Editor’s note: This is the first in a series of stories about the water supply in the Valley.
With the demand for water increasing and the fluid water supply, the Sonoma County Water Agency and its partners are currently working on a five-year review to revisit and revise its strategies to better manage water and create more effective systems.
The SCWA, which is based in Santa Rosa, was created in 1949 as a special district by the state legislature to provide flood protection and water supply services. In 1995, the water agency was tasked with additional responsibilities of water sanitation and wastewater disposal. The Sonoma County Board of Supervisors acts as the agency’s board of directors, but since the agency was created through state law with a specific mission and powers, it is recognized as its own entity and receives separate funding. The agency sells water in Sonoma and Marin counties and has 4,383 water service connections (meters) and 49 miles of water main. The agency manages six water tanks, two of which it owns, with the storage capacity of 15.5 million gallons. It also has seven wells, with four of them fully active.
But managing the water supply in the Valley is not so simple, SCWA Chief Engineer Jay Jasperse said.
Each variable affects the water supply, Jasperse said, noting the interconnectivity and the difficulty this poses in creating a plan to be prepared for a shortage or a surplus of water.
Jasperse said while the state of water is not certain, Sonoma County “will have water, but (SCWA) wants to be efficient with it.”
The challenge, Jasperse said, is that water management is a constant battle with Mother Nature to create systems and test “how (SCWA’s) systems deal with the variables.” The water agency, therefore, errs on cautious side to prepare for worst-case scenarios. As winter approaches, Jasperse said, he will “assume until proven otherwise that it is going to be dry.”
The water agency has two reservoirs – Lake Sonoma, west of Healdsburg in the northern area of the county, and Lake Mendocino, northeast of Ukiah. Lake Mendocino, which flows into and out of the Russian River, is continuously problematic, Jasperse notes. Right now it is at 30 percent of its capacity because of a dry year.
The City of Sonoma is affected by the problems at Lake Mendocino, Jasperse explained, with the most impact from the depleting reservoir being felt in Ukiah.
On the other hand, Lake Sonoma, which flows into and out of Dry Creek, Jasperse said, has about a three-year carry over and is where the agency gets most of the water for its retail circulation.
The releases from Lake Sonoma were too high in the summer, with the high velocity proving damaging to the surrounding habitats of protected fish (coho and chinook salmon and steelhead) species. The water agency must lower not only the velocity of its flow, but also reduce the amount of times it releases water from it reservoirs by 2023, Jasperse explained. It is currently working on a restoration project in Dry Creek to handle water in a more fish-friendly way. Jasperse said the project aims to create pockets in the waterway with small alcoves where the fish can swim to the side and avoid rapid flows. The key, according to Jasperse, is finding a balance of holding enough water for a good supply and releasing enough water from the reservoirs so that, in the event of a storm, floods are prevented.