With an assessment approved to pay for the design and expansion of a recycled water pipeline to the Carneros area, some grapegrowers are pushing for a change in state law that would make it easier to store that water in some local reservoirs.
Landowners approved the $100-per-acre assessment in March, which will contribute $1.3 million over the next three years to design the infrastructure and expand the pipe to 24 inches in diameter.
The pipeline would run from the Napa Sanitation District’s plant on the east banks of the Napa River, under the river to the Stanly Ranch property and then out to the Carneros region.
The Los Carneros Water District has a will-serve letter stipulating delivery of 1,250 acre-feet of recycled water when the pipeline is constructed. Another assessment — estimated to cost $4,200 per acre — will be needed to finance the pipeline’s construction, which is estimated to cost about $16 million total.
Water District Board President John Stewart said Friday that a change in state water regulations is needed to make it easier to store recycled water in on-stream reservoirs. Stewart said the Carneros area has some small- and large-sized reservoirs, while other property owners don’t have any.
Jim Lincoln, vineyard manager for Beckstoffer Vineyards, said the majority of the reservoirs in the Carneros area are on-stream, and state law stipulates that recycled water can’t be stored in these kinds of reservoirs.
“Right now it’s not allowed,” Lincoln said. “It’s not allowed to be put in anything that’s an on-stream pond.”
Stewart, in a letter requesting the recycled water from the Napa Sanitation District, notes that some of these reservoirs can be converted to off-stream, which are allowed to store recycled water. He said a better solution is to allow recycled-water users to develop water management plans for storing it in on-stream reservoirs.
The idea is to give growers protection in storing this water, in case a late winter storm blew through and caused the ponds to over flow, spilling recycled water. The Los Carneros Water District would receive 850 acre-feet of recycled water in the wintertime.
Lincoln said changing the regulations would give the water district more flexibility in managing water usage. He noted that the Napa Sanitation District is allowed to discharge secondary treated water — a lower quality than the Los Carneros Water District would get — into the Napa River during high-flow periods, when it’s diluted.
“It would just add flexibility to the system and add storage capacity to the system,” Lincoln said.
A bill in the California Legislature from Assemblyman Marc Levine, D-San Rafael, would help to expand the use of recycled water, and Stewart said he hopes to get Napa County’s representative in the state Senate, Sen. Lois Wolk, D-Davis, on board as an advocate.
The bill would create a pilot program in the San Pablo Bay area that would demonstrate the effects of storing recycled water in this fashion, said Ann Dubay, a spokeswoman for the Sonoma County Water Agency, which is supporting the legislation.
She described the reservoirs as seasonal ditches, and said the intent is to have the project include several growers by next winter to measure any effects storing the recycled water could have on water quality. She said supplementing these supplies to irrigators will reduce the stress on groundwater supplies in some parts of the North Bay Area.
“We would like to have more of that water in storage so farmers can use it in the summer,” DuBay said. “We have a lot of demand for that recycled water. I think there’s the possibility we could show that recycled water could be a beneficial use.”