Folsom depends on a single 48-inch pipe for its water. Time to diversify | Opinion
Most of Folsom sits south of the American River and relies on a single 48-inch water pipe, starting in the heart of the nearby dam, to survive.
This pipe was plenty big and reliable when it was built along with the Folsom Dam in 1955, when the city was home to all of 2,000-some residents. But now with a booming city of more than 80,000 thirsty locals, Folsom is wisely looking to somehow diversify its water plumbing and portfolio.
After a years-long process known as the Folsom Water Vision that engaged its active citizenry to search for new supplies and ways to ensure water taps never run dry, Folsom has found its most important solution. It’s not a new supply from elsewhere. It’s from the same American River, just with another pipe downstream.
In water, redundancy is a wonderful thing. It’s particularly needed for Folsom because if droughts deepen and the dam empties, that 48-inch pipe will run dry.
“You potentially have times when it may be drier,” said Marcus Yasutake, Folsom’s water director and 20-year employee.
Shades of Las Vegas
Folsom is hardly the first growing city in the West to study alternative water supplies because it is disadvantaged by geography and confined to a single supply. The most spectacular example is greater Las Vegas.
For years, the famous Sin City pursued a pipeline to the northern reaches of Nevada to reduce its dependency on Lake Mead behind Hoover Dam. Instead, the region abandoned this second supply and doubled down on the Colorado River. Now constructed is a new pipeline that reaches the very bottom of the lake.
The Folsom Water Vision settled on quite a similar approach, proposing a new water intake at the regulating reservoir just downstream of Folsom Dam, in Lake Natoma behind Nimbus Dam. Even at exceedingly low water elevations, the river outlets on Folsom Dam can release water into Lake Natoma. It’s the perfect spot for that second pipe.
When Folsom gave up on a second supply
Folsom should have secured a second water supply by now, but plans over the years changed.
When Folsom voters in 2004 approved all that growth now happening south of Highway 50, Measure W also promised a “new” water supply. For years, one candidate for this new water was the Sacramento River, via a sale from the Natomas Mutual Water Company, as studied by county officials.
But piping all that water from Sacramento for 11,000 new homes was going to be expensive. And meanwhile, Folsom, to be blunt, stopped wasting water and had some to spare.
The advent of water meters starting in 2007 and calls to conserve during droughts caused water use in Folsom to plummet from about 400 gallons per person daily to something closer to 220 gallons today, according to Yasutake.
Folsom officials then came up with the idea that the “new” water for development south of the highway was water conserved by lower use to 50’s north. This rationale passed muster in a court proceeding, but some long-timers in Folsom living north of the highway still don’t buy it.
Sentiment of fellow residents north of the highway is “the south of 50 plan essentially stole water from this side of the town,” said Councilwoman Barbara Leary. “I don’t think the people south of 50 understand that sentiment.”
The search for a truly new supply continues. Some neighboring water districts have been looking for ways to store more groundwater as a hedge against droughts. Folsom is physically tied to the San Juan Water District to the north via a pipe on Rainbow Bridge and with a connection to the south with the Golden State Water Company, which serves Rancho Cordova.
Managing surface and groundwater supplies in harmony in a manner that maximizes the stored groundwater is something called conjunctive use. And for now, that’s simply not in Folsom’s water vocabulary. Yasutake is trying to change that through new regional partnerships.
“Figuring out how Folsom connects into the conjunctive use world is critical for us,” he said. He’s right. Even with a second American River intake, a true second supply makes a world of sense.
Progress on water takes time. It will take years, in the best scenario, for Folsom to have a second American River intake and not depend so exclusively on that 48-inch pipe originating in Folsom Dam. But the city deserves credit for thinking long and hard about its water future. That’s how progress starts.
This story was originally published February 6, 2026 at 5:00 AM.