LOS ANGELES _ Southern California's biggest water agency voted Tuesday to shoulder most of the cost of replumbing the troubled center of the state's vast waterworks, committing nearly $11 billion to the construction of two massive water tunnels.
The approval pushes ahead a controversial infrastructure project that has dominated discussions of how to halt the steep ecological decline of the Sacramento-San Joaquin Delta _ a decline that has threatened water deliveries to 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 Southern California Metropolitan Water District 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 at least partially removes a major stumbling block to a delta revamping that MWD's influential staff has insisted is vital to sustaining deliveries that make up roughly a third of Southern California'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 scheme fell apart last year when the big San Joaquin Valley agricultural districts that were supposed to pick up nearly half of the proposed $17 billion bill to construct two giant 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 delta 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 the delta operations, 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 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 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 Southern California than one tunnel, they also insisted that Southern California shouldn't have to foot the bill for the extra capacity.
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 Southern California 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.
