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A Tale of Two Peripheral Canals. Or is it Three?

Barry Nelson

Posted January 8, 2009

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On Tuesday, the Sacramento Bee reported that The Nature Conservancy has conditionally endorsed a Peripheral Canal. News about the canal always travels fast. It's one of the most controversial projects in the contentious history of California water. 

The canal is designed to divert water from the Sacramento River, just south of the state capital, and divert it around the Sacramento-San Joaquin Delta to the enormous state and federal water pumps on the Delta's southern edge.  A previous proposal for the canal was rejected by California voters in 1982.  Margins in Northern California, driven by fears of thirsty Central Valley and Southern California water users, reached historic levels.  For example, 97 percent of Marin County voters pulled the lever against the canal.  For the next 25 years, the canal was ignored.  It became a third rail of California water policy. 

So what's changed to revive this debate?  Two things.  First, our understanding of the risks facing the Delta has changed.  Second, the canal is now more mirage than reality - more a concept than a concrete proposal.  Let's take these changes one at a time.   

Since 1982, remarkably little analysis or critical thinking has been applied to the Peripheral Canal concept.  As we learned more about changes in the Delta, the estuary's environment, climate change, water quality, alternative water supplies and more, no one analyzed how a canal would perform.   Little thought was given regarding why one would want to build a canal in the first place. 

This changed in 2007, when the Public Policy Institute of California released an influential report called "Envisioning Futures for the Sacramento-San Joaquin Delta". That report built on work done by U.C. Davis professor Jeff Mount, which concluded that there is a 2/3 probability of a catastrophic failure of Delta levees by 2050.  These risks are increasing over time, driven by ongoing land subsidence, inadequate levee maintenance, increasing earthquake risk and ongoing sea level rise.  The failure of levees on a dozen Delta islands would be a sobering event for hundreds of thousands of Delta residents, for water users South of the Delta, and for the environment.  PPIC suggested that a canal could be needed, not to increase water diversions, but rather to decrease the risk of a long-term shut down in Delta pumping as a result of levee failures.  This effort helped shape the Delta Vision Task Force's work on a comprehensive Delta plan. 

Second, today, there is no single canal proposal.  In fact, there is a remarkable diversity of ideas about a canal.  On the one hand, PPIC suggested that a canal could help reduce the risks posed by earthquakes and sea level rise.  In its final Strategic Plan  the Delta Vision Task Force agreed in concept, and called for strong new protections for the estuary and a new governance entity to ensure that a canal would be operated in a responsible manner.  Neither PPIC nor Delta Vision anticipated that a canal would produce much, if any, new water supply.  In fact, both suggested that a reduction in diversions might be needed.  They envisioned a canal designed to increase reliability, not supply, with major new environmental protections.  This is the kind of canal the Nature Conservancy has in mind.

On the other hand, last April, the Department of Water Resources released its own preliminary analysis of a canal.  The project analyzed by DWR was very different from that envisioned by PPIC and Delta Vision.  It did not include new standards to protect the Delta.  In fact, it relied on weakening and violating existing environmental standards. It would, according to DWR, lead to a dramatic increase in pumping.  This version of the project would cause major impacts to the Delta environment, water quality and Delta agriculture.  It would drain upstream reservoirs, leaving little or no cold water to meet the needs of spawning salmon.   This Peripheral Canal could lead to extinctions and the permanent closure of California's salmon fishery. 

These very different versions of the Peripheral Canal are just the tip of the iceberg.  Some have proposed that the "canal" should actually be a pipeline. Others have advocated a thousand-foot wide unlined canal built below sea level on subsided Delta islands.  Still others have suggested an alignment on the West side of the Delta, with a massive tunnel under the Western Delta to deliver water to the pumps.  Some have argued for "dual conveyance" - pumping through both a new canal and the existing intakes in the southern Delta.  Others insist on "full isolation."  Yet another proposal calls for armoring levees and separating Delta channels.  Delta Vision has called for a new agency to regulate a canal.  That proposal, however, is opposed by water users south of the Delta. 

Finally, after years of study and negotiations, EBMUD is currently building a (much smaller) canal around the Delta - called the Freeport Project.  In this case, the hard work paid off.  As unlikely as it seems, no one sued to stop EBMUD's project. 

In short, today, the Peripheral Canal is in the eye of the beholder.  Different canal proposals would have dramatically different implications in terms of cost, yield, benefits and impacts.  Nearly every stakeholder group could find in this list a version of the canal to oppose.

Given this tremendous uncertainty, it's not a surprise that the debate about the "Peripheral Canal" is often unproductive.  Without specific projects and careful analysis, this debate is often founded in hunches, history and near-religious faith.  Moving this discussion in a more productive direction will require three things - all of which are clearly outlined in the Delta Vision Strategic Plan.

First, we need clarity regarding the purpose of a change in the Delta conveyance system.  A canal designed to increase reliability and help restore ecosystem health would look very different from one designed to increase diversions.  These different projects would have different costs, impacts and benefits.  Specifically, water users South of the Delta should abandon the outdated assumption that a canal would automatically result in more water pumped from the Delta.  And California must make a dramatic investment in the "virtual river" - consisting of conservation, water recycling, urban stormwater capture and groundwater management.  These tools can help California meet its future water needs without more diversions from damaged ecosystems like the Delta. 

Second, careful scientific analysis must address the unanswered questions regarding Delta conveyance identified by the Delta Vision Task Force.  The Task Force concluded that a meaningful, final decision on conveyance is not possible until we answer these tough questions.  How much water would be diverted?  How would the project affect the Delta environment, water quality and salmon runs?  How would the canal's massive fish screens - which would be the world's largest - perform?  What new environmental standards would be put in place?  Would those standards include new protections called for by Delta Vision?  How would the facility fit into a strategy to restore ecosystem health and protect Delta residents and infrastructure?   These answers matter, particularly for a facility that could cost $20 billion and take 20 years to build.  Water users, regulators, environmentalists, fishermen, the Delta community and others can't judge a canal accurately without answers to these questions.  The Bay-Delta Conservation Plan  process, which is currently studying a canal, has not yet indicated if or how it will address these unanswered questions or incorporate key Delta Vision recommendations.  

 Third, the legislature must reform the agencies that manage the Delta, as recommended by the Task Force, with particular attention to reforming the regulation of the state and federal water projects.  Those projects have, in recent years, been operated with little regard to the needs of the Delta environment or the requirements of state and federal law.  That's why a federal judge stepped in, as a result of a lawsuit brought by NRDC, ordering the projects to comply with the ESA.  In another lawsuit, a state judge has ruled that the projects are violating California's ESA.  There are other violations as well.  Governance reform is essential to reestablishing trust that any Delta facility would be operated responsibly. 

The Delta Vision Task Force's Strategic Plan includes a detailed framework in each of these three areas.  The Task Force, however, has no implementation authority.  It is now up to the Governor, the legislature, state and federal agencies, and stakeholders to determine if this promising plan will be implemented or if it will simply gather dust. 

No one defends the status quo in the Delta.  The current levees are inadequate.  Urban development in the Delta is putting more and more people at risk of flooding. The Delta ecosystem is crashing, in large part because of excessive water diversions.  That's the devil we know.  On the other hand, we know remarkably little about a Peripheral Canal. No one believes that a canal alone could solve all of the Delta's problems.  Most importantly, to date, no one has produced a detailed, credible proposal that meets the test laid out by the Delta Vision Task Force. 

The quickest road to failure in the Delta would be a premature fight over an ill-defined Peripheral Canal.  Such a debate would be more faith-based than fact-driven and would inevitably lead to gridlock.  We've been here before. 

The past several decades are littered with efforts that failed to resolve the issues in the Delta.  Our new understanding of the Delta, however, shows that the stakes are higher this time.  Extinction is permanent.  As is sea level rise.  And a massive levee failure event could unalterably change the Delta and threaten thousands of residents.  If the Delta Vision effort fails, we may not have another chance.  

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Dan BacherJan 12 2009 06:02 PM

Barry has written a very interesting and well-thought out article with a lot of complexity and nuance, although I don't share his hope of the Delta Vision Process helping to resolve the Delta's
problems. The key point that he makes is that there are a number of different peripheral canal concepts - each report or agency advocating for the canal seems to have a different view of what it would look like and what purpose it would fulfill. That's why breaking ground on a peripheral canal, as the Governor's Delta Vision Committee proposes, is so dangerous and illogical. How do you break ground on a concept? It can't be done - and the Governor and his advisers are deluded if they thinks they can do it.

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