Stormwater Control Retrofits | Town of Cary

Gradient designs stormwater control measure retrofits that enhance local drainage, reduce erosion, and improve water quality within North Carolina communities.

Vickie Drive SCM Retrofit

Gradient designed an SCM retrofit in Cary, North Carolina, near the intersection of Vickie Drive and Greenwood Circle. The retrofit SCM captured run-off from an existing curb-gutter and flume.

The project included a greenway re-alignment and improvements to the curb-gutter and concrete flume configuration. The SCM is a boulder step-pool basin (consisting of four steps) with a stalite sub-drainage layer and underdrain system.

The purpose of the retrofit project is to improve local drainage efficiency, minimize erosion, and improve water quality into the Swift Creek watershed. The construction started in January 2024 and was successfully completed in August. Gradient also provided limited construction administration support.

Urban Park SCM Retrofit

Gradient designed a series of SCM retrofits in the Town of Cary Urban Park. The retrofit SCMs captured run-off from an existing park, parking areas, road areas, and flumes.

The project included improvements to curb-gutter and concrete flume configurations. The SCMs included a sod-covered bio-retention basin, as well as a landscaped bio-retention basin, both with stalite sub-drainage layers and underdrain systems.

A third area was included that utilized ponding in a natural area of cypress trees. The purpose of the retrofit project is to improve local drainage efficiency, minimize erosion within the park, and improve water quality into the Walnut Creek watershed. The project is currently on hold awaiting grant funding.