’s start. Green roof Hybrid roof Infiltration swales The monitoring activity revealed that green roofs with dense vegetation and finer substrate exhibited superior water retention and maintained lower temperatures compared to those with sparse vegetation and coarser substrates, thereby creating a more favourable environment. The monitoring activity showed that hybrid green roofs, which integrate constructed wetlands and green roofs, effectively treat greywater and regulate temperatures. These systems significantly reduce surface temperatures, manage stormwater, and enhance urban thermal comfort through evapotranspiration. The monitoring activity demonstrated that the Bioretention Cell, constructed to manage stormwater runoff from a roof, has the potential to mitigate peak stormwater flows, reducing runoff by up to 97%. This highlights their effectiveness in controlling stormwater.