It would seem logical that lowering the capacity of the Delta tunnel(s) would result in the remaining capacity being used more intensively. That was how it worked when DWR briefly switched to a staged, single-tunnel plan for the WaterFix in 2017, as well as other alternatives with lower capacity.
Instead, the draft EIR for the single-tunnel DCP states that the tunnel will be used much less than the WaterFix twin-tunnels. In fact, the operation modeling shows zero diversions through the tunnel most of the time. In the DCP, the tunnel only makes up 13.5% of projected Delta water exports, compared to 50% of total Delta water exports in the WaterFix.
Is this low-utilization rate of the DCP believable? Will the state spend $20 billion on the most expensive water infrastructure project in history and not operate it most of the time (or as Osha Meserve said, why buy a Maserati and only drive 10 miles per hour)?
That is indeed the official plan as described in chapter 3 in the EIR, and subsequently used in all the analytical chapters that follow.
However, the Draft EIR itself contradicts these operations in chapter 2: Purpose and Objectives and in and Appendix 3a where it interprets and elaborates on the purpose to screen out all alternatives. The project objective is to achieve the following 4 purposes in a cost-effective manner.
1. Climate resiliency
2. Seismic resiliency
3. Water Supply for State Water Project
4. Operational Flexibility
The problem is that achieving 3 out of the 4 project purposes, as described in the alternatives analysis in Appendix 3A, require shifting diversions from the south Delta to the north Delta intakes and through the tunnel. In other words, 3/4 of the stated project goals are in conflict with the project description and EIR modeling which focuses exclusively on a low-utilization scenario.
Goal 1, Climate resiliency: Appendix 3A states that only tunnel alternatives satisfy climate resiliency because they can divert from the north when the south is too salty. Stunningly, this flat out ignores the water quality commitments and limited north delta diversion in the actual project description. (In Appendix 4A, the EIR models a climate change scenario, and finds that there are actually fewer days on the calendar that the tunnel can be used under climate change. Thus the incremental water supply benefit decreases as climate change accelerates, in contrast to Appendix 3A that assumes higher tunnel use under climate change when screening out other alternatives.)
Goal 2, Seismic resiliency: Appendix 3A assumes that if brackish water fills the Delta in a seismic-induced mega-flood, then the north Delta intakes and tunnel will be used intensively in place of the south Delta pumps which would be unavailable for months due to bad water quality. This assumption is inconsistent with the project description which commits to operating the project to support Delta water quality objectives and limits use of the north Delta intakes. The EIR provides no explanation of why the environmental restrictions and water quality objectives in the Delta would be waived in such a scenario where the Delta communities and environment are experiencing an emergency, and it provides no modeling of the environmental impacts of operations in such a case.
Goal 4, Operational flexibility: Appendix 3A describes this as a certain kind of flexibility - shifting south Delta diversions to the north Delta. Again, directly in conflict with the project description which does not include such flexibility or any analysis of the environmental impacts of this alternative operating scenario.
The final part of the project goal, which is the only one not in the Appendix 3A screening criteria, is to achieve the goals in a cost-effective way. The EIR is completely silent on cost-effectiveness, but this is another goal that would seem to be in conflict with the low-utilization of the tunnel in the project description.
So back to my original question: Is DWR being truthful? Will they really keep the north Delta intakes off and the tunnels empty most of the time?
The alternatives analysis and how it interprets the project goals show they are not really committed to the low-utilization project description. When this is combined with the lack of economic and financial feasibility analysis, I believe the project description lacks credibility.
While it is tempting to rate the EIR project description as "Pants on Fire" on the Truth-o-Meter, I'll keep my rating at "lacks credibility" or "inadequate support" as I am sure there are honest folks who worked on this draft EIR who truly believe in their $20 billion mostly-empty tunnel proposal.
In summary, the DCP EIR has many problems, and I have only touched on one of them here. As a result, I believe this single-tunnel proposal will fail like the twin-tunnel proposals that preceded it.