A roof journey

In today’s city environments, extreme weather conditions are a fact of life. Amsterdam, Mumbai, Nairobi or Sydney… climate change issues need to be tackled all around the world. In the last couple of decades, Amsterdam has dealt with larger amounts of rainwater, severe heat stress and a decreased biodiversity. In order to strengthen urban resilience to climate change, bluegreen (BG) roofs are increasingly being introduced. BG roofs place an additional water layer underneath the green layer. The idea is that these roofs reduce runoff after rainfall by retaining precipitation and mitigate heat stress, caused by increased evapotranspiration (the sum of evaporation from the land surface and transpiration from plants) and a higher albedo effect (the ability of surfaces to reflect sunlight).

Living laboratory
With RESILIO, a project which lasted from November 2018 to April
2022, Amsterdam created a living laboratory: 10,000 m² of BG roofs
on existing social housing and privately owned real estate. The latter
took place through a municipal grant scheme. The roofs have a ‘Smart
Flow Control’ which anticipates heavy rain or drought, releasing or
retaining water accordingly. The roofs are connected in a network,
enabling remote regulation of rooftop water levels, based on weather
forecasts and watermanagement settings.
Ambitious ‘ecosystem’
RESILIO was developed in an Amsterdam ‘ecosystem’ which has
experimented with BG roof solutions since 2013. Many of the
partners involved in the project knew each other and their ambitions
beforehand. Pilots and experiments, such as the first Polder roof
and Project Smart Roof 2.0 (see chapter 2), had already brought the
concept of micro watermanagement to life before the start of RESILIO.
Considerable progress
The RESILIO partnership, consisting of a quadruple collaboration
between public authorities, knowledge institutes, the private sector
and the voluntary sector, booked considerable progress in the
adoption of governance strategies, cost-benefit analyses (CBA) and
business case approaches, community involvement and engagement,
public procurement, data collection and usage, as well as new Internet
of Things (IoT) technology in a Decision Support System (DSS).
This report will guide you through the project and inform you
about the lessons learned.

Image credits

Icon image: Resilio - banner

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