West Yost provided planning, design, and construction management for the Ophir Road Pump Station. This pump station constructed about a mile upstream and 210 feet above the Auburn Tunnel outlet, allows Placer County Water Agency (PCWA) to pump water from the tunnel for municipal and agricultural use. It is designed to pump 332 cfs of water through three distinct pump stations, housing 11 vertical turbine pumps ranging in size from 200- to 600-hp.
Two of these pump stations are built and the third will be constructed in the future. Other significant features of the project include a 1.25 MG concrete lined transfer basin, an intake screen facility, an energy dissipation structure, a medium voltage power distribution system, extensive site work, and piping systems ranging from 1-inch to 96-inches in diameter to serve the new facilities.
Unique features of the design and construction include:
- Pioneering methods for designing 32-inch diameter, 210 feet deep blind shafts in Granodiorite
- Construction of the pump station included excavation through fractured unstable rock and through solid hard rock
- Construction adjacent to a 100+ year old PG&E canal
- Environmental protection and coordination with regulatory agencies
- Open communications with stakeholders and local advisory council
- Assuring public safety and minimizing nuisances from blasting and other construction activities
- Architectural style and details that add character and reflect the area’s history
- Sustainable features built into the facility and site landscaping
The project includes the construction of a 75 feet by 148 feet pump station building housing three different pumping facilities. Two of the pump stations constructed as part of this project include six 600-hp vertical turbine pumps installed in 32-inch shafts drilled down 210 feet through solid rock to pump water from the existing Auburn Tunnel to the surface, and five 600-hp pumps to pump water from the pump station site to the Foothill Water Treatment Plant.
Multiple construction specialties were incorporated into the project requiring construction management and inspection for building systems and subtrades including: blasting, vertical drilling, rock anchors/rock bolts, reinforced concrete, structural steel, masonry, metal roofing system, stone and thin brick veneer, stucco, glazing, 12,000-volt, 4,160-volt, and low-voltage electrical equipment, PLC controls, SCADA, instrumentation, extensive mechanical work, a fire and security alarm system, and four types of HVAC systems serving areas with differing heating/cooling requirements. Extensive site work, paving and grading, security fencing, and landscaping was included. The project also included the rehabilitation of pumps and motor starters for an existing pump station that needed to be kept operational for seasonal water deliveries and emergency water conveyance.
The project has been designed and constructed with many elements that provide increased reliability and flexibility to PCWA’s water supply infrastructure. Of great importance to PCWA is that the structure and site work have been designed and built with architecture that conforms to the agricultural heritage of its location…We are extremely proud of this project and believe it is representative of an outstanding public works project.
Brian C. Martin, PE,Director of Technical Services, Placer County Water Agency
I believe this is by far the best project the Agency has had during my 22-year career at the Agency…The fact that there were no open issues of claims to deal with at the project completion speaks highly to the level of CM services West Yost furnished to the Agency.