The Otay River Pump Station (ORPS), which pumps 7–9 MGD of raw sewage to the South Bay Water Reclamation Facility for water recovery, had a problem in the 50’ long x 10’ wide x 30’ deep wet well. A floating blanket of grease and debris, sometimes as thick as 4’, would occur on a regular basis.
The City of San Diego had been contracting two vacuum trucks to clean out the station every 3–4 months at a cost of approximately $50,000–$100,000 per year. Based on previous experience with Vaughan chopper pumps, the city turned once again to Vaughan Company for a more cost-effective solution.
Vaughan chopper pumps are ideal for use in pump stations and lift stations as conditioning pumps (patented with additional patents pending). When used as a conditioning pump, a submersible Vaughan chopper pump is fitted with a nozzle to provide high-velocity mixing. The purpose of the conditioning pump is to recirculate and chop the contents of the wet well.
For ORPS, an 8” submersible chopper pump was selected with a 25 hp, 1,200 rpm motor with mixing nozzle and portable stand. In 18 months of conditioning pump use, the wet well has not required vacuum cleaning. Based on the cost of the pump and installation, the pump paid for itself in 2 1/2 months of use. WW
The Vaughan Company is exhibiting at WEFTEC.19, booth 1017. To learn more, visit www.chopperpumps.com.