In a sharp rebuke of state plans for a massive water tunnel system in Northern California, federal environmental officials say that the project would violate pollution standards and could worsen conditions for imperiled fish species.

The comments by the regional office of the U.S. Environmental Protection Agency echo concerns that have dogged the proposal to change the way Northern California water supplies are sent to the San Joaquin Valley and Southern California.

They also underscore the difficulty the $25-billion project may have in getting the necessary environmental permits while also satisfying the water demands of the agencies that are to underwrite much of its cost.

In a letter accompanying 36 pages of formal comments posted online Thursday, regional EPA administrator Jared Blumenfeld outlines a number of problems with the project, which has been years in the planning.


The proposal calls for the construction of new intakes on the Sacramento River as it flows into the Sacramento-San Joaquin Delta, the hub of the state’s water system. The river water would be diverted into two 30-mile tunnels running beneath the delta to existing pumping plants that now pull supplies from the interior delta.

Although proponents say that the new diversion point will improve delta conditions and ease pumping restrictions, the EPA concluded that it “would contribute to increased and persistent violations of water quality standards in the Delta,” harming the supplies of local farmers and municipalities.

Operations “may contribute to declining populations of Delta smelt, Longfin smelt, green sturgeon and winter-run, spring-run, fall-run and late-fall run Chinook salmon,” the document states.

The agency questions whether the extensive habitat restoration that is part of the project will be as beneficial as projected and emphasizes the need for adequate freshwater flows.


The critical comments are a major reason state officials announced Wednesday that they were revising the project’s draft environmental review, signaling another delay in a planning process that has consistently fallen behind schedule.

A year ago, officials said a final decision on the proposal would be made in late 2014. But it will take months for the state and federal agencies involved in the project to address points raised in voluminous public comments, pushing a decision date well into next year.

bettina.boxall@latimes.com

Twitter: @boxall