The Metropolitan Water District of Southern California voted Tuesday to shoulder most of the cost of revamping the system that delivers water from the Sacramento-San Joaquin delta to the Southland, committing nearly $11 billion to building two massive tunnels.

The approval, by a surprisingly strong margin, pushes ahead a controversial infrastructure project that has dominated discussions of how to halt the delta’s steep ecological decline — a decline that has threatened water deliveries to Los Angeles and other parts of the state’s most populous region.

A top priority of Gov. Jerry Brown’s administration, the tunnels project has been in the planning stages for more than a decade.

The MWD vote does not assure that it will be built. The project has yet to obtain key permits and faces years of legal challenges by opponents who consider it a costly diversion from more-sustainable water development projects such as recycling and storm water capture.


But it helps clear the path for an overhaul that MWD’s influential staff has insisted is vital to sustaining deliveries that make up roughly a third of the Southland’s water supply.

The vote capped months of back and forth over tunnel financing, which emerged as a make-or-break issue for one of the most ambitious water projects proposed in California in decades.

The original funding plan fell apart last year when the big San Joaquin Valley agricultural districts, which were supposed to pick up nearly half of the proposed $17-billion bill to construct two 35-mile water tunnels under the delta, backed out.

Ultimately two options emerged: Build a cheaper, one-tunnel version that would be financed by MWD and the mostly urban districts that get delta water deliveries from the State Water Project. Or have MWD pay for roughly two-thirds of the twin tunnel project, with other districts supplying the rest.


The funding debate inevitably reflected the conflicts over California’s water use and the environment.

The project — known as California WaterFix — is fundamentally an attempt to maintain a robust level of deliveries to San Joaquin Valley agribusiness and Southern California cities. Those deliveries have been subject to growing limits triggered by the harmful effects of water exports on the delta environment.

By modifying the way some supplies are routed through the delta, the tunnels are designed to lessen those impacts and thus avert further export restrictions. Proponents also say the tunnels will make a key part of the state’s water system less vulnerable to earthquakes and rising sea levels.

Opponents — primarily delta interests and major environmental groups — argue that the twin tunnels would inevitably be used to rob the delta of more fresh water. The answer to the delta’s problems is to reduce exports and develop more local supplies, they say.


Agriculture’s unwillingness to help pay for a project that it arguably needs more than urban districts — which have more diverse water sources — highlighted the degree to which the state’s fruit-and-vegetable garden depends on federal water projects that provide cheap supplies subsidized by taxpayers.

The conflicts were evident in the fractious board debate leading up to Tuesday’s vote.

Delegations from Los Angeles and the San Diego County Water Authority, both of which are working to reduce reliance on imported supplies and develop more local sources, led the fight against MWD taking on most of the two-tunnel bill.

An $11-billion tunnel bill was financially risky, they argued. Since an MWD analysis concluded that two tunnels wouldn’t send any more water to the Southland than one tunnel, they also insisted that Southern California shouldn’t have to foot the bill for the extra capacity.


“We don’t sit here today to tax our members for the entire state of California,” Los Angeles delegate Lorraine Paskett said. “I can’t support a vote that will put our ratepayers at risk.”

MWD has projected that investing roughly $11 billion in the tunnels would raise residential rates by $60 a year. Opponents contend the increase could be far greater.

The board’s twin-tunnel proponents, led by the Municipal Water District of Orange County, argued that building the full project would give water managers more flexibility in running delta operations, provide greater capacity to divert water during high flows and ultimately do a better job of sustaining delta deliveries that the Southland can’t do without.

They also predicted that MWD could recoup its extra investment by selling tunnel supplies to growers once the project was finished.


“I believe ag will be there,” said board Chairman Randy Record, who represents parts of Riverside County and voted for two-tunnel financing. “We don’t think ultimately we’ll have to pay for all of it.”

Although board members had predicted a close vote, the motion to fund both tunnels passed 61% to 39%. MWD weights member agency votes according to the assessed property values of their service areas. The two agencies with the largest votes, the city of Los Angeles and the San Diego authority, voted no, along with Santa Monica and San Fernando.

The vote authorizes MWD to fund roughly two-thirds of the full tunnel project, or $10.8 billion. But it doesn’t irrevocably bind the board, which could pull back if permitting issues force changes in the project.

“There are things that we don’t know how they’ll turn out,” Record said. “But I really believe … it’s appropriate for Met to send a signal that we believe in the value of this project, that we’re willing to move forward to do what we can to make that happen.”


UPDATES:

8:15 p.m.: This article was updated to include additional details from the vote and comments.

This article was originally published at 3:45 p.m.