Green Roofs Reduce Flooding

Green roofs are a green infrastructure gi option that can be applied to virtually any rooftop given weight load capacity.

Green roofs reduce flooding.

They have become very popular across europe. A green roof can help prevent this by retaining water in the plants and growing medium thus slowing and reducing the amount of storm water entering the ecosystem and consequently reducing flooding and erosion. The saturated soil will slowly release water off the roof but the green roof slows the process down reducing the risk of a flash flood. A green roof can retain around 75 of the runoff in summer source.

As a result they have become popular across europe. To represent this many green roofs in our region are referred to as living roofs or eco roofs. Green roofs are covered with growing media and vegetation that enable rainfall infiltration and evapotranspiration of stored water. Green roofs reduce the volume of storm water runoff and filter the storm water runoff that does leave the roof.

Compared to other strategies green roofs are relatively low impact as they utilise existing space. In addition green roofs reduce the cooling and heating needs of buildings. Green roofs reduce the need for on site storm water management systems and according to seattle based magnusson klemencic associates under certain conditions can offset the cost of a green roof by 30 to 60. To mitigate the risk of flooding in urban areas a number of strategies have been proposed including roofs that are covered with vegetation to absorb rainwater.

Provide pollutant removal through uptake and filtering. The benefits of green roofs. Green roofs for stormwater management. Extend the life of the roof membrane.

Green roofs roofs that are covered with vegetation by their very nature absorb rainwater and help to mitigate flooding. However as part of a wider rainwater management scheme they can be a useful contribution. They reduce flooding erosion and artificial heating of water which helps preserve the ecological integrity of surrounding bodies of water. Besides reducing urban flooding green roofs also help reduce pollution.

Storm runoff typically picks up oil trash and other pollutants from roadways which then get pushed into sewers and waterways. And can be designed for public access. Green roofs alone would not prevent flooding. If green roofs reduce that runoff they contribute to cleaner creeks rivers and oceans.