Hazelwood West High School, located in north St. Louis County, serves approximately 2,400 students with approximately 300 faculty and staff. When the school was first constructed in 1969, it included an underground Smith & Loveless pump station that conveyed wastewater to the public sewer from its campus. The pump station consisted of a buried wet well connected to a buried pump vault. In late spring 2009, after nearly 40 years of faithful service, school officials determined that a new station was required.
The school implemented a best value approach to the project and turned to local design-build firm Haberberger for their experience. They evaluated three options: (1) replace all of the pumps and valves in the existing buried pit, along with associated electrical and control work; (2) abandon the dry pump pit and install submersible pumps into the existing wet well; and (3) install a EVERLAST™ Wet Well Mounted Station on top of the existing wet well. With input from the school’s staff and thorough assistance from S&L rep firm Municipal Equipment Co., the third option was selected because the above-grade concept demonstrated a more economical approach, not to mention the significantly safer and easier access to the pumps for inspection and O&M.
The cornerstone of the EVERLAST™ Wet Well Mounted Station concept is still the lowest proven cost of ownership throughout the life of the pump station. First and foremost this accomplished through the safe and simplified access with the complete lift station residing at ground-level. This alone eliminates confined space costs for routine inspection and maintenance. Additionally, installation is very simple, and can be achieved in typically less than day for complete start-up.
Several important attributes contribute to the lowest life-cycle costs: Durable, high-efficiency pumps – both in terms of motor and pumping efficiencies – draw less power than alternate pumping schemes while S&L Pump vertical pump construction design promote typical service life of 25+ years and the ease of routine maintenance. This includes exclusive Smith & Loveless traits like oversized stainless steel pump shafts (with a minimum of overhang), oversized bearings, bronze seal housing, premium efficiency motors with Class F insulation, and trimmed impellers inside the shrouds. Additionally, removing the entire rotating assembly is simplified; merely removing eight capscrews connecting the motor adapter to the volute facilitates full access to the volute and suction elbow. This gives the School the ability to perform virtually all pump maintenance and repairs onsite – if desired – without the use of outside contractors or expensive pump maintenance centers.
This robust pump construction and ease of maintenance contributes to capital and O&M costs remaining low throughout the long expected service life of the station. To illustrate the cost of ownership benefits, recent cost compilation studies demonstrate that for typical wastewater pumping conditions in the 4-inch to 8-inch category (flows of less than 1000 GPM per pump and 50,000 gallons per day), Smith & Loveless stations are proven to save 57% in maintenance and repair costs over duplex submersible arrangements. This difference factors costs generated from materials, in-house (staff) labor (time), and outside contractor labor. All told, this translates to thousands of dollars per individual pump station per year.
All parties moved quickly to get the project completed before school started in August. While the pump station was being fabricated and tested by S&L, Haberberger was busy completing a review of the flow data and conducting on-site work at the pump station site in preparation of the new pump station’s arrival. Hence, when the new pump station arrived on site, everything was ready so it could be immediately installed. The new pump station was set in place, the piping connections made, and electrical connections made. Municipal Equipment Co.’s local start-up technician was present immediately thereafter to test the new station and perform O&M training for the school personnel.
In summary, the new EVERLAST™ Wet Well Mounted Pump Station was in-place and running satisfactorily before the first day of school. The school district obtained a safer and more efficient pump station that will yield cost savings for decades to come. It’s been operating for approximately a year now, and the school’s maintenance staff is very pleased with its reliable performance and easy access. Maintenance staff can perform all inspections and maintenance at grade level without any confined space restrictions.
“The process offered innovation, cost benefits and energy-efficiency to the project,” writes Don Kettenbach of the Hazlewood School District. “The (pump station) that was installed is easy to maintain, aesthetically acceptable as well as compact and adapted well to the existing piping system.”
On Nov. 19, 2010, the Design-Build Institute of America’s Mid-America Section recognized the Hazlewood West School Pump Station Project at its annual Design-Build Awards Competition in Kansas City as an outstanding Water/Wastewater design build project in the Midwest.
Our appreciation goes to Danny Rowatt P.E., Municipal Equipment Co. and Haberberger Inc. for the primary information contained in this profile.