By Kimberly Paggioli, P.E.
The population of Utah has been growing recently and this trend is projected to continue well into the future. More than 20 million people visit the popular ski resorts to enjoy what the state's license plates describe as the "Greatest Snow On Earth." But the local population is growing along with tourism, so local municipalities are taking a closer look at their current infrastructures.
The South Valley Sewer District (SVSD), which includes approximately the southern third of Salt Lake County, serves Bluffdale, Copperton, Draper, Herriman, Riverton, South Jordan and South Sandy. It is investing roughly $3 million in its infrastructure. District municipalities reportedly include more than 4,400 building lots that are not yet connected to the existing system. These lots will require more than 1½ million gallons per day (mgd) of additional capacity. The district has been experiencing rapid growth over the last several years, stressing its existing facilities.
To handle the growing loads in southern Salt Lake County, relief lines and new facilities, including a wastewater treatment plant, are being designed and constructed. Since March 2002, SVSD officials have been seeking approval for an ultra-filtration treatment plant to be located in Riverton that will enable them to keep pace and provide enough capacity for the next 10 to 15 years.
When it's completed, the Riverton facility will add 15 mgd to the district's treatment capacity, with potential for more upon future expansion. The sewer district will keep its 13.2 mgd at the existing South Valley Water Reclamation Facility (SVWRF), which is currently under expansion. When the SVWRF plant expansion is complete in two years, the SVSD will acquire an additional three mgd.
Additional piping networks are necessary to insure that sewage can be transported to the existing treatment facility until the new plant is complete. One of the most recent projects was the Jordan River Outfall Sewer. This new line's primary purpose was to mitigate the capacity problems with the existing 48-inch line that has been in operation since the early 1980s. "The (Jordan River) project included approximately 4,000 feet of 48-inch HOBAS pipe and 16 seven-foot manholes. It is one of the district's main outfall lines to the treatment facility and the district put the project out to bid in January of 2007," explained Michael H. Foerster, P.E., district engineer with SVSD.
Bowen, Collins & Associates of Draper, Utah, that specializes in providing water, wastewater, storm water, groundwater, civil engineering and environmental services to clients in the Intermountain West, was hired to design the outfall. Allied Construction and Development Inc. of Logan was awarded the bid to install the pipe.
Both direct bury and boring were included in the installation. HOBAS centrifugally cast, fiberglass-reinforced, polymer mortar (CCFRPM) pipe was specified. "The use of HOBAS pipe on this particular project was determined and required by the South Valley Sewer District. We had installed 24-inch HOBAS pipe on another project about 1 1/2 years earlier for Cottonwood Improvement District in Cottonwood Heights, Utah. The Jordan River Project was mostly direct bury with several installations of HOBAS through steel casings. On both occasions the pipe installed well and had no problems with visible deflection and joint leakage," said Bart LaMont, project manager, Allied Construction and Development.
