Ramping Up Water Reuse
NORTH BAY: Agencies seeking $83 million to expand operations to help offset already strained supplies of drinking water due to drought
GUY KOVNER, Press Democrat, 5/18/22
Petaluma, one of the driest corners of Sonoma County during the past two years of drought, is making a multimillion- dollar advance into recycled water.
Operator of a wastewater treatment plant that serves about 65,000 people and treats about 5 million gallons of effluent a day, Petaluma is seeking grants for four projects with a total cost of $42 million.
Six other North Bay agencies — including Sonoma Water and the Sonoma Valley County Sanitation District — are proposing a dozen projects totaling $41.2 million, bringing the total to $83.2 million, as Gov. Gavin Newsom is backing water reuse as an antidote to drought.
The projects are meant to help offset already strained supplies of North Bay drinking water as California braces for longer and more severe periods of water scarcity amid the escalating climate crisis.
Through expanded treatment, new pipelines and storage facilities, the 16 projects are expected to deliver 5,364 acre feet of water per year — enough to offset potable
Billy Dixon, engineering technician with Sonoma Water, closes a valve April 29 at the new recycled water reservoirsupplies for about 32,000 people.
An acre foot is 326,000 gallons, about half the size of an Olympic swimming pool and enough for more than two households for a year.
“First and foremost is drought resistance,” said Christopher Bolt, Petaluma’s public works and utilities director.
“In the face of climate change we want to make sure we can meet the community’s needs.”
Water recycling — transforming sewage through intensive treatment into water safe for irrigation of landscapes, pastures, playgrounds and crops that are eaten raw — is a high priority throughout California in the third year of a drought that experts say could last another decade.
“Recycled water is a sustainable, nearly drought-proof supply when used efficiently, and the total volume of water California recycles today could triple in the next decade,” said the 2020 California Water Resilience Portfolio, a response to Newsom’s order calling for recommendations “to enable water security for all Californians.”
California produced 728,000 acre feet of recycled water in 2020, up about 40% from 20 years ago.
The State Water Resources Control Board is currently funding $970 million in loans and grants for 12 projects that would provide about 62,000 acre feet of recycled water per year for urban and agricultural irrigation and indirect potable use through groundwater recharge.
Wastewater experts like to say all water on, in and above Earth is recycled and humans are using the same water as the dinosaurs.
Petaluma’s Ellis Creek Water Reclamation Facility commits all treated water to irrigation of parks, schools, commercial properties, golf courses and farms during dry summer months, averting it from discharge into the nearby Petaluma River. In wet months, however, a substantial amount goes into the river, which is a tidal slough from San Pablo Bay.
“We’re looking to expand and grow the water recycling system,” Bolt said. “We have a vision of zero discharge into the river year-round.”
Expansion of the distribution system and developing more storage capacity would reduce the wintertime discharge, he said.
Petaluma’s rainfall to date for this year and 2021 is well below or only an inch above the level for the other 18 communities in The Press Democrat’s weather log.
Sonoma County Supervisor David Rabbitt, a Petaluma resident, is an avid booster of recycled water.
“My mantra is you gotta use water twice,” he said. “In an ideal world we would avoid using potable water for irrigation.”
Purple pipes that carry recycled water should go under every street in newly developed areas, along with power, sewer and regular water lines, Rabbitt said.
Rabbitt has served since 2013 as chair of the North Bay Water Reuse Authority, a collaboration of 11 agencies in portions of Sonoma, Napa and Marin counties dedicated to ending discharge of treated wastewater into San Pablo Bay, largely by diverting it to urban and agricultural irrigation.
The authority’s 350-square-mile territory faces “long-term challenges in providing reliable water supplies” with limited surface and groundwater sources and some groundwater basins “showing harmful effects on water levels and quality,” its website says.
“A warming climate will likely further stress water supplies, and recycled water is a sustainable resource that can help augment regional water supplies,” it says.
The authority’s first round of projects, started in 2012 and completed in 2020 at a cost of $104 million, is providing 3,800 acre feet per year for urban and agricultural irrigation along with 46 miles of new pipeline.
Sonoma Valley County Sanitation District’s projects included a fifth reservoir holding about 35 million gallons of recycled water and starting work on a 3.5-mile pipeline to carry up to 1,700 acre feet per year for habitat restoration at the Napa-Sonoma Marshes Wildlife Area on San Pablo Bay and along the Napa River.
Petaluma did not participate in the water reuse authority’s first round of projects, but has a fistful of major projects awaiting funding under the second round.
The projects, costing a total of $42 million, would yield a projected 2,575 acre feet of recycled water a year — enough to offset potable supplies for about 15,000 people.
Boosting the Ellis Creek facility’s treatment capacity would cost $9 million, while extension of the urban and agricultural recycled water pipelines would cost $33 million.
For Bolt, who came to Petaluma in September from Jackson County, west of Ann Arbor in southern Michigan, drought is a new experience.
Due to climate change and frequent precipitation, surface and groundwater levels have been rising in that area, with wet basements and routine flooding of streams and roadways, he said.
Bolt said he is impressed by water conservation efforts in Sonoma County, and in the regional authority as a “great example of how agencies can work together to solve pressing problems for the good of all concerned.”
The drought makes recycled water “even more appealing,” Rabbitt said. “It’s an easy sell because it makes more sense.”
Rabbitt said he was proud to have convinced Petaluma to join the North Bay regional authority “after they said no initially.”
Grant Davis, general manager of Sonoma Water, said the three-county authority is “a model for maximizing the benefits of limited water resources in the west.”
Projects can be designed to “meet the needs of entire watersheds,” he said, noting that federal and state funding agencies have policies that promote regional partnerships over independent jurisdictions.
California is developing regulations for direct potable use of recycled water, a system that puts it into public water supplies rather than limiting it to irrigation and injection into groundwater.
Orange County’s pioneering $481 million groundwater injection system, in operation since 2008, produces 100 million gallons of recycled, potable water per day through an advanced purification process that includes microfiltration, reverse osmosis and ultraviolet light with hydrogen peroxide.
Two-thirds of the treated water is piped to recharge basins in Anaheim, replenishing groundwater that provides 75% of the water for more than 2.5 million Orange County residents.
Davis and Rabbitt are not ready to advocate for direct potable use, also known as “toilet to tap,” a description some water experts find disagreeable.
Drinking recycled water “understandably triggers a gag reflex in some consumers — but it shouldn’t,” Amanda Little, a Vanderbilt University professor of journalism and science writing, wrote as a Bloomberg columnist.
“Recycled wastewater is quickly becoming the single most important element of a droughtproof water supply in the climate-change era, and it happens to be as pure and delicious as anything you might buy bottled from the Swiss Alps,” she said.
Rabbitt once tasted recycled water at a conference on water. “It was fine,” he said.
“Never say never,” Davis said.