CCWRD PROJECT NUMBER 19104 – MOAPA VALLEY LEWIS LIFT STATION AND FORCE MAIN
This project includes the following:
- Removal of existing Moapa Valley Lewis Lift Station and Force Main (Lewis LS#25)
- Removal of existing temporary Lewis Lift Station (LS#25A)
- Design of a new lift station on CCWRD-owned parcel
- Design of a new primary and a redundant force main
- Design of a waterline to serve the domestic needs of the existing operations building
- Design of new communication conduits for future CCWRD use.
Lewis LS#25 is located at the east end of Lewis Avenue in Moapa Valley and currently consists of a lift station and dry well, existing temporary lift station, existing 10-inch force main, abandoned 6-inch force main, and existing temporary above-ground 3-inch potable waterline. Lewis LS#25 was nearing the end of its productive life and needed replacement of the lift station and wet well, redundant force mains, and a permanent underground potable waterline.
This project faces many unique challenges including coordinating with National Park Service (NPS) to renew an existing 40-foot easement from the NPS along Lewis Avenue to construct, operate, and maintain an existing underground sewer force main that had expired. An additional 50-foot easement from NPS was required for the existing 10-inch and new force mains, waterline, and fiber optic conduits.
Another challenge is to maintain the existing dirt access road along the Lewis alignment between the right-of-way and existing treatment plant during construction since it serves as the only route to the treatment plant and a private residence.
WATER POLLUTION CONTROL FACILITY – BIOLOGICAL NUTRIENT REMOVAL FACILITY REHABILITATION
GCW is providing design services for multiple projects at the City of Las Vegas Water Pollution Control Facility including the following work:
- Replace 8 failing 20-inch RAS system isolation plug valves and actuators.
- Assess and design pipe support system modifications at 10 locations.
- Replace 60 aged and failing variable frequency motor controllers (VFDs)
- Replace existing exterior lighting with LED lighting.
- Replace an HVAC cooling tower waterline and add a maintenance platform.
- Replace Plants 3 and 4 thickener drives and assess the overall condition.
- Revise sludge crossover piping and pumping system from parallel to series operation.
- Modify Plants 5 and 6 thickeners by converting parallel to series operation.
- Replace two bulk polymer storage tanks and associated piping in the dewatering area.
- Replace BNR influent pump station discharge header and knife gate valves.
- Rehabilitate sludge thickener mechanisms at Plants 3-4 and 5-6.
- Add two new sludge thickener pumping stations.
- Replace four double-disc sludge pumps.
Work also includes miscellaneous site-civil improvements, sedimentation basin ducking skimmer rehabilitation, addition of fiberglass reinforced plastic (FRP) stair towers to access each of the four BNR basins, and rehabilitation of the BNR basin drain pump station.
BERMUDA PHASE II SEWER AND LARSON WATERLINE
This project includes the final design of approximately 7,550 lf of 21-inch and 27-inch diameter gravity sewer in Via Centro, Larson Lane, Bermuda Road, and Volunteer Boulevard, and 1,900 lf of 12-inch diameter waterline in Larson Lane. The installation method of pipeline consisted of both open-cut and tunneling methods. The design also required the reconnection of existing sewers and service laterals, bypass pumping, traffic control, street reconstruction, combination air valves, and blow-off assemblies.
The project had an accelerated schedule that required completion of final contract documents in two months. Due to the fast-paced nature of the design, constant communication was required with multiple interdisciplinary teams including water, sewer, roadway, and survey. The design also required coordination with a private developer whose site is adjacent to the proposed sewer line.
CCWRD PROJECT NUMBER 725 – SOUTHWEST INTERCEPTOR
This project included the final design for approximately 21,000 lf of new sanitary sewer line ranging from 21-inch to 42-inch diameter in the southwest part of the Las Vegas Valley. The project was part of a regional solution to capacity deficiencies observed both in the southwest area and downstream at the Tropicana and Flamingo interceptors crossing Las Vegas Boulevard. The design significantly reduced the required improvements for the Tropicana and Flamingo interceptors by routing a majority of flow from the Southwest Valley area to the Paradise-Whitney Interceptor (PWI) sewer.
The proposed alignment included the following roadway segments:
- Windmill Lane – Rainbow Boulevard to Arville Street
- Arville Street – Windmill Lane to Wigwam Avenue
- Wigwam Avenue – Arville Street to Valley View Boulevard
The following challenges were successfully resolved:
- Structural support of the existing facilities.
- Maintenance of traffic, construction zone space requirements, and phasing.
- Scouring for Rainbow Boulevard interceptor to determine effects of removing flow.
- Encroachment permitting through BLM, NDOT, UPRR, and Clark County was required.
- Multiple dedicated easements were needed.
- Three crossings under the existing SNWA 84-inch waterline.
- Extensive public outreach to address impacts to the residents and business owners.
- Open-cut and trenchless construction methods.
TOWNSITE PHASE 1 – WATER & SEWER UTILITIES DESIGN CONTRACT
This project included final design for the replacement of existing water and sewer infrastructure for Townsite, a neighborhood in the City of Henderson (COH) that was established in the 1940s.
The existing water system was mainly comprised of cast iron pipe, ranging from 2-inch to 24-inch diameter. The existing sewer was mainly comprised of vitrified clay pipe (VCP) ranging from 6-inch to 15-inch diameter. The existing water and sewer service laterals are generally located in private backyards connecting to the public mains in alley ways. COH had determined that the existing water and sewer infrastructure has reached its design life.
Phase 1 included the installation of approximately 10,250 lf of 8-inch water line and 11,800 lf of sanitary sewer line ranging from 8-inch to 15-inch diameter.
APEX SURFACE WATER SYSTEM PHASE 2B PUMP STATION AND TANK SITES
This project includes the final design of a new water pump station, water transmission pipeline, and two 1.5 million gallon (MG) water storage tanks in the Apex Industrial Center located in North Las Vegas. The City of North Las Vegas (CNLV) and investment entities entered a reimbursement agreement in 2018 to design and construct the waterlines, water storage tanks, and water pump stations of the project. This project is Phase 2 of the infrastructure project to provide and water to the Apex Industrial Center.
The new water pump station is located at Apex Phase 1, Site 3, which is currently under construction. The site includes two 1.25 MG water storage tanks and a chemical building for chlorination as part of Phase 1. The GCW-designed water pump station consists of four 2,000 GPM pumps with 400 Hp motors. Two pumps will be initially installed with the remaining two pumps installed in the future. The pump station will be designed and manufactured by Engineered Fluid Inc. (EFI). The project also includes a water surge tank and emergency generator at Site 3.
The pump station will deliver water through a 24-inch diameter DIP water transmission main to Site 4 of the Apex system. The alignment of the waterline follows SR 604 from the Site 3 pump station to Nadine Peterson Boulevard. The route continues northwest along Nadine Peterson Boulevard across the utility corridor to Solo Mountain. The route runs northeast on the west side of the utility corridor to the north side of Solo Mountain and then west to the Site 4 tank site located on the northwest side of Solo Mountain. The length of the water transmission main is approximately 34,000 lf.
Site 4 will include two 1.5 MG AWWA steel water storage tanks, site fencing, a chlorination building, and room for a future water booster pump station. One tank will be initially constructed with the second tank built in the future.
This project faces many unique challenges including a compressed schedule and dynamic design process to meet the client needs. The water booster pump station is a high head (pressure) pump station requiring that GCW perform detailed analysis system appurtenances to ensure compatibility with higher than typical pressures.
VIA NOBILA AND VIA INSPIRADA 2630 AND 2760 PZ WATERLINES
This project consisted of the final design for approximately 5,930 lf of new 24-inch diameter DIP waterline in Via Inspirada between Via Da Vinci and Via Nobila and Via Nobila from Via Inspirada to Via Centro. The second source of water within the 2760 pressure zone for this developing area will be provided by this work.
Design included valve outlets at the major intersections, fire hydrants, and a 66-inch casing sleeve for the future 48-inch (2630 PZ) transmission line at Via Inspirada. Additional efforts include design and calculations for restrained joint design, sizing of combination air valves, and proper fittings and appurtenances necessary to provide a complete waterline. Design also included cathodic protection details and two 4-inch fiber optic conduits with pull boxes for future City of Henderson use.
This project was a fast-track project with accelerated design turnarounds, and is one of many concurrent designs within the same area which required constant communication with all stakeholders to limit to amount of potential construction conflicts.
C1461 MISCELLANEOUS MAIN REPLACEMENT, THE DALES SUBDIVISIONS
This project consisted of the final design for the replacement of all the water facilities in the Park Dale Subdivisions bordered by Lamb Boulevard on the west, Vegas Valley Drive on the north, Mountain Vista Street on the east, and Desert Inn on the south and included the following improvements:
- Approximately 26,400 lf of potable water pipeline ranging from 6-inch to 12-inch diameter.
- Approximately 50 inline valves.
- Approximately 46 fire hydrants.
- Approximately 640 small services (2-inch and smaller).
- Approximately 6 large services (greater than 2-inch) with backflow installation.
- Three connections to large diameter water pipelines at the following intersections:
- Lamb Boulevard/Vegas Valley Drive intersection (48-inch waterline)
- Lamb Boulevard/Ridgedale Avenue intersection (48-inch waterline)
- Lamb Boulevard/Desert Inn Road intersection (36/48-inch waterline)
- Removal/abandonment of existing water facilities.
GCW also provided topographic/aerial mapping, right-of-way and easement research, utility agency coordination, and a construction sequencing plan to limit the disruption of service. Groundwater pumping was necessary due to the high groundwater.
HARMON AVENUE/VALLEY VIEW BOULEVARD/UPRR GRADE SEPARATION 84-INCH WATERLINE RELOCATION
This project consisted of preparing a feasibility study/final design for grade-separated extension of Harmon Avenue and Valley View Boulevard across UPRR tracks. The project required the relocation of an existing SNWA 84-inch waterline. GCW prepared the final design and separate bid package for the relocation of the existing SNWA 84-inch waterline that was required to be relocated due to the proposed grade separation. The contract documents included SNWA specifications on shutdown, contractor qualifications, and corrosion recommendations. The relocation design included the replacement of 789 lf of existing 84-inch reinforced concrete pipe (RCP) located in Valley View Boulevard, north of Harmon Avenue, with 980 lf of 84-inch cement mortar-lined and coated (CML&C) steel pipe.
A detailed construction phasing plan was developed and consisted of the following:
- Installation of new pipe outside of Valley View Boulevard including four bends, combination air valve manhole assembly, low point drain assembly, two manhole pipe access assemblies, four construction pipe access assemblies
- Shut down and drain existing 84-inch RCP.
- Removal of approximately 48 lf of RCP at each end to allow CML&C steel pipe connection, installation of the CML&C steel pipe connection pieces including bend, closure connection with butt straps, connection of the RCP to CML&C pipe, and thrust block.
- Removal/disposal of remaining 84-inch RCP.