This week, Governor Jerry Brown’s controversial water project is back in the public eye. State officials are launching a marathon series of hearings for the “twin tunnels,” as they’re known, that will ultimately decide the fate of the project.

What are the Delta water tunnels?

They’re two, 30-mile water tunnels that would be built in the Sacramento-San Joaquin Delta, east of the San Francisco Bay Area. Each tunnel would be 40 feet in diameter, larger than the tunnels that carry BART trains under San Francisco Bay. The project, dubbed “California WaterFix,” would be buried 150 feet below ground.

What’s the California Delta, again?

It’s a huge, inland estuary where Northern California’s major rivers converge before the water flows out to San Francisco Bay. It used to be mostly wetlands and marshes, but much of the land was converted to farming.

Who would get water from the tunnels?

The tunnels would be part of the state’s major water system that serves about 25 million Californians, from the Bay Area to San Diego. Built more than 50 years ago, the network of reservoirs, canals and aqueducts stretches hundreds of miles.

It’s designed to fix a tricky problem that state planners ran into a century ago. Most of the rain and snow falls in Northern California, but most of the state’s population (and many farms) reside in Central and Southern California.

Proposed Route of Delta Water Tunnels

Huge underground project would divert water from the Sacramento River for export to Central and Southern California.



Why Does the Brown Administration want to build them?

The recent drought may have brought water battles to the forefront, but those battles are a perennial feature of California politics. That’s because the central hub of this water system, the Sacramento-San Joaquin Delta, is in bad shape.

Water is drawn from the Delta by two massive pumping facilities that can move millions of gallon per minute. They’re so powerful that they’ve been shown to entrap endangered fish, like Chinook salmon and Delta smelt. When those species are at greatest risk, regulations require slowing down the pumps, potentially limiting how much water reaches cities and farms.

The twin tunnels would take water from farther north near the Sacramento River, and deliver it to the pumping facilities. State officials say that would make the water system more reliable, because the pumps would be used less, avoiding the impacts on endangered species.

How much would the tunnels cost and who would pay for them?

They aren’t cheap. Construction could cost $14.9 billion. Add in mitigation costs for construction impacts, operations and maintenance and the tab runs to about $17 billion over 50 years — and that doesn’t count paying off the bonds that would finance the project.

Ostensibly, it would be paid for by the water agencies that get the water, including urban water districts in the southern Bay Area and Southern California, as well as agricultural water districts in the Central Valley. Those agencies would have to raise water rates or possibly property taxes to cover the cost.

Who is against building the tunnels?

A lot of people. Residents that live in the Sacramento-San Joaquin Delta don’t want a major construction project in their backyard and are concerned it could affect their water quality.

Some environmental groups say the tunnels, as they’re designed now, could make things worse for endangered salmon and other fish as too much fresh water is removed from the ecosystem, though there are other issues as well, like habitat loss and invasive species. Environmentalists say that the tunnels would simply continue the trend of removing too much fresh water.

So how much water will the tunnels take out of the Delta?

Hmm, good question. State officials have proposed a range of scenarios. At one end of the range, water users could see more water delivered to them. At the other end, they’d get less, but more would be left in the ecosystem.

But here’s the hitch: several of the water agencies that would pay to construct the tunnels have said they can’t justify the costs if there’s a chance they’ll end up with less water.

So, why should I care about this?

California’s water problems aren’t going away. There will be more droughts, more conservation rules and more challenges ahead, especially with climate change.

The state’s water system, as ambitious as it was a half-century ago, can’t keep up with current (let alone future) demands. So whether fixing that problem involves massive water tunnels, or simply finding ways to do more with less water, Californians are going to have to do something.

Who will decide if the tunnels get built?

Now it’s up to state and federal agencies. The State Water Resources Control Board is beginning hearings to answer two questions: will the tunnels impinge on anyone else’s right to use water and will they harm endangered species? Those hearings could go on for quite a while, maybe until mid-2017.

State and federal wildlife agencies will look at whether the project will harm endangered salmon and Delta smelt, as well as other species. And in their review, they will determine how much water the Delta tunnels can deliver in order to ensure that species don’t go extinct.

That decision could determine whether water agencies are in or out, ultimately deciding the fate of the project. Oh yeah, and the whole thing is likely to end up in court, no matter what the decision.

What about a public vote? There’s a November ballot measure that would require votes for big infrastructure projects.

True. If passed, Proposition 53 would require a public vote on projects backed by state-issued revenue bonds over $2 billion, including this one.

If the bonds to pay for the tunnels are issued by the water agencies, not the state, then a public vote might not be required under Prop 53. But some analysts say the individual agencies, even banding together, would have a tough time floating bonds for the project on their own.

About That $17 Billion Water Project: Delta Tunnels 101 4 October,2016Lauren Sommer

  • Chris Gilbert

    Most participants in the discussion admit that little if any additional water will be delivered to the south. For that reason alone, water agencies will see it’s not in their interest. There just isn’t enough water to satisfy everyone’s needs. Water rights “on paper” (under 100+ year old rules) exceed water availability by 500%. It’s a broken water system and these tunnels aren’t going to solve it.

    The money would be better spent on conservation, reinforcing the levees, and paying to take salt-saturated farm land requiring irrigation in the southern Central Valley out of production. And if drought is really the new normal according to climate experts, we’ll have less water in the future, in any case. Tunnels won’t fix that unless we totally abandon the Delta, putting an end to the salmon and other fisheries in this area of the country. And the expansion of nut farms in the south Central Valley (one source says there is a mini-boom in bank lending to start new farms there), a single nut of which takes a gallon of water, and of which 70% are exported, is not the direction we should be going in a semi-arid environment. By definition they lock in water use because you can’t fallow nut trees during a dry year; they need water always.

    80% of water use is for agriculture while it contributes only 2% to California’s economy. Priorities are warped here.

    • solodoctor

      Many valid points made by Chris. To which I would add one more, underlying one:. These tunnels will give water agencies, ag users, and urbanites the illusion that it would be alright to maintain the status quo when it comes to water use in Calif.

      Even without a drought and the effects of climate change on our supply of water, our growing population in and of itself means we must use this precious resource more efficiently. Eg, water intensive crops and existing urban landscapes which require a lot of water must give way to new modes of food production and living. At best, these tunnels will not help move things in that direction. More likely, the tunnels will encourage people to continue their excessive use of water.

    • Guy Morgan, Jr.

      Chris makes good points. One area I take exception with is almonds. The almond concerns are real, but what is the alternative? Milk? how much water, methane, land, etc. does a gallon of milk require, generate? But in general, what is really crazy about this whole argument is that California does not have enough water now. And no matter what we do, there’s not going to suddenly be enough. At the same time, while we here in the North have done a good job of knocking down our water use, Southern California has not done nearly as good a job. Just fly over, and see the number of swimming pools across LA evaporating all that water. But the real issue is that this is mostly a desert state, and we keep adding more people. Look at the number of cranes in downtown San Jose, San Francisco. This state can not support 38 million people today, and then 2 or 3 times that amount in the near future. We do not seem to have a head that on this body of our state can think or see the obvious, and we just keep doing things that really do not make any sense, meanwhile, we don’t point out the most glaringly obvious dilemma of today: We cannot keep adding people or sustain agribusiness to the already deficient water system.

      • Chris Gilbert

        The alternative I see is to take the land out of production, not replace nut trees with other agriculture. Much of it is in the far reaches of southern Central Valley and basically desert, and becoming so polluted with selenium and other chemicals because of lack of drainage that it will take a lot to clean it up for continued use in the not too distant future, anyway.

        Again, since 80% of our water use is in agriculture we have a lot to work with if we start taking the poorest lands out of production.

    • Mr. Kurtz

      Agriculture accounts for 2% of our State’s GDP if you count only
      farm-gate value. Processing, transportation, and distribution account
      for an additional 4%, and 600,000 jobs. (Do you value only the grapes
      that go into wine, for instance?). The “80% of developed water that
      agriculture uses” does not take into account the food that 38 million
      people eat three times a day. Without all those agricultural users, urban customers would have to bear the entire overhead of our water systems, and costs would skyrocket. The argument against exports is
      totally bogus. California is a net importer of water when you take into
      account the things we buy from elsewhere. If we should not ship food to
      China, why should we ship it to Chicago? Finally, if you pitch
      agriculture out of California, it will take place somewhere else without the
      food safety, worker safety, and environmental protections we have here.
      We’ll also burn a hell of a lot of fuel importing all that stuff. I fail to
      see how that would be an improvement.

      • Chris Gilbert

        600,000 jobs out of 18 million is only 3%. So my assertion stands: agriculture is a minor contributor to our economy. Ultimately residential use will force water distribution from agriculture to towns and cities, esp. as we reach 50 million, it’s just a matter of how long we’re willing to destroy the environment before we acknowledge that.

        As far as water costs, they are currently hugely subsidized, so the taxpayer, and not just from California, bears the large burden of water distribution. Extractive industries and I include agriculture, have historically got an incredible deal in the use of public resources. With water (read Cadillac Desert), costs that were supposed to be born by agriculture have not been.

        • Mr. Kurtz

          Sorry, I failed to make myself clear. Agriculture itself employs about 375,000 people, and the dependent industries employ another 600,000.I suppose the near million little people can lose their jobs if we can not achieve some imagined Arcadian paradise.
          Why should agriculture bear all the burden when land use, manufacturing, flood control, green power generation, invasive species, and commercial fishing play important roles in the problems? Only a small portion of water is subsidized, and 80-90% of that has not been delivered for several years. You have not mentioned how the entire capital cost and overhead of the water projects will be allocated to urban users. The capacity of the existing systems is vastly in excess of the water consumption (excluding food) needs of 50 million people. That capacity has to be paid for. Nor have you suggested some other place where California’s production could be relocated, and why that would be better.
          I am one of the parties acknowledged by the author in Cadillac Desert, you don’t need to tell me about it. It was also written a long time ago, and Marc revised his thinking considerably before his death.

          • Chris Gilbert

            So adding the 375,000 to the previously mentioned 600,000 it comes to 4% of employment; once again, a very small portion of California’s economy. And they are mostly low-paying jobs. Not a place for much opportunity except by large corporations that can lobby to increase water distribution in spite of scientific evidence that the Delta and other parts of the state are in severe decline. The amount of irrigated agriculture we have in the state and in the west in general is way too extensive given the resources, and has a limited life; I’m just hoping that certain areas of the state will not be totally destroyed.

            Are you saying that Marc Reisner recanted his extensive evidence as to the misguided and often corrupt practices that built the western water systems, in the beginning mainly for agriculture? That would take another book in itself. I’d love to know the title, or where to look for that info.

          • Mr. Kurtz

            I guess you’re right, the livelihoods of a million people and their families (and their communities) hardly compare to the needs of fish. I’ve spent nearly 40 years in agriculture, and have been intimately involved with water issues. With the exception of the Environmental Defense Fund, the Nature Conservancy, and Audubon, the environmentalists have been universally doctrinaire, eager to litigate, and completely devoid of creative thinking. That’s why nothing gets done, or will get done, until there is some big crisis like a critical levee collapse, with potentially devastating economic and public safety consequences. Then nobody will give a rat’s ass about the environment, they’ll just build something pronto. What a waste.

          • Chris Gilbert

            Just like with coal, there are certain industries where the cost to the public interest is greater than the cost in the loss of jobs. Of course there needs to be a safety net, just like with globalization; people need to be re-trained, etc.

            I want to underline that I’m not proposing that all agriculture be gotten rid of in California; just that there are vast swaths of semi-arid, increasingly marginal land where at this moment new nut farms and other crops are being planted, to the detriment of the people and environment of this state.

          • Mr. Kurtz

            You’re right, we have both been using rather extreme examples for rhetorical effect. Unfortunately, most of the land to which you refer has already been taken out of production. What is happening now is that some of the most fertile and productive land is being taken out of production. This is not so much a result of water shortages, but because water can not be moved through the Delta in a manner that satisfies the environmentalists. Shasta reservoir is still nearly full. Nearly 1.5 million acre feet of water was allowed to flush out to sea this last winter, with nothing to show for it.
            BTW a lot of farmers have taken out mature orchards and planted new ones, because little trees use less water than big trees. This is a desperation strategy. The economic and human cost of our failed Delta management is real. The status quo helps neither farmers nor fish.

          • Chris Gilbert

            But the polluted land is being created by the farming! It has poor drainage so over time nitrates and salts build up. There are communities now without drinking water because of the pollution. Again the land in the southern portion of Central Valley, especially on the west is not suited to agriculture. And if you drive down Hwy 5 thought that very area you will see an abundance of new nut tree farms, made possible by lucrative crops, subsidized water, large amounts of cash from large corporations and investment funds, and wrong priorities.

          • Mr. Kurtz

            Your information is out of date, and, in part inaccurate. The land along I-5 is some of the finest farmland in the world, 40 feet of Class I topsoils. It lacks water, which is why the Federal Government initiated yet another of its infamous “infrastructure projects” to deliver water to it, and relieve the subsidence that was taking place from well pumping. The enabling legislation also required the Bureau of Reclamation to provide drainage facilities, which they never did. The catastrophe at Kesterson was the result.
            The lands along I-5 have excellent drainage; the drain water ends up 10-30 miles away in an area with comparatively lousy soils. Several hundred thousand acres of this land have already been retired, and a facility to process and clean up the drain water has been in operation for several years. The selenium is naturally occurring.
            The communities with high nitrate levels in their drinking water are mostly on the east side of the valley, or much further north than the area under discussion. And, as I mentioned, the water subsidies were de minims when they existed (forgiveness of interest on certain capital costs, amounting to something like $10 per acre foot, when water costs a minimum of $300 per acre foot). Now that water is not being delivered, the subsidy issue is moot.

          • Chris Gilbert

            I’m beginning to wonder about the credibility of Mr. Kurtz. The towns that are considered to have poor soils and are struggling are exactly along Hwy 5: Huron, Avenal, Lost Hills, and the Westlands Water District in general. I’m including several articles, one on SF Gate and a map of the area. I think I’ll conclude this discussion.



          • Mr. Kurtz

            Lost Hills and Avenal are served by the State Water Project, which is is an entirely different kettle of fish. Huron is several miles away from the highway. The nitrate problem there is being caused by animal agriculture.
            Anyway, nice talking to you.

  • This is one reason as a Northern CA citizen, that i am not saving water anymore! we are just saving so LA and San Diego can keep it’s Golf courses going!

    • Chris Gilbert

      It might be more useful to join with LA & San Diego in our common interests as urban users (of course there will need to be less wasteful use for residential users), and start to address the idea that agriculture is untouchable, especially when in the southern Central Valley they are very large corporations, many of which aren’t basically in farming but do it on the side because certain crops are so lucrative, esp. with the subsidized water that the U.S. and Calif. have been providing for the last 100+ years.

  • ericmills

    The Elephant in the Room which is almost NEVER addressed is California’s gross human over-population. Thirty-eight million and counting, with an estimated additional 25 million by mid-century. Not sustainable! Until we get a handle on our numbers, our water problems will never be resolved, and we and the environment will suffer accordingly.

  • EmGe

    Would like to see more discussion about risk and reliability – I view the fix as not changing the environmental impact (specifically fish) nor the water allocations, but rather, greatly increasing the reliability of a system that could be crippled in an acute shock earthquake, where in a single moment multiple levees fail releasing salt water into the system effectively shutting it down for 6 to 24 months, or in a chronic case, sea level rise in essence creates the same scenario as bay pressures push salt water further east toward existing pumps over this century.

  • Allison Martin

    An updated article on the twin tunnels would be timely since the Final EIS/EIR have been published now.

  • Jerry Krebs

    You guys haven’t discussed the addition of Sites Reservoir to the mix-if we didn’t have as many environmental restrictions, Sites would be a reality sooner then projected.

  • John Charles Lipka

    Why not include some hydro-electric functions to offset the costs of pumping? Surely there must be adequate elevation drop in some areas.

  • Brian

    I am 100% against the tunnels. That being said, In fairness to LA and San San Diego, most the golf courses, are using reclaimed water to keep the courses green. The state should be focusing their attention on two issues. Coming up with a plan that will allow for the capture and storage of rain water in the southern part of the state. Almost all of the rain that falls in the southern part of the state flows directly into the ocean. Second it’s time for this state to enforce US immigration laws. A sanctuary state right on the border is not a wise decision.By sending the message that those who come here illegally will be welcomed, is just encouraging more people to come here . State social services are already overwhelmed, and the states infrastructure is already showing the strain and is beginning to crumble.Enforce the immigration laws, those who broke the law must go, we simply can not afford them anymore.


Lauren Sommer

Lauren is a radio reporter covering environment, water, and energy for KQED Science. As part of her day job, she has scaled Sierra Nevada peaks, run from charging elephant seals, and desperately tried to get her sea legs – all in pursuit of good radio. Her work has appeared on Marketplace, Living on Earth, Science Friday and NPR’s Morning Edition and All Things Considered. You can find her on Twitter at @lesommer.

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