The starting point for GrowGreen was the involvement of stakeholders in the design of the pilots using participatory planning processes. The three cities each constructed NbS projects:
• Manchester - a new amenity park with three interconnected areas: woodland; meadow and a community plaza garden with a flexible event space and community growing spaces.
• Valencia - a Sustainable Forest, a green-blue corridor along an urban street, a vertical ecosystem, a green roof and community initiatives e.g. a growing project, meeting space and biodiversity app.
• Wroclaw - internal courtyards within residential housing blocks and a green street in one of the city’s most densely populated districts.
Detailed monitoring and evaluation plans were developed covering a range of climatic, environmental and social indicators. Baseline diagnostics looked at climate, air and water quality, health, water management, noise, green space and soil contamination, as well as the social and economics. The focus was to improve climate and water resilience and also to look at the co-benefits of engaging with the local community, stakeholder participation and influencing city governance and the future of NbS in urban environments. The evidence based outcomes demonstrate:
• Water management and flood risk: NbS features may differ in type, size and construction but hydrological processes are similar. The outcomes of monitoring show the ability of NbS features to reduce urban runoff with a higher than average performance figures (99-100%).
• Heat stress: the baseline data shows the cities are all dealing with an increase of temperature. The heat intensity outcomes conclude NbS can reduce the occurrence of heat stress and provides evapotranspiration.
• CO2 savings: NbS on buildings can have an immediate impact by using plants and organic materials with immediate benefits on the thermal behaviour of the building. Carbon sequestration in trees and vegetation has a significant role.
• Biodiversity: all the demonstration areas show significant biodiversity uplift as a result of the introduction of trees, shrubs and herbaceous plants and the protection of mature trees.
• Water quality: NbS features have the ability to ameliorate and reduce contaminated runoff.
• Social and participatory research: the process and provision of NbS benefits from a participatory planning approach, engaging the local community creates a sense of ownership. There are tangible impacts on health and wellbeing.
• Financial benefits: the financial implications of NbS are challenging to quantify and need longitudinal studies.
• Management and maintenance - SuDs need a bespoke maintenance schedule with the need for those responsible for maintenance have an understanding of the issues.
The project results are available in accordance with Horizon 2020 Open Research Data Pilot (ORDP) as follows:
• Manchester – research results www.manchesterclimateready.com/.
• Valencia -
https://opendata-innova.vlci.valencia.es/(opens in new window)• Wroclaw -
https://www.wroclaw.pl/open-data/(opens in new window)Going forward, the pilots will all be monitored for the next 5 years (up to 2027) with the results made available as above.
