In 2008 the city launched a Green Roof Pilot Project on eight city building roofs as part of their Municipal Climate Protection Programme. Each roof featured different plants, growing material and green roof techniques. They proved so effective as a storm water management tool they were included in the Municipal Adaptation Plan.
In 2010 the city released its Guideline for Green Roof Habitats to help residents who were already starting their own projects. The Creating Learning Space Programme brought schools into the project. Plants covered roofs and walkways and were restricted to vegetation that could be found within 50 kilometres of the school.
The city's Green Roof project has been lauded internationally for its biodiversity.