The Twin Tunnels is a joint proposal by Governor Jerry Brown, the federal Interior Department and powerful agribusiness water contractors to maximize transfers of water from Northern California to Southern California as part of the administration’s the Bay-Delta Conservation Plan.  The scheme calls for three gigantic intakes located in the Sacramento/San Joaquin Delta that would connect to two subterranean tunnels, each 40 feet in diameter and approximately 30 miles long.  These twin tunnels would shunt high-quality fresh water from the Sacramento River for distribution via the State Water Project to San Joaquin Valley agribusiness, Silicon Valley and South State cities and suburbs.

Advocates maintain the Twin Tunnels will assure the state’s water security at a reasonable cost.  However, even a cursory analysis shows this claim is wildly off the mark.  Key problems facing the tunnels include:

  • A Massive Price Tag: Project costs are a moving target, but most analyses peg them at between $25 billion and $69 billion.  Paying off the bonds needed for the project will take decades.
  • Incomplete Design: The project’s schematics are a work in progress—as of this writing, only 10 percent of the design has been completed.  As the design is refined, costs likely will rise.  And as the physical costs of construction rise, interest costs will appreciate as well.
  • Magical Thinking: The claim that the project will increase water supply reliability is either disingenuous or deeply delusional.  If the project is operated with Delta protection as a goal, it will deliver less water than current Delta regulations allow.
  • Robbing Peter to Pay Paul: The Twin Tunnels will improve the quality of imported water at the cost of degraded Delta water quality, directing harming the estuary’s farmers and aquatic ecosystems.
  • Inadequate Habitat Restoration: The Bay Delta Conservation Plan’s habitat restoration programs are meager at best.  They skimp on the water essential to maintaining fisheries at their current low levels, let alone restoring them to any degree.
  • Inaccurate Evaluation of Levee Status: The state claims the Delta’s levees are fragile and vulnerable to catastrophic seismic failure — but the estuary’s levee system held during the massive Loma Prieta earthquake of 1989.  The major seismic threat to the Delta is the Hayward Fault, which is a full forty miles to the west; no active faults exist in or near the Delta.  Bringing all Delta levees up to modern standards would cost only $2 to $4 billion – far less than the $25 billion to $60 billion required for the Twin Tunnels.


County of SBThe environmental downside of the Twin Tunnels is profound.  But for Santa Barbara ratepayers, the most pressing problem with the BDCP and the Twin Tunnels is cost. Based on information from both the state and federal governments, the total cost for the project will range from $20.6 billion to $68.8 billion. Based on this data, C-WIN estimates that Santa Barbara County water districts will be liable for principal and interest costs ranging from $776 million to $5.12 billion—or more.

Moreover, the Brown administration has arranged for the project to move forward without a vote of water ratepayers.  In other words, the people who will be responsible for paying for the Twin Tunnels will have no say in whether or not they should be built.

Because the costs of the Twin Tunnels must be borne by ratepayers, water bills could increase significantly for Santa Barbara households.  A white paper by ECONorthwest Economic Consultants found that maximum rate increases for Santa Barbara ratepayers would range between $287 per year (about $24 more per month than the current average water bill) to $1,920 per year (about $160 more per month) by 2019.

State Projects Map

If built, the Twin Tunnels will shunt water to the State Water Project (SWP), which will then transport it to Santa Barbara County.  The SWP
has a troublesome history with the county.  In 1991, voters approved construction of the Coastal Branch, an aqueduct that connected Santa Barbara County to the SWP.  At the time, it seemed a reasonable decision.  The state Department of Water Resources (DWR) assured ratepayers the project would cost no more than $270 million.  By the time the real costs of construction, maintenance and debt service were folded in, however, the total price tag tallied $1.76 billion—a crushing debt that will encumber county ratepayers for decades.

And it’s not just the cost of State Water Project Water that’s at issue: DWR’s promises of dependable water deliveries have not been met.  State water reliability is determined by the percentage of contracted amounts delivered each year. In 1991, DWR promised Santa Barbara County 97 percent reliability in Coastal Branch deliveries.  That pledge never came close to being fulfilled.  Between 1998 and 2011, the average reliability of state water deliveries for the four coastal water agencies was 36 percent and 69 percent for Santa Maria.

Santa Barbara County has also suffered from sweetheart deals between DWR and large Central Valley contractors.  Historically, urban districts were given priority over agriculture for available water.  But beginning in 1995, that arrangement was reversed due to a backroom accord known as the Monterey Agreement.  Under this new arrangement, state water deliveries to municipalities can now drop to as low as 5 percent of contracted amounts—a cutback that represents genuine catastrophe for urban ratepayers rather than mere hardship.  C-WIN is litigating this contact change.

In 2012, the Montecito Water District devoted $5.4 million of its total $12 million budget to SWP water —but the benefits to the district have been minimal.  Multiple retail price increases have reduced water demand, a phenomenon known as “price elasticity:” when a commodity rapidly escalates in price, consumers reduce usage.  C-WIN’s research demonstrates other Santa Barbara County water agencies have been hobbled by the high price of SWP water, infuriating ratepayers.

Local SB County Service Area


  • As a State Water Project contractor, the Santa Barbara County Board of Supervisors should vote the county out of the fiscally unsound Twin Tunnels/Bay Delta Conservation Plan and decline early renewal of its State Water Project contract.  C-WIN supports continued delivery of State Water Project water to Santa Barbara County and renewal of the county’s contract prior to its 2038 expiration, but opposes early renewal as a financing mechanism for the Twin Tunnels.
  • Water agencies serving the Santa Barbara Coastal Plain should go on record opposing the Twin Tunnels project, given that this project would increase financial obligations for already pricey state water to a prohibitive degree.
  • Coastal Plain water agencies also should advocate for the return of the urban preference for State Water Project service contracts, a move that would protect local ratepayers from unreasonable rate hikes and reduced SWP deliveries during drought years.
  • The four South Coast water agencies served by the SWP can minimize costs by utilizing cheaper and more reliable alternative sources of water.  These include Lake Cachuma, conservation, stormwater capture, local streams and reservoirs, groundwater, recycled water and desalinated water.