CALFED Staff Report: Summary Review of Prior Delta Conveyance Reports

Over the past 40 years, state, federal, and local agencies, as well as academics have conducted numerous studies about the best way to move water through or around the Delta.

For this summary report, CALFED staff reviewed more than 100 reports — 30 of which specifically focused on various conveyance options—that dealt with Delta water conveyance and potential effects on water quality and ecosystem health and resilience.

Based on a review of these reports, it appears that most focus on the amount of water than can be moved and for what cost, but little work has been done to evaluate the effects on the Delta environment or the impacts of climate change and sea level rise.

We note, however, that several studies now underway are addressing these issues.

General conclusions based on this review suggest:

1. The operational criteria of a conveyance system is critical to determining if it will meet the environmental, water quality, and water supply reliability needs of the state.
2. Based on the reports we reviewed, none of the conveyance options stand out as a clear choice capable of fully meeting all the performance standards laid out by the Task Force. Some conveyance options do well in some areas, but not in others; some conveyance options do moderately well across all areas.
3. Few of the existing reports include operational criteria or specifically integrate much of the new and relevant scientific data about the Delta ecosystem.
4. Cost estimates developed were for the conceptual designs for particular studies. Most of the reports did not include cost estimates for operation, maintenance and mitigation. Cost estimates presented here are not current and are not comparable among reports.