Stormwater Improvements to Public Parking Lot on Terry Estate Drive

This is a grant project in partnership with the Land of Sky Regional Council of Governments. The total project budget is $127,995. The town is only responsible for $51,198 over a period of two years. This funding is made possible by the stormwater utility fee. The balance is paid for by the North Carolina Department of Water Quality. 

The project will remove 23 pounds of nitrogen, 1.9 pounds of phosphorus and 339 pounds of soil and sedimentation each year. 

The project is part of the Upper Swannanoa River Watershed Management Plan. This new bioretention system will treat one acre of urban stormwater runoff at the Town of Black Mountain's Public Works and the public parking area on Terry Estates. The site is directly adjacent to an impaired section of the Swannanoa River, which will benefit from the pollutant reduction provided by bioretention cells in the public parking area along Terry Estate Drive and behind the public works building. 

The parking lot retrofit will consist of multiple new green spaces, increasing infiltration and treatment of stormwater from the parking lot. The lot will be redesigned. Safety conditions will also be improved, thanks to large biocells separating the parking lot from the street and creating a clear entrance. 

The rooftop runoff will be directed to a linear bioswale behind the public works building. It will utilize steep slope techniques to build treatment into the existing slope to minimize impacts within the sanitary sewer maintenance easement. The bioswale will be planted with riparian vegetation, and future work will focus on streambank stabilization and additional riparian restoration once the stormwater control measures are implemented.

1.0 BIORETENTION CELL AND PARKING LOT RETROFIT PLAN
1.2 ROOF DRAINAGE RAIN GARDEN PLAN (002)