The California Delta: a catastrophe of biblical proportions in the making? Or the system – natural and political – working the way it should? Jane Wolff, author of Delta Primer: A Field Guide to the California Delta explains.
Published: June, 2004
Jane Wolff is the author of Delta Primer: A Field Guide to the California Delta. After studying
documentary filmmaking and getting a graduate degree in landscape architecture, she worked in a landscape architecture office in San Francisco. A traveling fellowship took her to the Netherlands to study the history of land reclamation. That experience led to her interest in the Delta.
BC: What’s the background of this book?
JW: I started the project to educate broad audiences about the Delta and its importance to California’s future. I’d had an eye-opening experience at a job with some landscape architects in Silicon Valley in the mid-1990s. I’d never spent any time in the suburbs before, and I found myself working on a housing project on the last orchard in Cupertino. I was really shocked at the way development was homogenizing the Santa Clara Valley, and it bothered me that design professionals weren’t doing anything to question the agenda of the developers. I wondered what someone like me could do to suggest other alternatives for the future of the landscape.
I left the Silicon Valley job and started teaching part-time at the California College of Arts and Crafts. I first heard about the Delta from a friend at CCAC, who thought it sounded similar to the Netherlands. I got even more interested when I found out that the Delta’s at the center of all the issues that are shaping California’s landscape–the changing economics of agriculture, environmental politics, suburban development, and the endless demand for water. The Delta’s a critical link in California’s ecology and economy, but most of the people in the state don’t even know it exists. That’s a huge problem.
I started the project in my spare time while I taught at CCAC and kept working on it when I went back into practice as a designer. Eventually I realized that an academic job would be a better platform. So I started teaching full time, first at Ohio State and then in the architecture and urban design programs at Washington University.
BC: The Delta’s manmade, isn’t it?
JW: That’s too simple. It’s really a product of interactions between natural processes and what people have done. In 1850, when California was first being settled, the whole region between Sacramento and Tracy and between Stockton and Suisun Bay was a tidal estuary. The Sacramento River, the San Joaquin, and all of their tributaries came together there and formed the Delta, where their water spread out again in rivers and sloughs that are called distributary channels. From the Delta, all that water went into the Bay. The land was just above sea level, and it was covered with cattails and tules.
In 1851, the Swamp and Overflowed Lands Act made land ownership in the Delta possible, and people started reclaiming it. First, they built small levees to protect the land from seasonal flooding. Then they began farming.
Those two activities changed the Delta forever in ways that no one had expected. For one thing, the soil, which was peat, began to react with oxygen, and it literally disappeared into the air. The level of the ground got lower and lower. At the same time, the levees were making the level of water in the rivers higher and higher. During floods they stopped the rivers from spreading out over the land, but that meant the water held in the channels was higher than it would have been naturally. It also meant that the alluvial material carried by the rivers was deposited in the channels instead of on the floodplain, and so the channel bottoms got higher too. Flooding became a hazard all the time, not just during the rainy season.
Now most of the Delta is below sea level, and it has to be protected by big levees. Some of the Delta’s islands are 20 feet below the level of the water in the rivers. Keeping the land dry is a big problem. Groundwater comes to the surface on the subsided islands, and it has to be pumped up and out into the rivers.
BC: What other changes have people made to the landscape?
JW: The Delta has become a primary water source for Southern California. In the ’50s, the federal government began pumping water from the Delta to farmers in the San Joaquin Valley. Then, in the ’70s, the state began pumping to Los Angeles and San Diego. The Delta’s importance to those metropolitan centers is going to become even greater because of what’s happening in Colorado River politics.
For a long time, Los Angeles got more than its share of water from the Colorado because upstream states like Nevada, Arizona, and New Mexico didn’t use all the water that was supposed to be theirs. Now the population in those places has boomed, and technology has been developed to hold the water until people need it. The process is called groundwater banking: water from the Colorado is put into the aquifer and held there until it’s wanted. So the upstream states won’t let Los Angeles have their water allotments anymore.
BC: What’s the worst that could happen with the Delta?
JW: The answer to that question depends on who you are. Part of what’s so amazing about the Delta is that the landscape functions in a really complex way. It’s a unique habitat for species that don’t exist anywhere else. It’s incredibly productive farmland. It’s the backyard for rapidly growing cities like Sacramento and Stockton. And it’s a water supply for the south.
For farmers and environmentalists, the worst scenario is that all the water could be sent to the southern part of the state. For water users in the south, the worst scenario is that the Delta’s islands could flood and the water would become salty.
BC: Why would that happen?
JW: The Delta is where salt water from the Bay meets the fresh water that’s coming from the rivers. The water’s all traveling through narrow channels, so the fresh water is able to hold the salt water back. If the fresh water is spread out over a greater area, the salt water will move east, and the water won’t be suitable for drinking or irrigation anymore.
If a lot of levees broke, it would be a catastrophe. That’s why the Department of Water Resources and the Corps of Engineers work with farmers and reclamation districts who own and maintain the levees to try to prevent breaches.
BC: What about the Peripheral Canal–could it be reintroduced?
JW: The Peripheral Canal would have taken water from the Sacramento River, above the Delta, directly to the pumps that send water south. It was voted down in 1982 because people were concerned that once the capacity existed to take water around the Delta, there was no guarantee that any water would be left. Los Angeles might be more secure, but the Delta’s incredibly rich farmland and unique ecosystem could be deprived of water.
Since then, a consortium of state and federal agencies called CALFED has been formed to manage the Delta. It’s a tough challenge. CALFED’s mandate is complicated, even contradictory–it’s charged with maintaining environmental quality in the Delta and with increasing water supplies for the southern part of the state. In the late 1990s, CALFED proposed different options for the Delta, and one looked a lot like the Peripheral Canal. The final decision was to maintain the system the way it was, though, with smaller-scale interventions to make water movement more efficient and to improve environmental quality. That decision was made because people with local interests in the Delta were afraid that the new canal would pose the same potential problem as the Peripheral Canal.
BC: Is there a solution to the problems in the Delta?
JW: I don’t know if there’s a single solution, but I think the best scenario for the future depends on balancing the needs of all the people who’ve come to depend on the Delta. That means everybody has to share, and everybody has to respect the needs of other constituencies.
BC: Are there any examples that people can look to?
JW: Actually, there are places in the Delta that already accommodate multiple interests. One is the Yolo Bypass, which forms the western edge of the Delta. The bypass is farmland, and it’s also a spillway for the Sacramento River. You’re only allowed to grow crops that won’t stop floodwater. When the level of water in the Sacramento River gets too high, floodgates to the spillway are opened, the water flows over and through the farmland, and the city of Sacramento stays dry. When the farmland is flooded, it also becomes great habitat for migrating birds. So the landscape is able to do a lot of different things at the same time.
Another example is the Cosumnes River Preserve. The Nature Conservancy is working there to restore floodplains and promote sustainable farming along the Cosumnes River. They’re helping to avert flooding downstream, they’re making habitat, they’re cultivating the land, and they’re providing a place where people from the city can watch birds and go for walks.
BC: Do you think the official process is going to address this?
JW: Everybody I know who’s involved in the management of land and water in the Delta believes in the uniqueness and importance of the landscape and regards it with care and respect. It’s easy to point fingers and say that someone else is causing the problem, but I don’t think that’s fair. It’s just that, as a society, we want a lot of different things from the same place. What’s problematic about the process is that it hasn’t reached enough people.
BC: With the ground dropping and the water being drained out in amounts that are going to increase as the population grows, can the Delta survive?
JW: I don’t know, but we have to try to save it. The Delta’s a resource that can’t be replaced, and none of the transformations it’s undergone can be undone. All we can do is go forward, and we have to balance a lot of different issues. That’s why it’s so important that people understand the Delta’s enormous value. It’s not just a problem for the government, or for people who are interested in wildlife habitat, or for people who farm there, or for people who live in the cities nearby. Everyone in California depends on the Delta in one way or another, and they all need to know why.
