Collaboration with HCFCD Enhances Mosquito Control, Dragonfly and Butterfly Habitat Volunteers with NRG Energy, working with Houston Wilderness, Trees for Houston and Harris County Precinct 4, spent several hours May 17 planting the native coastal prairie grasses and wildflowers that will help transform a seven-acre Harris County Flood Control District stormwater detention basin near Telge and Spring Cypress roads into a haven for monarch butterflies and mosquito-eating dragonflies.

Armed with buckets and shovels, volunteers with NRG Energy planted more than 20 native species – including milkweed, swamp sunflower, big bluestem and gamagrass – that serve to restore the native coastal prairie habitat on which Houston originally was built.

Located in the Little Cypress Creek watershed, the basin was constructed by Harris County Engineering Department as stormwater mitigation for an adjacent road expansion project. Precinct 4 Commissioner R. Jack Cagle requested that the basin emphasize dragonfly habitat to provide natural mosquito control, and the Flood Control District worked with Harris County Engineering to design the wetland habitat features to accomplish this goal. The Flood Control District planted 14 native wetland vegetation species in late April that will also help filter and clean the stormwater that flows through the basin facility. Harris County Precinct 4’s Biological Control Initiative will install additional vegetation for mosquito control – including a native carnivorous plant, the floating bladderwort – at a later date.

In addition to the dragonfly-friendly wetland vegetation, the Flood Control District and Houston Wilderness coordinated with the volunteers to install native prairie vegetation in a one-acre area along the bottom of the basin, using a grant that Houston Wilderness received for its Monarch Flyway Strategy. Houston Wilderness provided 500 one-gallon native prairie grasses and wildflowers from Houston Audubon, plus approximately 30 pounds of native seeds, to attract the monarch butterfly, which is Texas’ official state insect. The prairie vegetation also provides habitat for numerous insects that will boost the dragonflies’ diet.

Through Houston Wilderness, NRG Energy agreed to provide volunteers to install the prairie plants, with shovels and gloves supplied by Trees for Houston. The basin, HCFCD Unit L500-12-00-00, will be maintained in the future by the Flood Control District. Stormwater detention basins reduce flooding risks and damages during heavy rain events by safely storing excess stormwater and slowly releasing it back to the bayou when the threat of flooding has passed.