Developers of an 85-mile, 230-kV transmission line in California's San Joaquin Valley said the project has moved one step closer to happening.
The San Luis Transmission Project is intended to provide electricity needed for the delivery of federal water supplies to Central Valley and Bay Area residents, businesses and farms.
The project's developers — the Western Area Power Administration, San Luis & Delta-Mendota Water Authority, the U.S. Bureau of Reclamation and Duke-American Transmission Co. — said Jan. 31 that they will negotiate an agreement that would provide the terms and conditions for construction of the line and associated substations.
If all goes well, construction on the project could start in the spring of 2021 and the line could be in-service in the summer of 2023, said Lisa Meiman, a spokeswoman with the Western Area Power Administration, or WAPA.
The project would run from WAPA's substation in Tracy to the San Luis, O'Neill and Dos Amigos substations in the Los Banos area. The route would parallel existing transmission facilities through nonirrigated ranch land, the developers said in a news release.

WAPA, the lead federal agency for the project, first considered it after receiving a transmission service request from the Bureau of Reclamation in 2010 for transmission capacity to serve load at the San Luis Unit of the Central Valley Project, Meiman said. That project provides water to the Central Valley and Sacramento and Bay areas.
The Bureau of Reclamation asked that WAPA develop a new transmission service arrangement to replace a contract with Pacific Gas and Electric Co. that expired in 2016. At roughly the same time, private transmission developer Duke-American Transmission filed a transmission service request to WAPA for capacity along the same path as the planned San Luis project, Meiman said.
"It made sense to combine the two requests into one project that would meet everyone's needs," the WAPA spokeswoman said in an email.
Along with providing long-term cost certainty for water customers, the project also will help enhance transmission system reliability and support renewable energy development in the area, the developers said.
The transmission line will have 600 MW of capacity, 400 MW of which will be used by water customers. The remainder will be made available to area utilities and renewable energy developers. The project is fully permitted and in the construction design phase. Duke-American Transmission, a partnership of Duke Energy Corp. and American Transmission Co. LLC, will soon begin marketing the additional capacity, the developers said.
Details of the project have changed over the years; in 2016, it included about 65 miles of 500-kV transmission line between new Tracy East and Los Banos West substations.
But Meiman said that after completing studies and an analysis of the project, the partners agreed that a 230-kV option was an economically viable solution that would meet the needs of the Bureau of Reclamation and Duke-American Transmission.
WAPA still plans to build an additional seven miles of 70-kV line between the San Luis and O'Neill substations, Meiman said. Discussions are ongoing, and other options listed in the final environmental impact statement for the project still may be pursued in the future, she added.
