​CoolINN Green Oasis

​Innsbruck is a city nestled in the Alps. Due to its geographical location, it is a densely built-up city that, apart from the rivers Inn and Sill, has had little blue and green infrastructure to counteract the effects of climate change.
For urban heat island mitigation, the City of Innsbruck launched the "cool-INN" project in the summer of 2020 together with Innsbruck’s municipal IKB, the University of Innsbruck, and the University of Natural Resources and Life Sciences, Vienna (BOKU). The aim was to improve the quality of stay in an existing park, the exhibition park on Ing.-Etzel-Straße. Prior to the project, the triangular park included a kiosk building, nine large trees, and a central asphalt area with benches surrounded by green space, and was only little used. With a new design and expansion of the park area, a central water landscape was established to cool the area, making it more comfortable for visitors, especially during hot days. The new design of the park not only promotes social interaction, but pedestrian and cyclist use while reducing car traffic.
This project is also an example of how to adapt or transform existing urban spaces and infrastructure to better address the challenges of climate change, such as increasing temperatures and extreme weather events.

- ​Expansion of green infrastructure:
- almost doubling of green area allowing rainwater to seep into the ground and also increasing evaporation (and associated cooling) to take place
- ​expansion of the tree population by 18 trees and by that increasing their shading and evapotranspiration function

- ​Establishment of blue infrastructure (see “Technical aspects”)

- ​Public participation campaign (see “Community engagement”) in order to integrate and cater for park user needs and increase acceptance

- ​The walking and cycling surfaces were made of water-permeable drainage concrete and for the seating areas water-bound paving was used. Both allow for local infiltration and evaporation.

- ​Changes to the surrounding street layout, prioritizing pedestrian and cyclist access. A formerly car-dominated street was converted into a pedestrian and cyclist-only zone, enhancing safety and encouraging active transportation

- ​By use of red, grey and beige tones, reflection instead of storage of heat was favoured
- ​Installation of a central water feature, drinking fountain ground nozzles and a spray mist for provision of evaporative cooling as well as a small grindle
- ​Installation of nine leatherwood trees in a sponge city system with adjacent rain garden drainage basins
- ​The hilly design allows for a variety of seating and lounging options, as well as play areas for children. Elevated seating is particularly appreciated by parents, as it offers a better view of children playing.
- ​Diverse seating options around the water areas with wooden surfaces with air slits to facilitate air circulation in the seating and backrest areas
- ​Provision of a small event area and other park furnishings, including two picnic tables, to provide spaces for socializing or relaxing

​A public participation campaign was organised parallel to the implementation activities, including:

- ​Surveys of residents and passersby and observations on hot summer days and an online survey with tenants to better understand user behaviour and needs
- ​Discussions/Exchange meetings with official stakeholders owning neighbouring buildings/areas
- ​A 5-day workshop with children
- ​The opening of the park was celebrated with a festive event attended by local officials and project partners. The park hosted a series of events called "Klimasalon" until the end of August to encourage residents to enjoy the new space

​Micro- and Bioclimatic Monitoring:
- The cooling effects within the park are noticeable and measurable, but they are localized and do not extend beyond the park's boundaries.
- ​Integrating such cooling concepts into urban planning can have broader impacts on the city level.
- ​Individual "cooling oases" are socially important, providing retreats for people without access to private outdoor spaces or whose homes overheat in summer.

​Social Monitoring:
- ​Water installations and "experienceable water" significantly enhance the quality of stay and recreational value of urban parks.
- ​This psychological cooling effect encourages people to spend more time outdoors, improving urban living quality.
- ​The project effectively informed and engaged the public about climate change, its impacts, and adaptation measures, notably through the "Klimasalon" initiative.

​Operational Monitoring:
- ​Graphical representation of operational data is crucial for monitoring and identifying issues, aiding operational staff in maintaining oversight.
- ​Simple and cost-effective sensors, like level and conductivity sensors, provide valuable information when graphically presented.

​Microbiological Monitoring:
- ​Surface runoff water collected in sediment traps shows significant microbiological contamination, with elevated levels of fecal indicators (E. coli and enterococci), suggesting potential pathogen presence.
- ​Direct reuse of collected water is not recommended due to exceeding bathing hygiene regulations.
- ​Treatment with sand filters and UV systems proved effective, meeting hygiene standards, though continuous monitoring is essential to prevent issues like the growth of P. mendocina.

​Project Impact:
- ​The project has garnered significant attention, including local media coverage, recognition in sustainability programs, and international interest (e.g., visits from the Technical University of Munich).
- ​It has fostered collaboration among different city departments and led to a follow-up project, COOLYMP

​An important lesson learned and with that also a recommendation for other projects, was the importance of integrating sustainable water management practices into the planning of Blue-Green-Infrastructure and urban planning in general, to ensure resilience against climate challenges:

- ​Encouraging the use of rainwater for irrigating public and private green spaces, combined with infiltration to replenish groundwater, mimicking the natural water balance of unbuilt areas. Storage solutions can include rain barrels, cisterns, underground tanks, ponds, or integrated water landscapes to maximize utility.

​- Green urban measures require significant water, necessitating strategic rainwater management for sustainable irrigation. During prolonged dry periods, alternative urban water resources (e.g., drainage water, underground streams, greywater) should be explored to reduce reliance on drinking water.

- ​Water features like fountains use less water than irrigation, requiring city-wide planning to balance available water resources with the needs of blue-green infrastructure. A usage-oriented approach to urban water resources, prioritizing high-quality drinking water for human consumption, is essential for sustainable water management.

​Besides an emphasis on the need to take into consideration sustainable water management for blue- and green infrastructure, the key recommendation formulated in the project was that cities must consider climate-adapted buildings in every urban and spatial planning project, starting with the municipality and possibly its subsidiaries. The city would thus serve as a role model for the population. Consequently, climate-adapted buildings could also be considered in private construction projects as a second step (possibly mandatory in the building code).