Create obstacles to attenuate water speed, volume, and sediment flows

Options

  • ...with speed humps, large softscape areas, bioswales, rain gardens, or other features that slow and spread water out.
  • ...with floodplain benches that allow silt to deposit with the slowing and spreading of water.
  • ...through detention (green roofs, temporary storage, tanks, detention ponds, cisterns, trenches) or retention (retention ponds, wet ponds) that attenuate the release of water to the storm sewer.

Case Study

SWA transformed a former golf course into a series of five retention ponds, designed to hold 100 million gallons of floodwater each. By keeping rain out of the local bayous during heavy precipitation events, Exploration Green acts as a natural sponge, helping to reduce the chances of catastrophic system failure. Even when partially complete, it helped save as many as 150 homes during Hurricane Harvey.

Case Study for 3.3.2

Explore more tactics and resources in the Limit Exposure to Flash Floods strategy.