An Additional 391 Billion Gallons of Water from the Delta Isn't "More Water"?

A week ago, Tom Birmingham, the general manager of the Westlands Water District, wrote an op-ed in the Sacramento Bee about the Bay Delta Conservation Plan, which stated,

“The public agencies that depend on this water system are not trying to take more water out of the Delta. We are trying to secure the same amount of water as we used to have and that has been promised to us under law.”

Mr. Birmingham’s definition of “not trying to take more water out of the Delta” would make George Orwell proud because, in fact, BDCP is proposing to take a lot more water from the Delta, more than they used to have, and more than is promised to them under law. 

As the chart below shows, under the water contractors’ proposal for BDCP, long term average water exports from the Delta by the CVP and SWP (part of it through a peripheral canal) would be nearly 6 million acre feet per year.

That’s a lot more water than what the CVP and SWP have historically exported from the Delta.  From 1980-2000, the average level of water exports from the Delta was 4.9 million acre feet.   With current protections for salmon and other endangered species in place, on average the Central Valley Project and State Water Project can export approximately 4.9 million acre feet of water per year out of the Delta.  Of course, if that’s the average, in wetter years they can export a lot more; we saw this in 2011, when even with protections for listed species the projects exported more than 6.5 million acre feet of water, the highest ever levels of water exports from of the Delta.  Thus, even with protections for salmon and endangered species, water exports are approximately equal to the long term average.  Today, the export contractors are receiving, as Mr. Birmingham puts it “the same amount of water as we used to have.”

Admittedly, several decades ago, the water allocation for the 600 farmers served by Westlands was typically 100%,  But back then, the 19 million people served by the Metropolitan Water District of Southern California took a lot less water from the Delta.  For instance, the initial 2011 allocation for Metropolitan is more than 1.146 million acre feet, and this amount is likely to increase substantially if 2011 is an average or wet year; however Metropolitan's 1996 allocation was just over 738,000 acre feet. I’m guessing that Metropolitan does not want to have “the same amount of water as we used to have,” as it would be a lot less than it receives today. 

So the latest proposal is for BDCP to take about 391 billion gallons a year (1.2 million acre feet of water) more from the Delta.   That’s a nearly 20% increase over current pumping levels – or what Mr. Birmingham calls “not trying to take more water out of the Delta.” 

Heck, even the flawed BDCP effects analysis admits that BDCP will “[i]ncrease total amount of water exports” (of course, they describe increased water exports as a conservation measure).  It seems that the contractors would like to return to the unsustainable level of water exports in the 2000s, when massive increases in Delta exports led to the collapse of delta smelt and other fisheries in the Delta.  I don’t begrudge the water contractors advocating for their own interests, but the fact that their interests are narrower than the public interest is precisely why they should not be permittees and should not be given a privileged role in implementing BDCP (as my colleague Barry Nelson wrote recently). 

Finally, there’s the question of what “has been promised to us under law.”  Westlands Water District has a contract for up to 1.15 million acre feet.  The key point there is that their contract, like the contracts for other CVP and SWP contractors, is for “up to” a maximum amount, with no liability if the CVP and SWP deliver less. The Westlands contract is very explicit that they are unlikely to receive that amount of water in most years.  The U.S. hasn’t breached its contract with Westlands, because Westlands wasn’t promised under law more than they are getting today. 

The reality is that water supplies in the Bay-Delta watershed are massively oversubscribed, with more water rights than there is water. In addition, in 2010 the State Water Resources Control Board concluded that, “The best available science suggests that current flows are insufficient to protect public trust resources,” and the Board recommended providing additional flows beyond the existing protections for salmon and other endangered species. 

Maybe it’s time for an honest conversation about what the purpose of BDCP really is: is it to significantly increase water exports from the Delta, or is it to increase the physical reliability of exports?  In light of the scientific evidence that current environmental flows are inadequate, focusing on the physical reliability of the system, rather than significantly increasing exports, seems more likely to succeed; together with investments in local and regional water supplies like water recycling, improved efficiency, and stormwater capture, that BDCP project could reduce reliance on water exports from the Delta and help California achieve a 21st century water policy.