Is it sustainable for Sonoma County to build new homes during an ongoing water crisis?
Starting in 2023, the state wants Sonoma County to approve over 14,500 new homes for residents of all income levels over the following eight years.
Though no final target has been approved, officials in some of the county’s largest cities have made ramping up home construction a priority with the goal of alleviating the region’s shortage of affordable housing.
At the same time, though, the state is also mandating water cutbacks across the region during what is shaping up to be the worst local drought in more than four decades.
The two seemingly competing mandates have some questioning the wisdom of continuing to push growth in the face of a water crisis.
“How are we still approving new development in the midst of a two-year drought with no idea what's going to happen next year?” said David Keller, a Petaluma resident and Bay Area director of Friends of Eel River, a Eureka-based environmental advocacy group.
Sonoma County residents posed similar questions to The Press Democrat as part of its North Bay Q&A series, which collects and answers readers’ questions about life in the region.
Municipal planners and local officials answer that they’ve carefully considered the area’s expected water supply over the next few decades and are confident it will be enough to meet demand, even when sustained dry years are taken into account.
They contend that conservation efforts, which have significantly reduced per-person consumption, will help ensure that the region’s reservoirs, wells and underground aquifers can provide the necessary water even as more people move to the area.
“Ongoing conservation has just overwhelmed population growth, and our overall water consumption continues on a steady downward trend,” said Petaluma City Councilman Mike Healy, a former chair of the advisory committee to Sonoma Water, the region’s primary water management agency.
That doesn’t change the fact that Lake Sonoma and Lake Mendocino — local cities’ main water sources via the Russian River — are currently approaching record lows. As a result, the state ordered water cutbacks, pushing most of the county’s cities to issue mandatory water reductions of between 20% and 40%.
In light of the severe shortages, conservationists are skeptical of officials’ projections about future water supplies. They argue the state and local municipalities should reconsider whether the region’s water systems can support substantially more homes.
Rue Furch, an environmental advocate and former member of the Sonoma County Planning Commission, said there are many unknowns about the region’s water supply beyond just the impacts of climate change. That includes exactly how much is held in the county’s groundwater reserves and who will eventually take over the aging PG&E-owned Potter Valley Project, which diverts billions of gallons of water each year from the Eel River to Lake Mendocino.
“While jurisdictions are being really mindful of water use, the uncertainty of water availability makes it hard to definitively say, ‘of course we can build more,’” she said.
Local officials say they are confident the county’s water supplies can support continued growth. Under state law, all urban water suppliers are required to create detailed management plans every five years to outline how current and future water demands will be met.
The county’s three largest cities — Santa Rosa, Petaluma and Rohnert Park — each create their own plans to determine how much water they need for at least the next 20 years. The documents must take into account climate change, expected population growth and housing development, among other factors.
Sonoma Water in turn uses those plans to create its own water management plan for urban areas in the region. By 2045, annual demand from the agency’s eight water contractors in Sonoma and Marin counties is estimated to reach more than 24 billion gallons of water, a 41% increase from 2020.
Paul Piazza, a Sonoma Water manager who helped draft the agency’s most recent plan, said currently available water resources should be enough to cover that increase under most future environmental conditions.
To predict the impact of climate change on the long-term water supplies, the agency collaborates with researchers from the National Oceanic and Atmospheric Administration and scientific nonprofits, Piazza said. He added that if extreme drought scenarios are found to be more likely, Sonoma Water will update its plan and work to identify additional water supplies.
“This is an exercise that we revisit on a five-year cycle because of the fact that things change,” Piazza said.