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FrankenDelta
The plethora of problems plaguing the Delta-a crashing ecosystem, crumbling levees, and politicians and a public who don't understand the landscape-have visions of a different, more sustainable Delta dancing in some scientists' heads. A large, open body of water resembling Chesapeake Bay. A Delta that is fresher in the spring and sometimes in the winter, and saltier in the fall. A Delta re-connected with flows from both of its rivers; one not treated as an isolated system but as the linchpin of a 60,000-square-mile watershed. Yet any discussion of a different Delta seems to lead to a discussion of a Delta circumvented by pipes, carrying freshwater flows around it.
If we decide to try to maintain some of the natural ecosystem while still providing water for urban and ag users, does that inevitably mean building the peripheral canal (dreaded by many enviros) or a version of the peripheral canal? Not necessarily, says UC Davis' Jeff Mount, one of the scientists sounding the loudest warning calls about the Delta. But, he says, if we intentionally breach some levees (ones likely to fail anyway) and let the Delta become more brackish, we would have to desalinize the water we're pumping south. How difficult would that be? The California Bay-Delta Authority's Joe Grindstaff, who has been involved in building brackish desal plants, says the cost is about $500 per acre-foot (vs. as much as $1,200 per acre-foot for ocean saltwater). "For urban Southern California, they would hate that, but it is not beyond the pale," says Grindstaff. "But for the farmers in the eastern part of the Delta and the Central Valley, that would kill farming. You could not do ag in this state at that price." Yet compared to the cost of continual levee reinforcement, desalination might be a bargain in the long run, says the Bay Institute's Marc Holmes. Grindstaff says there are other issues to be considered with desal-such as where the plant would be sited and the energy use that would be required. "It may be that we do want to do it, but it may be that there are other ways to control water quality in the Delta or to supply water when it is brackish. There may be ways around some of the challenges; we haven't looked at it enough."
One "other way" might be "dual conveyance," says Grindstaff, in which we continue to use the Delta for some pumping, but also use pipes to carry a certain baseline amount of water around the Delta. "It gives you some reliability in case of a massive earthquake, and it also improves water quality and keeps exporters interested in the Delta. I don't think a peripheral canal as originally envisioned is probably feasible-there's been a lot of development in the areas where it was intended to be built." The Central Delta Water Agency's Tom Zuckerman thinks any new pipes or canals are a bad idea. "Those 'dual conveyance' pipes are designed to carry about 4,000 cfs-it doesn't sound like a lot, but it's equivalent to about 75% of the Sacramento River's flow in dry years. It would be a huge increase in deliveries out of the Delta. Any isolated facility around the Delta would ensure [the Delta's] destruction over time."
Zuckerman thinks that instead of breaching levees in the western Delta, we should strengthen them to protect water quality and find ways to take less water out of the Delta. "As the saying goes, 'It's the water, stupid.' The more people want to increase exports, the less feasible it is to have a healthy Delta. We've proven that. We need to think about how to decrease exports to the point where the Delta can sustain itself." But the San Luis & Delta-Mendota Water Authority's Tupper Hull says recent science doesn't support Zuckerman's contention. "I think it's now becoming clear that the Delta ecosystem is very complex, and that the role of water exports appears to be relatively minor-if not nonexistent-in terms of impacting fish species and the like." And he doesn't think desal is the answer either. "We can make it more difficult and more costly to grow food in California. But we are not doing anything for the fish." Hull says his agency is trying to stay out of the intensively political debate about a new peripheral canal, but he does think a conversation about the canal would be more constructive than discussing exports.
For now, the pipe/canal plan may be moot. Mount points out that the CALFED Record of Decision has effectively kept everyone from discussing anything but the option of running water through the Delta. The ROD is scheduled to be reevaluated in 2007, but he thinks it is not too soon to start putting all ideas on the table. Assuming that such thorny, politically charged issues as new pipes and water treatment could be worked out-and that all stakeholders would agree that the Delta needs ecological rescue-what kind of restoration could be done? "People cling to some obscure and obsolete notion of the Delta," says Mount. "One hundred and fifty years ago, it was a 700,000-acre freshwater tidal marsh. Today it is something completely different. We don't even have a name for the kind of system it is today." There are no systems for us to really compare it to, he adds. But the Delta as we know it is "dead and gone, and there is no turning back. Now we are managing for something other than the Delta, whatever that is. Our problem is that we can't seem to figure out what we want it to be. 'Frankendelta'?" Mount and U.C. Davis' Peter Moyle have suggested trying to head off the next earthquake or flood at the pass by breaching some of the levees north and east of Antioch, which could result in a large body of open brackish water-a Chesapeake Baylike scenario.
The Bay Institute's Tina Swanson agrees with Moyle that "no matter what we do, we can never get back the natural historic Delta." But Swanson says S.F. Bay isn't Chesapeake Bay-and that there are lots of uncertainties as to how the Delta would react ecologically or hydrologically to attempts to make it resemble its East Coast sister. "We have a long history of physically manipulating the Delta, trying to make it better. But that doesn't work," warns Swanson. "We need to be very careful. On the other hand, it is absolutely clear that maintaining the status quo is positively unsustainable if our objective is going to be to balance the needs of the ecosystem with farming and water quality and supply." The levee-breaching idea makes Zuckerman nervous, too. "It's an unproven sort of concept. Once you start creating these open areas where there is lots of fetch and wind action, you can begin to lose islands successively. Why run the risk of losing the entire Delta?"
What should be done? Swanson says we need to regroup, reevaluate, and remember that two rivers drain into the Delta. By withdrawing less water from the beleaguered San Joaquin River- and thereby improving water quality-we could significantly improve Delta habitat, says Swanson. The goal, she explains, is to better manage the Delta for native species, a principle most scientists think leads to a more sustainable ecosystem.
Swanson points out that historically, the Delta was fresher in the spring and periodically in the winter (because there were less upstream dams capturing flows, and because less water was diverted from the Delta itself), and saltier in the fall. "One of the things we've done is increase flows through the summer and fall. The way we operate it now, we've significantly reduced within-year variability." That disruption of the natural hydrograph, says Swanson, is one of the factors she thinks has enabled non-natives to thrive and possibly decimate native fish and pelagic organisms. "Natives can tolerate episodic, disruptive events-they evolved in those conditions," she says. But non-natives are happier with the current, more static situation. Says Swanson, "It is becoming scientifically clear that the best thing you can do for aquatic ecosystems is to preserve key portions of the hydrograph-such as a snowmelt pulse and low flows [in water-scarce months]."
U.S. EPA's Bruce Herbold echoes Swanson's views about trying to restore a more natural hydrograph. He envisions "a future where saltwater comes in every summer and drives out introduced species, enabling native and long-established Estuary fish like striped bass to thrive.
Before we started tampering with the Delta, says Herbold, it was very much an "inland sea" that drained through a narrow gap in the Montezuma Hills. "It was like a bathtub with a small hole; it stayed fresh for a good part of the year," he explains. But Herbold recognizes that we aren't going to get back to that. "We're not going to move the city of Stockton; we're not going to change some of that infrastructure. But we need to decide how much is protectable and what to do with the rest. There's a lot of creative thinking out there that hasn't gone into planning yet." What he doesn't want to see, says Herbold, is islands lost to levee failures, the result being a bunch of semi-isolated deep ponds that "sit there and percolate, ruin water quality, and trap salt."
Maybe it's time for a Delta design charette, in which scientists and resource managers ponder all the questions facing the Delta. Says Herbold, "We need to get 30 people in a room for a week and have a serious conversation, identify goals and problems, and solve them. So far we haven't done that because people think they have the answer, or that someone else has the answer, and they don't like that answer." Yet with the governor allocating $16-$18 million in the general fund this year to prop up ailing Delta levees-and proposing a $900 million bond for fixing Delta levees over the next 10 years-we may only have a tiny window of opportunity in which to tackle the Delta's problems in an intelligent, non-kneejerk way, says Holmes. But Grindstaff says some of that levee money could be used to implement a new vision for the Delta.
A common vision, he says, is needed before any design charette can take place. "We have to find a way to involve the local communities and lots of stakeholders to come to an agreement on what we want to see in the Delta. We're going to try to foster [such a process]." Grindstaff's vision for the visioning process is to have a science panel available for policymakers to consult with as they discuss what to do about the Delta. Holmes thinks scientists should come up with the vision, with politicians locked out of the room. Hull says people would have to come with an "open mind," and let go of their orthodoxy that "less exports is the solution," which he likens to turning a knob that no longer works.
One key point on which most folks seem to agree, however, is that in any discussion or visioning process we also need to tackle the state's overall water use issues, particularly with the Central Valley's population predicted to increase by 131% by 2050. How do you get all of those new residents to understand they are living in a water-challenged state? "No one wants to tell people how to live, but if you tell people they can't have unlimited water in an arid state, they get it; they try," says Holmes. "Right now, there's a complete lack of leadership from the government in educating people about this." Says Grindstaff, "We need to find the right mixture of incentives-positive and negative-to get water agencies and the public in general to change their [water use] ways. Clearly, we have to do everything we can to reduce demand. The state as a whole has to get that ethic and that's something the state-CALFED, DWR-has to push." Says Swanson, "There are places where we could increase reliance on integrated regional supplies instead of imported supply [from the Delta]. There are huge opportunities for water conservation by both urban and agricultural areas, including land retirement."
Can the kaleidoscope of ideas ever coalesce into a coherent vision? U.C. Berkeley is holding one visioning process in March. Probably the only point on which everyone seems to agree right now is that we need to keep talking about the Delta and start dealing with its future, unless we want nature to do it for us, New Orleans style. Says Herbold, "We cannot bring all of those levees up to the federal standards needed to protect us from earthquakes and climate change. We should be asking 'What are the sustainable resources in the Delta?' Otherwise, we're just sitting on the tracks in a stupor as the train heads straight toward us."
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