This is Storm Water Solutions 2020 Top Project.
Location: Wilson, North Carolina
Cost: $1.135 million
Size: 15,930 square foot system
Owner: City of Wilson, North Carolina
Designer: Bartlett Engineering & Surveying
Contractor: Fred Smith Co.
Wilson, North Carolina, had old and undersized storm water infrastructure in the downtown area, which was prone to flooding. During heavy rain events, existing storm water infrastructure could not hold excess water, which would back up and flow out of the local catch basins.
The Whirligig Station parking lot was identified as the best location for installing a storm water management system. The goal of this project was to alleviate pressure in the current system to provide flood relief and to improve the quality of storm water.
The $1.135 million project installed a large underground sand-filter system capable of storing approximately 116,000 cubic feet of water and complied with the North Carolina Department of Environmental Quality requirements.
The Whirligig Station parking lot improvement project had a short construction timeframe. Everything had to be finalized by the middle of July due to other development deadlines and start dates. For frequent flooding issues, the city considered upgrading the current system, but the cost was extremely high.
The StormTrap system was selected for the project due to its capacity to store a large quantity of water in a small footprint, its water pretreatment feature and more. The team also faced the following: poor soil conditions, excessive rainfall during construction and high groundwater. During installation, they discovered that the entire system needed to be lowered 6 inches due to an elevation issue with the existing drain system, but the issue was resolved. The system was installed in six days.