FAIRFIELD — Rain season 2013-14 is here, with plenty of implications for Solano County.
Powerful rainstorms hitting often would push up the water supply in Lake Berryessa reservoir for local cities and farms. Plenty of snow in the Sierra Nevada would boost the Sacramento-San Joaquin Delta water supplies for local cities.
Then again, a relatively dry year would allow construction projects to get done sooner, such as the effort to widen Highway 12 in Jameson Canyon to four lanes. Planned construction next year to renovate the Green Valley interchange might get started earlier.
Viewed that way, either rain year scenario could be a glass half-full.
But Solano County is coming off a drought year. The rain season that began in July 2012 and ended in June 2013 brought only about 13 inches to Fairfield at Travis Air Force Base, compared to the usual 20 or so inches. Resident Fred Barnes measured only about 16 inches at his home in northeast Fairfield.
Given that, another drought year could be a glass half-empty for the region’s water supplies – or worse.
No one can know for certain what rain year 2013-14 will bring, anymore than they can know which team will win the Super Bowl. But, in either case, people can make educated – and uneducated – guesses. Humankind has been trying to predict the outcome of upcoming rain seasons for centuries.
Mike Pechner is a Cordelia Villages resident and owns Golden West Meteorology. He and other weather experts making long-range forecasts look at Pacific Ocean temperatures for El Niño or La Niña conditions that can influence the weather. For example, El Niño conditions historically often lead to big rainfall years.
“It’s a La Nada year,” Pechner said. “Neither El Niño or La Niña.”
Pechner expects that Solano County will have near-average rainfall this rain year, between 90 and 110 percent of normal. Possible El Niño conditions in March, April and May could lead to a wet spring, he said.
This rain season won’t be a major recovery, but it will be enough to keep the region from being in deep trouble, Pechner said.
The National Weather Service puts out long-range forecasts. But its precipitation forecast maps through June 2014 indicate nothing conclusive for Solano County, just an equal chance that rain could be above normal, below normal or normal.
The Old Farmer’s Almanac is bolder. Ever since 1772, the almanac has made its predictions, initially with a secret formula that the almanac says is kept in a black, tin box at its New Hampshire headquarters.
“Winter will be much rainier and cooler than normal, with mountain snowfall much greater than normal,” the Old Farmer’s Almanac predicts for Northern California. “Most of the rain, snow and storminess will come in January and February, when storm damage will be a concern.”
If the Old Farmer’s Almanac is correct, this winter will mark a major turnabout from recent ones. Though it’s true that January is usually the wettest month of the year in Solano County, the past three Januarys have been just about dry.
Rain sounds like good news to local water managers. Even so, they don’t see an immediate water crisis.
Lake Berryessa reservoir in Napa County is at 71 percent capacity. It is holding 1.13 million acre feet of water and has a capacity of 1.6 million acre feet. According to the Metropolitan Water District of California, an acre-foot is enough water to serve two average families for a year.
“Right now, it’s about a low as it’s going to get,” Solano County Water Agency Manager David Okita said. “It will go up once it starts raining.”
Okita said he’s heard of no major weather patterns, such as El Niño, that indicate what the upcoming rain season will hold.
“Absent that, I never even look at the long-range forecasts, because they’re never accurate,” Okita said.
Lake Berryessa gets its water from rain-fed creeks and streams draining a watershed that extends to Mount Cobb in Lake County. The reservoir is slow to empty, but also slow to fill. It last topped its Glory Hole spillway in 2006 and this year reached 86 percent of capacity, before the summer drawdown.
If this is a normal rainfall year, Lake Berryessa will not fill, Okita said. In fact, once the lake has peaked and gone through the summer drawdown, it would end up in October 2014 at the same level it is at now.
“An average year, you run in place,” Okita said. “What you do is you hope for a wet year and that allows you to have several dry years.”
Every now and then, an extremely wet year comes along, such as 1994-95. Lake Berryessa began that year with only 550 acre feet of water, far short of its 1.6 million acre-foot capacity. It added almost 1 million acre feet in a rainy season that saw Fairfield get about 34 inches of rain.
The Fairfield Public Works Department is getting ready for the rainy season. That means doing such things as sucking leaves out of storm drains with vacuum trucks and making certain creeks can flow without backups.
But the city can’t do all of the preparation work that public works officials think is needed. They would like to dredge Jameson Canyon Creek and American Canyon Creek in the Cordelia Villages area. But they must first get the necessary permits from the state Department of Fish and Wildlife.
“It’s an exhausting process,” city Landscape Maintenance Manager Mike Gray said.
Silt gets carried from nearby hills in the creeks and piles up in the lower channels, blocking storm drainage outlets from the subdivisions, Public Works Director George Hicks said. Silt builds up in the pipes and plugs them, he said. Big storms hitting when the ground is saturated could send silt and mud backing up onto some streets.
“It’s heavy enough where it’s hard to recognize it’s a street, for all the silt,” Hicks said. “I wouldn’t say it puts homes at risk, but the public convenience is at risk.”
That hasn’t happened in years. But American Canyon Creek overflowed during the New Year’s Eve storm in late 2005 and early 2006, sending water on streets. That particular storm was among the biggest in recent decades, dropping 4 to 6 inches of rain within 24 hours in some parts of Solano County. Flooding caused problems in various parts of Fairfield and Vacaville.
Fairfield last dredged Jameson Canyon Creek and American Canyon Creek in 2010, though the city’s environmental permit was for less work than public works wanted to do. The silt quickly returned.
“The work we had done, you couldn’t even tell it was performed after that one season,” Gray said.
The answer may be in sight. The Habitat Conservation Plan being worked on by the Solano County Water Agency could be completed next year as a big-picture look at the county’s rare species situation. Among other things, a plan approved by the U.S. Fish and Wildlife Service and state Department of Fish and Wildlife would make it easier for Fairfield to do dredging maintenance work in creeks.
Farmers also look ahead to the rainy season. Solano County is home to dozens of crops, from grapes to alfalfa to pears to tomatoes to walnuts to nursery stock. Agricultural production in 2012 was worth $342 million, according to the county crop report.
County Agricultural Commissioner Jim Allan said that, from a farming perspective, cold, wet winters are the best. That gives the necessary chill hours for some plants and synchronizes the bloom, he said.
But no one gets to order what the rain season will be like. All one can do at this point is make predictions and then wait to see what happens.
Reach Barry Eberling at 427-6929 or email@example.com. Follow him on Twitter at www.twitter.com/beberlingdr.
When the Storm Hits
The Solano County Water Agency provides flood forecasts when storms are predicted to hit, as well as shows the levels in local lakes and creeks. Go to www.scwa2.com and go to the “flood control” to get this information.
Fairfield rain statistics
Here are the rainfall totals in Fairfield in recent years, as recorded at Travis Air Force Base: