by Bill Argeros
Phoenix-based CSK Auto Inc. is the largest specialty retailer of automotive parts and accessories in the U.S. West. Since 1998, the company has experienced tremendous growth through a combination of acquisitions as well as store construction and expansion. Its headquarters include a warehouse that serves as a major distribution point shipping automotive products to over 1,300 retail auto parts stores in 22 states including Checker Auto Parts, Schuck’s Auto Supply, Kragen Auto Parts and Murray’s Discount Auto stores. As a result of the demand for products, expansion plans for the warehouse became a necessity.
As with all land development projects, stormwater management had to be addressed. According to EPA rules under the Clean Water Act, a certain percentage of stormwater runoff must be contained and treated onsite. There are several stormwater best management practice options including use of ponds or swales. These aboveground solutions, however, require a certain percentage of valuable land that could be used for further development. Due to land constraints of the site itself, selection of a stormwater system would need to increase retention of stormwater runoff while minimizing the amount of surface land sacrificed.
CULTEC Inc. provided a solution by installing a multi-level subsurface retention system able to store vast amounts of post-development stormwater runoff. The system also helped the owner manage the remainder of undeveloped land to maximize the building’s expansion, parking areas and access drives.
Engineers from Phoenix-based Evans Kuhn & Associates Inc. specified a CULTEC two-tiered underground system to capture, treat and retain runoff until it could be displaced. Tiered systems are designed to allow for a smaller footprint in restricted areas without sacrificing infiltration capabilities. The system included about 2,400 Recharger® 330 HD chambers constructed of high-density polyethylene (HDPE), set up to maintain a significant permanent pool of water between rain and snowfall events.
“Design flexibility of the chamber beds allowed configurations not possible with traditional underground retention storage methods such as concrete vaults or corrugated metal piping, which both require more maintenance and in some cases even lift stations,” said Todd Nedderman, the project’s civil engineer from Evans Kuhn & Associates. “Working on a previously developed site with limited space for expansion can be challenging to design both in terms of cost as well as the ability to provide enough land for adequate parking and access.”
The underground stormwater management system offered additional advantages including strength and durability. The chambers used in this application are designed for high-traffic settings and built to withstand the weight of 18-wheelers that visit the CSK Auto warehouse daily. They feature a built-in endwall for strength throughout the system, as well as a patented, overlapping rib connection that affords a stronger connection between chambers.
Conclusion
The CULTEC multi-tiered system installed at the CSK Auto warehouse site offered distinct advantages over other open retention/detention options by freeing up land and placing the system underground. And with a 10-year warranty, it’s guaranteed to effectively manage stormwater runoff on the site for many years to come.
About the Author: Bill Argeros is the Southwest director for CULTEC Inc. Based in Brookfield, CT, it specializes in subsurface retention/detention stormwater management systems and septic installations. A 15-year veteran of the stormwater management industry, Argeros has been with the company 12 years. Contact: 602-615-6586 or www.cultec.com
