Cosumnes Power Plant

CLIENT: Sacramento Municipal Utility District
LOCATION: Sacramento, CA

The Cosumnes Power Plant (CPP) is located on a 30-acre site a half-mile south of the now closed Rancho Seco Plant in southeastern Sacramento County. SMUD owns and maintains 2,480 acres surrounding the site that includes a decommissioned nuclear power plant, a photovoltaic generating facility, and the Rancho Seco Recreational Area. A sizable buffer zone and the re-use of existing facilities made the site an attractive place to build a state-of-the-art thermal plant.

The CEC granted a license to construct on Sept. 9, 2003 and site construction began shortly thereafter. The Project will be completed in two phases of 500 megawatts each. SMUD brought 500 megawatts (Phase 1) online in 2006. The District will continue to study the expansion of up to 500 megawatts (Phase 2) and will make a recommendation at a later date to either implement or defer Phase 2 of the CPP project.

To bring natural gas to CPP, SMUD extended its existing 50-mile pipeline network from the Carson Ice Generation Plant another 26 miles to the CPP. The pipeline runs south from the Carson Ice-Gen Plant and then turns east to avoid heavily populated areas. Construction of the extended natural gas pipeline was completed in 2004.

SMUD contracted with IEC to provide Owner’s Engineering services. The work began as a small contract and quickly expanded into a multiple year commitment by SMUD for Project Coordination and Owner’s Engineering services.

IEC provided the Licensing Project Manager, Environmental Specialist, Mechanical and Electrical Engineers, and a variety of subcontractor specialties such as geotechnical services and pipeline inspection services. IEC engineers managed installation of the electrical and control systems, reviewed design, and corrected errors while supervising electrical installation. IEC managed subcontractors, provided technical guidance and leadership to craft labor, managed project priorities and schedule, and coordinated work with other disciplines. Our personnel worked with the plant quality control team to ensure compliance with the latest codes, specifi cations, permit conditions, and accepted practices, and assisted the startup lead contractor with commissioning activities throughout the facility as systems were brought on line.