COURTLAND, Calif. — On the last Sunday of July, this small town in the Sacramento River’s delta takes a pause from the peak of the pear harvest season by holding its annual pear fair. A pear run, a pear parade, a pear pie eating contest and a pear fair queen are as much a part of life’s rhythm here as the pruning, picking and packing of pears.

But not far from the booths offering baskets of the fruit, and pear drinks and pear sausage, there were hints this summer that something was ruffling Courtland. At the same booth where a handwritten sign advertised “Pear oatmeal cookies, 2 for $3,” there were pointed political messages like this one: “Build the tunnel. Kill the delta.”

Just a few days earlier, state and federal officials announced plans to build twin 35-mile tunnels that would tap water from the Sacramento River at intake stations here. Like highways with no exits, the $14 billion giant pipelines would run under the delta in a straight line and deliver the water to aqueducts that feed water to large corporate farms and densely populated regions in Central and Southern California.

Supporters say the pipelines will improve the environment of an increasingly fragile delta by replacing the pumps that now suck water directly from the southern delta. More than anything else, backers — led by Gov. Jerry Brown, who failed in his bid to build a similar project in his first term as governor three decades ago — say the tunnels will secure a supply of water to California’s most economically vital areas.