Raul Ramirez of Bubba’s Truck Service delivers water at a home in Madera. At least five communities in Madera County have had to rely on bottled or hauled-in water in recent years.

Many small and rural communities across California are vulnerable to drought and water shortages as they lack the diverse water sources and infrastructure of big cities like San Francisco and Los Angeles. In some cases, these communities are forced to rely on bottled water or water hauled in from elsewhere, which experts say is costly and unsustainable.

Data from the state water board’s 2022 “Drinking Water Needs Assessment” shows that nearly 90 water providers across the state, including six in the Bay Area, have had to resort to bottled or hauled-in water to fully meet their communities’ drinking water needs in the past three years. The report finds that California’s ongoing drought played a role in straining supply for some of these providers.

There are more than 7,000 water systems in California that provide water for people through pipes or other types of connections, and they vary in size, from those serving large cities to ones built for apartment complexes or single schools. All of the 89 systems shown as relying on bottled or hauled-in water in the 2022 assessment are smaller providers with fewer than 30,000 service connections. In comparison, the San Francisco Public Utilities Commission serves about 2.7 million customers.

The largest provider among the 89 was the City of Wasco, northwest of Bakersfield, which serves water to nearly 23,000 people. Thirty-two of the 89 providers are schools in small or rural communities, including Pope Elementary School in Napa, Mountain House School in Alameda and Pescadero High School in San Mateo County.

All of them are failing or at risk of failing the state’s safe drinking water standards, which are based on several factors, including water quality, accessibility and affordability.

Bringing in bottled or hauled-in water to meet demands, however, is only a temporary fix and should be a “last resort,” said Eric Zuniga, a drought response program manager for the drinking water division of the State Water Resources Control Board.

“The issue is that (bottled or hauled-in water) can’t be relied upon,” he said “There are so many things that can happen to an alternative water supply, which means a whole community or a household can run out of water,” he added.

Communities rely on bottled or hauled-in water for different reasons, he said. In many cases, it’s because their primary supply, such as wells, contain high levels of harmful chemicals. Others may be short on supply because of overdrafted aquifers and the ongoing impacts of drought.

One of the most important vulnerabilities that the vast majority of these 89 water systems share is that they have only one source of water, Zuniga said, many of them groundwater sources like wells. Cities like San Francisco, on the other hand, have many backups, including a water bank system to store excess water from wet years for use during dry ones.

Ten of the 89, most of them in drier Central or Southern California, have been specifically identified by the state as relying on bottled or hauled-in water because of adverse drought impacts. Much of the most severe and extreme drought conditions in the state have been in those areas, according to the U.S. Drought Monitor. All of them rely on some type of groundwater, the levels of which have been critically declining in recent years.

These 10 water systems are in some of the most disadvantaged and resource-starved areas of the state. The average median household income for people served by these water systems is just over $41,000, compared with the statewide median of nearly $79,000.

At-risk small and rural water systems have limited options — and money — for clean water, Zuniga said. They also don’t have the same planning and engineering resources as big agencies and cities do.

When the state identifies water systems as failing or at risk of failing, the state mobilizes state funding and staff resources to help them develop more sustainable ways of getting clean water, he added. That might mean helping build connections, such as pipelines, to bigger water infrastructure.

“Sometimes, it’s an easy project,” he said. “Nine times out of 10, it’s a difficult multi-year — decades, sometimes — project.”

Yoohyun Jung is a San Francisco Chronicle staff writer. Email: yoohyun.jung@sfchronicle.com

Yoohyun Jung is a data reporter for The San Francisco Chronicle. Most recently, she worked as a data journalist for Honolulu Civil Beat, a watchdog news organization covering the Hawaiian islands. Born in Seoul, Yoohyun began her career in Arizona, where she worked for two of the state's largest newspapers covering various beats, including criminal justice and education. She is also an alumna of Reveal from the Center for Investigative Reporting Investigative Fellowship and The New York Times Student Journalism Institute. 

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