Raingarden Demonstration Project

The Harris County Flood Control District is exploring new low-impact ideas to lessen the burden on neighborhood storm sewer systems and reduce local street flooding. Raingardens – small, shallow, specially planted areas that collect and promote infiltration of rainwater – have been used successfully in other areas of the country to reduce flooding risks and improve stormwater quality.

In 2022, the Flood Control District is working to identify previously cleared buyout lots in multiple watersheds to test this new Green Stormwater Infrastructure (GSI) technology. The goal of the raingarden demonstration project is to monitor and document the effectiveness of raingardens in Harris County soils.

Raingardens are sized to serve small drainage areas, like residential lots, and are typically about 6 inches in depth. Depending upon design considerations, each raingarden may include an overflow connection to the existing neighborhood storm sewer or roadside ditch system. The Flood Control District will construct, plant and maintain the gardens, and collect data on their effectiveness in reducing runoff and street flooding.

Eventually, if raingardens prove successful in Harris County as a GSI tool for flood risk reduction, the Flood Control District is considering a program allowing neighborhoods and homeowner groups to install and maintain more raingardens on Flood Control buyout lots around Harris County.

Once final sites are identified, it is estimated that raingarden construction will take place in Winter 2022-23.