It's been a dry year. The lack of rain and mountain snow is now a serious concern, not just for our agricultural economy, but for all who live in Central California.
This time last year we had nearly a foot of rain. As of late February, we have less than three and a half inches. The current 30% snowpack is even more concerning because it feeds our water supply the rest of the year.
To understand why this year is so dry, meteorologists look to the past for patterns going back months, decades, and even centuries.
CBS47’s Chief Meteorologist Scott Mace said, “You have this strong La Niña pattern that is forecast to weaken.”
To explain La Niña, meteorologists look to the jet stream. In general, storm systems follow this path as they gather water from the Pacific and drop it on land. The jet stream is always moving. It cycles up and down, some storms hitting farther north and south. All the storm tracks average-out over a season, with the greatest rain and snow falling right in the middle of where the jet stream flows.
However, La Niña and El Niño marked by changes in ocean water temperature, influence this average position of the jet stream, and where storm systems bring water, or in the case of this La Niña, don't bring water.
It doesn’t always work out that way. Last year was far from average. A prominent La Niña with one storm after another.
Mountain snow melts in spring, summer and even fall, filling creeks, then streams, then the rivers and lakes that bring water to the Valley.
Snowpack powers our homes, too. Construction on the Big Creek System began one hundred years ago. The dams generate electricity, prevent floods and store water for dry years.
But there isn't enough space in all of California's lakes and reservoirs to save water very long. This dry La Niña year will likely drain away every extra drop from last year.
Randy McFarland's work with the Kings River Water Association and Friant Water Authority has shown him the importance of storage and conservation. "Capture as much of that as we can, get as much of it in the ground as we can, store as much as we can through all the tools that we have in order to maximize our water supply in the long run," said McFarland.
Although this winter is dry, stored water from last year is quite high at places like Millerton Lake. "…the highest amount of carryover storage that the Friant Division of the Central Valley Project has ever had," said McFarland.
It is good news, but low levels at Lake Shasta in Northern California can quickly cancel out a Millerton surplus when the two waters meet in the San Joaquin delta. Delta water amounts determine allocations to farmers and decisions are made on the federal level.
Gayle Holman with the Westlands Water District said, “The difficulty is that planting season has already begun. Farmers have had to plan out what crops they're going to grow. If there isn't a high water allocation available for growers, that natural rainfall occurring, they may not be able to use some of the crops that they planted."
Methods are different at each of the dozens of water districts that serve our area. On the east side, the source may be the King's River with storage at Pine Flat Lake. "Pine Flat actually operates like a series of bank accounts. When you look at Pine Flat Reservoir think of it as 28 different reservoirs because each of the 28 different units of the Kings River Water Association determines if they want to store water or release water, and if they release enough of it and they run out of water -- well it's like my bank account -- if I don't have any money, I can't spend it," said McFarland.
Meteorologist Justin Sacher visited the Kings River, to the area where it comes out of the mountains. Part of the flow is diverted into the Fresno Canal for water use in the Fresno area. Part of it is also diverted to the Consolidated Canal, where water is used in areas like Sanger and Caruthers. And some of the Kings River continues to flow onto parts of Western Fresno County and Kings County.
Almond trees on Paul Betancourt's farm get water from the Fresno Irrigation District. He knows there's enough water stored to make it through this year… but not next. “If it doesn't rain next year, we're going to be having an entirely different conversation. It will be all-hands-on-deck, battle stations; don't water your lawn type drought.”
Although a "March Miracle" is possible, the best chance for more rain and snow comes not next month, but next year.
Dr. John Christy said, "The snow goes up and down from year to year but overall there's no long-term trend."
Dr. Christy is the Director of the Earth Science System Research Center at the University of Alabama and just published some of the most comprehensive research on California snow. He's an expert on climatology and a Fresno native. “I graduated from Hoover High and Fresno City and Fresno State College… they just changed it to University, Fresno State University when I graduated.
Dr Christy's research brought him to previously unstudied mountain snow records more than a hundred years old. The Southern Pacific Railroad needed to know what their trains were going to experience when they sent them over the Sierra crest, so they had operators at these stations up high in the mountains that would measure the snow every day and reported back by telegraph what the amounts were so the train stations would know whether to send the train or not,” said Dr. Christy.
And although Dr. Christy's research shows stretches of very wet and dry years, including serious droughts, come and go over time, Central California is not becoming drier in the long run. The data shows, snowy winters have always come to even things out.
Meteorologist Scott Mace said, "It doesn't make it any easier when farmers have to deal with dry years and drought conditions and part of that comes from water storage. But it will always come back in some form whether or not we have El Niño or La Niña or a typical year, we'll get that water back eventually.”
Randy McFarland said, “As serious as it seems it is not necessarily going to be the worst water year we've ever had. It's been tough before and we've learned to use water wisely and understand we can't conserve our way out of a drought."
