In general, MID and TID certainly support the State Water Resources Control Board’s pursuit of better water quality in the Delta and a healthy salmon fishery. However, we don’t agree that increased river flows are the sole solution to fixing these needs. And we certainly don’t agree that the San Joaquin River tributaries, such as the Tuolumne River, should be responsible for fixing these problems, especially when one considers MID and TID are not beneficiaries of water managed by state and federal agencies in the Delta.

Coming off the driest five-year period on record in the state, and after three years since the State Water Resources Control Board’s Draft Substitute Environmental Document (SED) in support of Phase 1 of the Bay-Delta Plan was released, the State Water Board’s updated SED:

  • Ignores our communities’ pleas to include dry-year relief
  • Fails to eliminate the months of February and June from its objectives, which can be harmful for salmon
  • Fails to adequately acknowledge the relationship between surface water and groundwater

Elements of a solution

While MID and TID feel that the State Board hasn’t improved its proposal in the past three years, MID and TID have invested more than $25 million to develop the best available science on the Tuolumne River. This science has allowed us to develop non-flow solutions that could be implemented now to benefit the River. Here’s a few:

  • Implement a predation suppression program on the Tuolumne. More than 90 percent of outmigrating juvenile salmon are consumed by predatory fish before they reach the San Joaquin River.
  • Implement river and habitat improvements on the Tuolumne, such as gravel improvements, water hyacinth removal efforts and riparian vegetation expansion.
  • Restructure existing river operations. Science shows that improvements to salmon and rainbow trout populations can be significantly improved by modifying the timing and duration of existing river flow requirements.

Important questions

Among all the known water management tools, regulators like the State Water Board consistently focus on flow-centric approaches. One problem with this approach is that additional flows should be utilized as a last resort because water is a scarce resource and the impacts will be devastating.

In looking at potential additional unimpaired flows as a possible mandate of Tuolumne River water, MID and TID customers deserve to know from the State Water Board, among other things:

  • Where will these instream flows go?  How far will they go? Will they make it as far as The Golden Gate? (previous work associated with MID and TID submitted to the State Water Board shows that even 40 percent unimpaired flows February through June on the San Joaquin tributaries in less than average water years won’t even make it as far as the Bay.)
  • Will these flows get diverted from the San Joaquin River before making it to the Delta in certain years?
  • How does this play into the Governor’s WaterFix project aka the twin tunnels, especially when one considers that WaterFix plans to divert Sacramento River water around the Delta?
  • Are these desired unimpaired flows from the San Joaquin tributaries meant to prevent ocean water from intruding further into the Delta so WaterFix can be constructed on the backs of a regulatory taking of water from San Joaquin tributaries?


“I think we really agree you can’t just throw water at something and get a proportional positive response. You can’t just throw more water at the river and expect that the environment is going to get better.”
State Water Board member Steven Moore, testifying before Senate Rules Committee, June 8, 2016