By: Lane Enterprises, Inc
The MAWC Sewer Site Campus Expansion is the first phase of a $6 million project to build a new garage and office structure to house sewer operations for the Municipal Authority of Westmoreland County, Pennsylvania.
The installation of nearly 2,000 feet of 120 inch diameter aluminized CSP to meet storm water detention requirements was part of the site work necessary for the construction of the 58,600 square-foot storage and business space located on 35 acres adjacent to the utility’s New Stanton, PA campus, which houses its water distribution administrative offices and storage garages. The building is expected to serve as the headquarters for its growing sewer business, which now has more than 26,000 customers.
Storage requirements were met by specifying fully perforated CSP so that the facility would function as an infiltration system, whereby the porous stone backfill envelope provides additional water storage that can drain into the ground and outlet through gravity drainage pipes simultaneously.
Specifications included wrapping the entire backfill envelope in a geotextile fabric to maintain separation from adjacent soils, sustaining the storage capacity over the service life of the system. The storage provided in the detention system is approximately 232,000 cubic feet.
All in all, specifying a CSP detention system for an agency accustomed to operating and maintaining underground facilities is a testimony to the performance and service life afforded by these CSP systems.