Point Reyes Light - January 5, 2005
Reservoirs full but spring rain needed
By Jim Kravets
Reservoirs in West Marin are brimming with rainwater, but the water districts caution that the recent deluge doesn’t necessarily mean water needs will be met for 2005. More than 24 inches of rain fell on the western slopes of Mount Tamalpais during the month of December, bringing the total rainfall there to 43 inches since September. Last month, Mount Barnabe, above Lagunitas, received just over 11 inches, while the rain gauge at Muir Beach collected eight inches during the same period. The average rainfall for weather stations in West Marin during December was 11 inches, just ahead of the historical average.
The eight water districts and service providers in West Marin rely almost entirely on winter rains to refortify the various wells, aquifers, creeks, and reservoirs which feed their systems. Heavy early season rains are good news for districts like Marin Municipal, which – with seven reservoirs – has a large storage capacity.
Inverness
Inverness, by contrast, has no ability to store untreated water and depends exclusively on a steady, year-long supply from the springs, creeks and seeps of the Inverness Ridge watershed area. One stream, First Valley Creek, provides the town with most of its water.
"We don’t have reservoirs, so we’re hand-to-mouth with water supply," said Jim Fox, who supervises the water supply for Inverness Public Utility District.
IPUD owns 10 storage tanks throughout the town which holds a little more than 325,000 gallons of treated water.
"Spring rains definitely help us. We’re looking pretty good right now," added Fox who is also the town’s firechief. So far, Inverness has recorded about 16 inches of rain since July. The town’s yearly average, since 1925, is about 38 inches, leaving the community an inch and a half over last year, Fox noted.
Stinson Beach
Stinson Beach also relies on surface water, but the town water district owns two storage tanks for untreated water which hold 610,000 gallons – not nearly enough, according to Stinson Beach County Water District Manager Richard Dinges.
"We have very little reserve," Dinges said. "Our storage is mostly treated water. We’re not ready for summer. We need the rains to continue throughout the spring."
He said that early rains help replenish the town’s deeper aquifers – some as deep as 270 feet, but, "it can take three to six months [for rainwater] to seep that far," he said.
The district owns five tanks for treated water on the hill above town which hold 1.2 million gallons.
"They’re at about 95 percent capacity now," Dinges said. The district plans to complete refurbishment of a well at Alder Grove this month. The 1956-era well hasn’t been revamped for nearly thirty years, Dinges said.
Marin Municipal
Marin Municipal Water District, which supplies the San Geronimo Valley, is running 31 percent above its average untreated water storage capacity for this time of year, said spokeswoman Libby Pischel. The district’s seven lakes can hold a walloping 26 billion gallons with the two West Marin reservoirs – Nicasio and Soulajule – providing 40 percent of that amount. Currently the district lakes are 92 percent full. Usually, at the beginning of January the lakes are about 70 percent full, Pischel said. The lakes have reached full capacity in all but two years since 1992, she added, and the district expects the lakes to fill in 2005.
North Marin
"Stafford Lake is full," happily reports North Marin Water District Manager Chris DeGabriele. The Novato lake is that district’s only reservoir for untreated water. DeGabriele said that while the district breathes a sigh of relief in full rainfall years, conservation measures are still critical.
North Marin, based in Novato, supplies water to Point Reyes Station, Inverness Park, and other satellite systems in West Marin.
"Spring rains are still important. People should definitely use water wisely," DeGabriele said. This spring, the district will send notices to residents and businesses stressing the need to conserve water, he said.
Bolinas
Bolinas’ untreated water storage is only 0.05 percent that of Marin Municipal’s. The combined volume of the town’s two Mesa Road reservoirs, Woodrat 1 and 2, is only 13 million gallons, and they’re already brimming, Bolinas Public Utility District Manager Philip Buchanan reported. "Woodrat 1 started spilling over last week, and [Woodrat 2] has about six inches to go before it spills over," he said.
"It’s looking real good so far," Buchanan said, adding that "everything looked good last year too," when rainfall amounts were healthy in winter, but were followed by a relatively dry spring. Bolinas was forced to dig deep into reserves in order to survive the summer.
"The most important thing to us is significant late winter and early spring rainfall," Buchanan said. "That makes the biggest difference whether we can make it through the summer. Rains into April and May dampen everyone’s garden so they won’t need to irrigate early."
The district owns two tanks for treated water which together hold about 840,000 gallons, equivalent to a week in winter, or four days in summer, when water-use is higher.
Spring rains due
"We’re expecting this year to be at least normal if not above normal for rainfall," Bob Benjamin, a meteorologist for the National Weather Service office in San Francisco told The Light. "This means we’ll probably still get some fairly strong rains as well as dry periods. But overall, we might end up a little above the curve."
Oceana Marin
Late-season rains are really the only rains that matter for Oceana Marin in Dillon Beach. The 128-house subdivision’s untreated-water reservoir can hold 13 million gallons, but it currently lags behind others in West Marin being only 65 percent filled.
The reason, explains, John Brezina, a marine biologist who runs the subdivision’s water system parttime, is that the reservoir is filled from ravines via pump, not rain. What’s more, the company hasn’t even started pumping yet.
"We usually only pump in springtime," said Brezina. "The first rains of fall and winter are dirty, filled with organic matter. We don’t want that in the reservoir. We don’t start pumping until later this month." As a result, he said, the reservoir doesn’t always fill.
"Seventy percent of the years we can get it filled," he said.
Dillon Beach
In stark contrast, other residents in Dillon Beach receive their water from the San Jose-based California Water Service Company ("Cal Water"), the largest publicly-traded water utility in the Western U.S., which serves more than 500,000 households statewide. Cal Water took over the remains of the former Coast Springs Water Company in early 2000. The company has no reservoirs for untreated water and obtains 75 percent of its water from Dillon Creek. The rest comes from low-producing wells on the ridge above town.
Bill Koehler manages Cal Water’s Redwood Valley District which includes 260 homes in Dillon Beach. Koehler said December’s rains help swell underground aquifers.
"The more saturated the ground is," he said, "the longer it will release water later in the season."
Koehler said the company plans to build a new water-treatment plant on the same site as the current facility. Construction is scheduled to begin in the spring and the plant should be operating by the end of 2005, he said. Koehler hopes the new plant will allow Cal Water to take on new customers. "There’s a waiting list of about 20 undeveloped parcels."
Cal Water owns one 210,000 gallon storage tank for treated water which is currently filled. Koehler said the company is also finishing up construction of a new, 120,000 gallon storage tank for treated water. "It should be finished in about a month," he said. "It has a porcelain finish inside and out, like a cast iron bathtub."