Clark County Detention Center (CCDC) is located in Las Vegas, NV and serves as the city jail. A high volume of large debris in the waste water at CCDC must be macerated before being discharged into the City sewer. A design/build project was commissioned at CCDC to replace an existing macerator/pump system which was failing.
Jensen Engineered Systems (JES), a division of Jensen Precast, assisted the plumbing sub-contractor in the design of a grinder/pump station. The preliminary design called for a large, pour in place concrete structure. The challenge of building the structure was that it was located between two high-rise buildings in close proximity. Additional challenges: all mechanical equipment was to be located in a dry pit (no submersible motors), complete system redundancy and one station to both grind and pump waste water.
The last requirement would typically be solved by passing waste water through three independent structures: grinder vault, wet well, and then a dry pit pump vault. JES combined the first and third structure into one, “U” shaped design. By stacking two manhole bases on top of each other, JES was able to minimize the needed footprint, and provide the dry environment for the mechanical equipment. Complete redundancy was provided by utilizing a three-way plug valve with an electric actuator on the upper grinder deck. Once a week, the sewage flow is redirected to the alternate grinder. Alternating duplex pumps were also used. All plumbing of mechanical equipment took place at the Jensen Precast facility prior to delivery.