FRESNO, Calif. (AP) -- A proposed twin-tunnel water system in the Sacramento-San Joaquin Delta coupled with a massive habitat restoration effort would generate billions of dollars in economic activity for California, according to an economic report released by state water officials on Monday.
Implementation of the Bay Delta Conservation Plan would lead to $4.8 billion to $5.4 billion in economic benefits for California water users.
The tunnels would provide a new avenue for shipping water from the delta south to farms and cities.
The analysis also found that building the tunnels would create thousands of construction jobs and increase recreational opportunities and jobs in the delta. The project would also prevent further water delivery cuts and save about a million agricultural jobs that might otherwise be lost as a result of stricter environmental flow requirements to protect threatened fish.
Critics say the analysis is biased and incomplete, and that the state has exaggerated benefits of water reliability while underestimating negative impacts on the delta.
The tunnels, critics say, would devastate delta agriculture, recreation and fisheries because they would suck more water from the estuary. And because the impacts of habitat restoration on fish are not known, they say the idea that more habitat could save dwindling fish species and create jobs is an assumption that may prove untrue.
Though the study was not able to quantify the tunnels' impacts on commercial fisheries, water officials say those impacts would be positive.
The study also predicts annual decreases in agricultural revenues in the delta region of $1.86 million and an additional $3 billion loss of economic activity over a 50-year period as a result of agricultural land retirement in the delta. Transportation disruptions and delays due to construction of the giant tunnels were estimated to range from $53 million to $79 million.
The economic analysis assumes that without the tunnels, future conditions in the delta will get worse and there will be further water delivery cutbacks. The analysis does not take into account the $4 billion that federal taxpayers would bear to pay for habitat restoration costs.
The total cost of the tunnel-conservation plan is estimated at $25 billion. Water districts would put up more than $17 billion for tunnel construction, operation and mitigation. Another $8 billion for restoring more than 100,000 acres of floodplains and tidal marsh would come from state and federal funds, including state water bonds.
If voters fail to approve the water bonds, critics say, assumed benefits stemming from habitat restoration would not materialize.