Location: Walkersville, MD
Application: Detention
Product Used: 5’-6” DoubleTrap
Total Water Stored: 153,592 cf | 3.5 acre-ft
Number of Basins: 1
Number of Pieces: 496
Foundation: Stone
Owner: Frederick County Public Schools
Consulting Engineer: ADTEK Engineers, Inc.
General Contractor: Keller Construction Management
Rock Creek School is a public school located in Frederick, MD that provides special education programs. Due to the increasing number of enrollments, the school is now being relocated to the Walkersville Middle School (WMS) grounds in Walkersville, MD. The new school building will be constructed behind the Middle School and provide a larger facility to welcome more students. With the site alterations and increase of impermeable surface, a stormwater system was needed to manage stormwater runoff.
ADTEK Engineers, Inc. partnered with StormTrap to design an underground system to store stormwater and control the rate and volume of runoff leaving the site, in accordance with the City’s stormwater regulations. The area available for a detention system was limited due to existing infrastructure and the new building structural elements that will be installed on the site. After close evaluation, the engineering team at ADTEK decided that the parking lot area of the new school would be the best location for the system, where before was the athletic field of the WMS.
Taking into consideration the spatial limitations, a 5’-6’’ DoubleTrap basin, built with 496 modular pieces, was designed for this site. The system allowed for meeting the required storage volume of 153,592 cf, while also minimizing excavation. “StormTrap was a great fit for this project due to its adaptable/adjustable height,” affirmed Jacob Glotzbach, E.I.T., Civil Engineer at ADTEK.
Other products were also considered for the project, such as corrugated steel pipe systems; however, those don’t offer the same service life as products made of high-strength precast concrete (up to 100 years*). “Steel systems do not have a long enough service life for schools within Frederick County, and concrete, in this case, was preferred,” stated Glotzbach.
The system was successfully installed, waterproofed and backfilled in nine days. The new Rock Creek School is scheduled to open in the fall of 2021.
Reference
* Frank, Dean A. “Precast Advantage.” National Precast Concrete Association, 29 May 2010, precast.org/2010/05/precast-advantage/.
