Costly, painfully slow delta study only half finished

The Sacramento-San Joaquin Delta is a crucial part of California's complicated and crumbling water system.

It suffers from the fact that, over the decades, too many promises have been made for its water, so there's no way to deliver on them all during several years of drought.

So we end up where we are today, with feuding politicians holding the delta hostage and interested parties oversimplying the conflict as "farmers vs. fish" or big agriculture conservatives vs. liberal environmentalists.

Even a scientific study of the crisis has fallen victim to the political spin machine. The National Academy of Sciences has released the first part of a $1.5 million study on the science that has led federal wildlife agencies to limit pumping of agricultural water from the delta to restore threatened species.

The report was barely released before the sides began "interpreting" its core findings. Certain environmental groups claimed the science panel had validated the need for greatly reduced water pumping from the delta. Farm interests seized on parts of the report that questioned certain federal actions aimed at protecting fish.

A close reading of the study reveals that the National Academy's panel offered a much more nuanced bottom line. Overall, the panel found that most of the actions by federal agencies to reduce water diversions were "scientifically justified," based on the current understanding of this complex ecosystem.

But there's much more to the story than agricultural pumping, and that's what the second part of the study will determine. Unfortunately, it is taking much too long to resolve that second key issue.

We acknowledge that pumping has had a negative impact on threatened fish. But it's also clear that other stressors -- including invasive species and the treated sewage that cities around the delta are dumping into the estuary -- have played a role in reducing fish populations.

Unfortunately, federal and state authorities only want to limit farm pumping, while ignoring the other causes. It's much easier for them to dump the entire problem on agriculture than tell cities that they must find multi-million-dollar solutions to their sewage dumping.

The National Academy's panel noted in the report that a much more integrated analysis is needed to better understand this system. No surprise there.

Sen. Dianne Feinstein, who originally sought the study, and farm groups had hoped the panel would help them in their efforts to suspend two biological opinions that have restricted water diversions.

The National Academy panel will now complete the second part of its review, which is expected to take 20 months and cost another $750,000. That report will finally examine the array of factors -- not just water diversions -- that are harming the delta and complicating water shipments. It's amazing that isn't being looked at until now.