Should 2008 continue this year's pattern as a critically dry year, growers served by the Merced Irrigation District are looking at the possibility their normal water deliveries will be halved as well as the prospect of groundwater pumping to satisfy demands.
Mother Nature's capricious precipitation tendencies are always up in the air, but the National Weather Service is couching its rainfall bets for the next 90 days, saying there is an even chance of above-normal rain -- or below-normal rain.
The parched prognosis is all the more reason for the entire community to come together for a discussion of long-term solutions for a stable, adequate water supply, Diana Westmoreland Pedrozo, Merced County Farm Bureau executive director, said.
Ted Selb, MID deputy general manager, presented water directors with two scenarios for planning purposes this week, one assuming 88 percent of average water supply and the other assuming another critically dry year like this year, with rainfall 35 percent of average.
If this one comes to pass, in-district growers could be looking at getting 50 percent of normal surface water deliveries, the necessity of pumping 95,000 acre-feet of groundwater and a water season cutoff as early as Sept. 15. This year's irrigation season was ended at the end of September, a month earlier than normal, due to a sparse water storage picture.
Westmoreland Pedrozo voiced the farmer's familiar lament.
"Water is our lifeblood. Every year it's a gamble we will have rain or not. We have a very complex water system and need to manage it much better fashion than we have in the past. Water is such an important issue, everybody has a stake in this issue," Westmoreland Pedrozo said.
Selb said the board authorized a $3.75 million transfer from the U.S. Bureau of Reclamation that could pay for two years of groundwater pumping and save growers from paying sizable pumping surcharges. Board Vice President Tim Pellissier said pumping could have cost growers an additional $12 a foot without the Bureau of Reclamation transfer.
Michael Bingham, meteorologist at the National Weather Service office in Hanford, said a La Nina weather pattern, the opposite of an El Nino one, is developing. With La Nina, the storms that form go to the Pacific Northwest rather than shifting to California.
October is typically a dry month and November to December are wetter, averaging a couple of inches of precipitation. January is typically the wettest month of the year, Bingham said.
Westmoreland Pedrozo said those with access to wells will have to pump water. She said water is not just an agriculture or a city issue.
"We will survive but at what cost? Now's the time to talk about it since it's on everybody's radar. Surface water is not just for ag, it's for environment, recreation, power and food production. MID has led the way in promoting conjunctive water use with the city of Merced but they can't do it alone," Westmoreland Pedrozo said.
Pellissier said the district has been in worse situations in past years. Some almond growers were polled about the early irrigation cutoff and found most growers have access to wells and there wouldn't be much hardship.
"We've been through these types of years before. If we have another water year like this year we'll have to cut deliveries in half. The pumping cost is pretty substantial," Pellissier said.
Selb said the MID's budget goal for the 2007 irrigation season was to sell 310,000 acre-feet of water, assuming an Oct. 31 cutoff. Even with an early end to the season, the district sold 303,200 acre-feet of water, something Selb calls an amazing feat. Without an early cut-off, the district might have sold 330,000 acre-feet of water this year.
As of Oct. 15, water storage at Lake McClure, behind Exchequer Reservoir, stood at 322,000 acre-feet of water, 32 percent of capacity and 64 percent of the long-term average, Selb said.
MID is releasing 18,000 acre-feet of water this month to satisfy minimum fish flows for fall run chinook salmon and will be releasing 30,000 acre-feet in November and 20,000 acre-feet in December, Selb said.
Maxwell Norton, Merced County farm adviser with UC Cooperative Extension, said groundwater pumping is a big concern and will come at great cost to farmers and society in general. He said groundwater quality declines as there is more overdrafting. Salinity levels have steadily increased in groundwater over the years.
"In some areas of the county, groundwater is very expensive to pump. The deeper the water, the more expensive it is to pump. Many growers will curtail certain crops next year since they won't have enough water, especially on the Westside," Norton said.
With the critical water year scenario, Selb said the peak in Exchequer water storage would be 400,000 acre-feet at the end of May, with the reservoir drawn down to 300,000 acre-feet in September. It will cost $1.9 million to pump 9,500 acre-feet of water.
The second water scenario with 88 percent of average, Selb said, projects close to normal water levels, with a peak Exchequer storage at the end of June of 680,000 acre-feet of water, or 68 percent of the reservoir's capacity. There would be no surface water curtailments and the season would end Oct. 31 with 400,000 acre-feet of water in storage.
An acre-foot of water is the amount of water needed to cover an acre, one foot deep in water.
"It is so early in the season these are really outlooks rather than actual forecasts. Snow surveys don't start until Feb. 1. We assume the worst and hope for the best. From the district's perspective, until we see snowpack figures, growers need to prepare for curtailment. There's no choice," Selb said.
If it's any consolation, Bingham, the weatherman, said, this area isn't hurting nearly as bad as other parts of the country, such as the East Coast and Southeast, which are in the midst of a severe drought.
The three to five-month National Weather Service outlook, through February, shows above-normal temperatures and below-normal rainfall," Bingham said.
Westmoreland Pedrozo said counties, cities and irrigation districts need to look for long-term solutions for a stable water supply.
"The million-dollar question is how much drawing down of the water table can you do. We really don't know. It all starts adding up. We're overbuilt and need to look at development that is more efficient. The city of Merced is the only one on water conservation; the rest of the cities could follow suit," Westmoreland Pedrozo said.
Associate Editor Doane Yawger can be reached at 209-385-2485 or firstname.lastname@example.org.