California Logistics Center Finds Stormwater Solution

The Rialto, Calififornia-based I-210 Logistics Center is part of a proposed master-planned project located on and around the Rialto Municipal Airport. The 1445 acre site is a premier West Rialto location, with high-profile corporate neighbors including Target, Under Armour, Black & Decker, Solo Cup and Kuehne + Nagel. The 718,000 square-foot (66,704.4 square meter) industrial distribution warehouse will house products until they are ready to be shipped to their final destinations across the country.
Upon completion, the Logistics Center will feature a cross-dock facility with 32 feet (9.75 meters) minimum warehouse clearance, 185 to 344 feet (56.39 to 104.85 meters) concrete truck courts, 112 dock loading doors, each 9 by 10 feet (2.74 by 3.05 meters) high, and 249 trailer parking spaces each measuring 10 by 53 feet (3.05 by 16.15 meters). Approximately 3380 square-feet (314.01 square meters) of the building will be dedicated to the office space.
THE CHALLENGE OF A DUAL-SYSTEM DESIGN
In addition to designing the facility, engineers from SB&O Inc. collaborated with EW Harmon Contracting, Inc. to design and install a stormwater detention and retention system to comply with water quality requirements as well as provide stormwater pre-treatment to the site.
Engineers determined that the most economically effective method of stormwater management would be to combine an underground network of chambers with a separate above-ground system consisting of retention/detention basins—a relatively new practice. A challenging aspect of the dual-system design was determining how the two systems would interact with each other, and how to keep siltation out of the underground system, into which water from the above-ground system migrates.
To mitigate water quality concerns, engineers chose to raise the inlets in the above-ground detention basins so that the silts had a chance to settle prior to flowing into the underground chamber system consisting of 726 units. Two CULTEC StormFilter® 330 units filter runoff before it enters a CULTEC Separator Row™. The StormFilter 330 is a chamber-shaped secondary filter which contains two removable pass-thru filters. Water passes thru the filter baffles and is captured or settles to the bottom of the unit. For maintenance, the StormFilter housing can be vacuumed out and the filter bags may be replaced or cleaned and reused.

Engineers determined that a combination of underground chambers and above-ground retention/detention basins would be the most economically effective method.
THE SEPARATOR ROW: A CLOSER LOOK
The Separator Row, comprised of a select row of underground chambers, is enveloped with No. 410™ filter fabric and sits on top of two layers of woven geotextile fabric. The Separator Row pre-treats runoff by capturing silts and fine particles in a row of chambers prior to runoff overflowing into the rest of the infiltration basin. To help maintain the stormwater system, debris can be easily vacuumed out using a water jet, which pushes water toward the catch basin and sump while removing waste.
The Recharger V8HD was selected for the Logistics Center because it both maximizes storage in a small footprint and satisfies the other design requirements of the site. The internal manifold feature available on the stormwater chamber allows for a more cost-effective and condensed bed size since a costly and time consuming custom pipe and fitting external manifold fabrication is not required. Smaller chamber-like “feed connectors” are inserted into side portals located on the sidewalls of the stormwater chambers to create the internal manifold. Installation is quick and efficient.
MEETING REGULATORY REQUIREMENTS
Regulatory bodies called for a stormwater solution that would mitigate the proposed flows to be equal to or less than the existing flows on site—particularly for higher-flow flood conditions. Moreover, to meet water quality regulations, a certain volume had to be retained onsite and infiltrated into the ground to accommodate lower-flow water quality requirements.
“Water flows into the above-ground detention/retention basins and fills about a foot deep before overflowing into the CULTEC chambers located underground,” says Don Brooks, engineer with SB&O Inc. “The two systems combined provide the detention and retention volumes required to meet the regulatory requirements of the county.”
Each Recharger V8HD chamber measures 32 inches (812.8 millimeters) high and 60 inches (1524 millimeters) wide and has a bare chamber capacity of 8.68 cubic feet (0.25 cubic meters) per linear foot. The bed of chambers provides the site with a total of 72,857 cubic feet (2063.08 cubic meters) of storage. In addition, the V8HD model is able to withstand traffic loading with minimal cover—a major site requirement since the chambers will largely be covered with parking areas. Further, there is no underground storm drain system to tie into, so the runoff outlets are located to the street surface. For this reason, the engineers were eager to keep the storage elevation as high as possible to direct the flow to the street.
A WINNING TEAM
“This was our first time working with CULTEC, and we look forward to teaming up with them again in the future,” recalls Brooks. “Their team was very responsive and helped us get the job done quickly and efficiently.”
Cultec introduced its Contactor® and Recharger® HDPE septic and stormwater chambers in 1986, which helped begin a revolution toward the use of plastic construction products. Since then, several product developments and strategic alliances have seen the chambers used as subsurface retention or detention systems and as replacements for ponds, concrete structures or pipe and stone installations. ■
For More Information

CULTEC’s technical staff offers free design assistance including preliminary calculations and job-specific CAD details. For more information about CULTEC stormwater management chambers and other products, call 203.775.4416 or visit www.cultec.com.