SACRAMENTO (CBS/AP) — A measure expected to qualify for the November 2016 ballot could threaten Gov. Jerry Brown’s $15 billion twin tunnel plan to send water around the Sacramento-San Joaquin Delta.

The Sacramento Bee reports Sunday signature gatherers paid by wealthy Stockton-area farmer Dean Cortopassi are circulating an initiative to force large public works projects to go before voters for approval.

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Cortopassi’s measure could make it harder to secure lucrative public works contracts and, in the case of the tunnels project, water deliveries.

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The Bay Delta Conservation Plan calls for building two underground tunnels, 40 feet across and 30 miles long, to send water from the Sacramento River around the Delta. The water currently irrigates 3 million acres of farmland in the Central Valley and serves 25 million people as far south as San Diego.

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