Green Roof Absorb Rainwater

But too much of it especially in the city can lead to flooding causing sewers to overflow and carry pollutants and contaminants to nearby streams and waterways.

Green roof absorb rainwater.

A green roof absorbs rain water by the water buffering in the plants substrate and drainage layer. Green roof systems are one of the best ways to manage stormwater runoff by reducing and delaying. Extensive green roofs will capture and retain about 55 of the annual rainfall thereby reducing stormwater runoff to the storm drainage system in pennsylvania. Green roofs absorb rainwater and grow food.

Up to 75 of rainfall is absorbed by an extensive living roof and up to 90 is absorbed by an intensive green roof system. By using green roofs as rainwater capture areas the amount of collected water for reuse will be reduced already due to the absorbed amount of water in the system itself. It helps plants and food crops flourish and it keeps grasslands green and lush. This delays the discharge of rainwater to the sewage system purifies the rainwater and water also evaporates through the plants.

Keep in mind that this assessment only applies to the green roof footprint which is typically less than 90 of the building footprint not the whole parcel being developed. Green roofs absorb rainwater grow food. Excess water drips from the roof gradually so drains are not overwhelmed by a sudden deluge.