Location: Chapel Hill, NC
Application: Filtration – Sand Filter
Product used: 8′-0” DoubleTrap
Number of pieces: 194
Total water stored: 42,869 ft3
Filtration surface area: 930 ft2
Flow rate capacity: 930 gpm
Orange United Methodist Church (OUMC) is the oldest Methodist Church in Orange County, North Carolina and has been in existence for over 180 years. The church has grown exponentially in the last 10 years and needed to expand their buildings and parking lot to accommodate their growing congregation.
The church is in the early stages of the expansion project and has just completed the stormwater portion of the project. OUMC worked with Philip Post & Associates, the engineering company for the project, and chose StormTrap to design and manufacture the stormwater management system, which meets the water quality and attenuation requirements of the entire site. The DoubleTrap system was chosen for this project because of its ability to maximize the site’s storage volume while minimizing the footprint and overall costs.
“We have used other products in the past. Mostly, circular CMP pipes for storage,” stated Ernest Dodson, Project Engineer at Philip Post & Associates. “Because of the large volume of storage required for the current development at the church and to accommodate planned future development with limited footprint area, we determined that the StormTrap system provided the most efficient configuration.”
The StormTrap system is designed to allow the stormwater runoff to enter into the sediment chamber and flow over the weir wall into the sand filter chamber. The runoff infiltrates through the sand and then exits through the underdrain pipes. The treated runoff is then conveyed to the outlet control unit and sent downstream.
“We were able to provide the needed volume and the water quality feature (sand filter) for this project within the available space under a parking area. To achieve the same volume using circular products would have taken more than the available area with the required separation of the pipes and the volume lost in the haunches, etc. The vertical walls of the StormTrap units made the best use of the available area,” said Dodson.
The system consists of 194 pieces and the entire installation process took just 3 days including the setting of the StormTrap pieces and assembling the sand filter.
“StormTrap was very responsive and available throughout both the design and installation,” stated Dodson.