Wilson Engineering has extensive experience with creating and upgrading lift station designs across Washington State. Below is a sampling of our recently completed projects.
BOULEVARD PARK SEWER UPGRADES, CITY OF BELLINGHAM, WA
Provided engineering, surveying, and construction management services for a new 8-inch HDPE gravity sewer line through Boulevard Park, grease interceptor, 6-feet diameter Flygt fiberglass package lift station, full SCADA Integration, and 2-inch HDPE forcemain over a railway crossing. Package fiberglass lift station included two Flygt grinder pumps, float and transducer level control, and separate valve vault. Each pump is capable of delivering 40 GPM at 175 TDH. The project included work in contaminated soils which required a less obtrusive design and planning for removal and disposal of soils and groundwater.
LIFT STATION NO. 10 RELOCATION OPTIONS ANALYSIS, CITY OF BLAINE, WA
Evaluation and alternatives analysis for relocating existing lift station with limited access and pump issues. Performed topographic and boundary survey. Evaluation considered path forward for City project and as a joint project with potential large private development nearby. Also evaluated and designed new pumps to replace outdated pumps. Preliminary site plans, cost estimates, and technical memo crafted with analysis of options.
UW FRIDAY HARBOR LABS LIFT STATIONS NOS. 1 AND 2 RECONSTRUCTION, SAN JUAN COUNTY, WA
Provided survey, permitting and engineering Design Phase services for rebuilding two (2) University of Washington Friday Harbor Laboratories sewer lift stations. Survey included topographic survey and 3D scan of existing structures. Design included pump options analysis, modifying dry well and wet well, odor control, new submersible pumps, new controls, new generator, flow metering, new discharge pipe valving, bypass pumping ports, new force main piping and other site improvements within approximately 30 feet of marine shore. Lift stations are owned by UW and operated by the Town.
SEWER LIFT STATION NO. 2 REBUILD, TOWN OF FRIDAY HARBOR, WA
Provided survey and engineering for pre-design and design phase services for upgrades to sewer lift station #2. Survey included boundary and topo services. Pre-design included operational alternatives and pump options analysis. Design included rebuilding existing station, abandoning wet well, converting dry well to wet well, odor control, new submersible pumps, new controls and wooden enclosure, flow metering, new discharge pipe valving, bypass pumping ports, new force main (approx. 800 LF); and other site improvements, including stormwater drainage and yard hydrant.
SEWER LIFT STATION NOS. 2 AND 3 REBUILD, CITY OF FERNDALE, WA
The City of Ferndale’s lift station Nos. 2 and 3 were existing wet pit/dry pit type sewer pump stations, each of which consisted of a 25’ x 25’ masonry block pump building constructed over a cylindrical concrete wet well and dry pit pump room. While each station is plumbed for three pumps, there were only two pumps in each. Originally constructed in the early 1970s, the stations were in desperate need of both structural and equipment upgrades to increase their reliability and pumping capacity for 20-year buildout projections. PS #2 is located immediately adjacent to the Nooksack River and has historically been threatened during flood events. The existing masonry block buildings had issues with their heating and ventilation, roof and skylights, and cross-connection control with their potable water systems. Both stations were unmetered.
Each station was refitted as a triplex pump station utilizing submersible-grade Flygt pumps installed in the dry pit pump room. The new pumps are controlled by variable frequency drives (VFD) to provide City staff with the maximum amount of flexibility in matching pumping capacity to actual flows. The wet wells were drained, resealed, repaired and Raven coated, and all pump control instrumentation was replaced. Each station was equipped with independent roof-mounted exhaust fans for both the wet-side and dry-side of the station. These exhaust fans are controlled through independent VFD controllers and capable of up to 20 air changes per hour (ACH) on the wet site and 10 ACH on the dry side, eliminating the need for auxiliary ventilation during confined space entry events. The building was also updated to include new heaters, a new air-gap water system for wash down, overhead crane facilities, new doors and ventilation louvers, and new membrane roofs and skylights. Because of space constraints within the masonry structures, new emergency backup generators were installed outside the station in weatherproof enclosures and equipped with propane backup fuel systems. At the PS #2 site, the generator, propane storage tank and all of the pump control and telemetry cabinets are set above the 100-year flood elevation to allow for normal operation of the station during flood events.
During construction, each station required a temporary bypass pumping system to allow for the complete shutdown of the station. The project plans and specifications detailed bypass flows and discharge heads for these temporary systems as well as schematics for their implementation. The project was funded directly by the City of Ferndale, and Wilson Engineering assisted with managing the cultural resources review, preparation of the SEPA checklist and the Shoreline Permit Application.
LAKE SAMISH LIFT STATION NO. 4 REBUILD, SAMISH WATER DISTRICT, WA
Lake Samish lift station #4 was a 38-year old, dualpurpose dry-pit sewer lift station which provided both influent pumping from the District’s Lake Samish collection system to their lagoon treatment system and effluent pumping from the lagoon discharge to the District’s Burlington forcemain. Because of its dual roll, the station was one of the District’s most critical facilities and it was the last of the District’s original lift stations to be rebuilt. In the interest of constructability, the decision was made to “divide and conquer”, splitting the facility into two separate duplex submersible stations – each with full redundancy and each with individual controls.
The new effluent lift station was constructed adjacent to the old station while that station remained online. Once the new effluent station was functional, the original lift station was decommissioned and dismantled. The dry-pit was abandoned in place, and the original influent wet well was repurposed as a duplex depth of submersible station. The influent station is located ~110LF from Friday Creek and high groundwater levels, coupled with the existing wet well (~30 ft.), made re-sealing and Raven coating the old wet well challenging. The effluent system required a gravity bypass during construction, and the influent lift station required a full pump bypass while the new influent station was rebuilt. The temporary pumping system effectively bypassed all of the wastewater flowing from the collection system around the lake for twelve weeks during the 20152016 winter season.
Additional improvements at the site include a new dual flowmeter vault, upgraded telemetry panels, a new generator shelter to house the District’s two portable trailer-mounted generators, a new sampling building, a new flow-splitter vault for the lagoon treatment plant, and miscellaneous access road and site improvements. Close coordination and planning with District staff helped tailor the facility to the specific operational needs of the District.
Wilson Engineering was responsible for securing and administering the funding for the project, which was obtained through the WA Ecology SRF Loan Program. The environmental review and permitting process included a wetlands delineation, a wildlife and fisheries habitat review, a cultural resources review, NEPA and SEPA determinations, and a Skagit County building permit for the generator shelter. We provided all of the project administration for the loan including documentation review for certified payroll, American Iron and Steel Act compliance, pay requests and quarterly reports.
Wilson Engineering also provided bidding and construction phase services for the project which was deemed substantially complete in March, 2016.
ROEDER LIFT STATION, CITY OF BELLINGHAM, WA
Grading, stormwater conveyance and design for a new sewer lift station facility. Provided permit assistance. Developed TESC and traffic control plans for site improvements. Project included restoration design of 2,000 ft. of roadway.
WATERFRONT REDEVELOPMENT LIFT STATION, CITY OF BELLINGHAM, WA
Master planning, multi-phase demand forecasting, design and construction document preparation for new sewer lift station to serve the redevelopment of the former GP site at the Bellingham waterfront. The 800 GPM duplex station featured a 10’ diameter, 20’ deep wet well, and the project included on-the-fly conversion to comply with federal steel funding requirements.
