The Sacramento Municipal Utility District is in the process of replacing a vintage 60-year-old substation with a $76 million upgrade that will serve midtown and downtown Sacramento.
Construction on the “Station E Substation” project is slated to begin this year and be complete by 2020. The project is designed to increase reliability and provide room to grow by accommodating increased demand.
Mike Deis, SMUD Director of Substations, Telecommunications and Metering, noted that land use planning and the associated growth decisions in the City of Sacramento are made by the Sacramento City Council. SMUD is responsible for serving the electrical demand associated with these decisions.
He said that the new Station E will serve the existing electrical load for the midtown and downtown areas. In addition, the new substation will also serve electrical load from the proposed significant rail yard development approved by the city.
The renovation of the substation will mark the utility’s first major substation upgrade since the 230-kV/69-kV Cordova Substation project located in Rancho Cordova that was completed in 2011.
As for any lessons learned from prior SMUD substation projects that were applied to the utility’s planning related to Station E, due to internal resource constraints, SMUD decided to construct the proposed Station E Substation by contract, while reserving the relay systems and SCADA testing for SMUD technicians. Contractor work will be reviewed by SMUD substation field personnel throughout the construction period.
SMUD utilized a request for proposals process to select the best value contractor to perform the construction. The evaluation included company and employee experience, proposed work plan and schedule, safety record and bid prices.
The project will replace the North City Substation, which is located immediately north of the property where Station E will be built. Station E will be interconnected with the existing overhead and underground transmission lines.
The land itself has been the cause of unforeseen delays as unexpected “burn waste” was discovered in 2015, two years after the utility purchased the land. To satisfy the utility’s goal of “leaving it better than we found it,” it will be spending an additional $13 million to clean up and properly prep the site for the new substation.
Prior to the sale, there were no public records indicating the presence of contamination even though it was adjacent to former landfill sites. SMUD commissioned a records search and a soils investigation which revealed an expected amount of contamination and construction debris but the burn waste was an unpleasant surprise.
To mitigate the effects of the compromised earth, SMUD has been working with county and state agencies to monitor the site condition by utilizing gas and water monitoring wells along the edges of the property. SMUD with the approval of the county and state has prepared a Soils Management plan to safely remove and transfer the soil to an approved landfill this summer.