1.4 Million Gallons an Acre Used by Tree Crops, per Year

AG Groundwater Use : 655 Billion Gallons a year in Madera County    (California)

By DJ Becker/ NewsMadera.com   August 15th, 2014

When almonds or other tree crops use at least 1.4 million gallons per acre each year, is there still any real doubt about where local groundwater is going ?

It’s an awkward and uncomfortable question posed in an agricultural community, especially when residents are being asked to conserve and see large new fields being ripped and prepared for fall planting.

Fallow fields now or epic fail later ?

In addition to failing residential wells, Madera crop fields could soon face fallowing or failure, if a better water balance isn’t achieved soon according to University of California, Central Valley water use expert and soils farm adviser Dan Monk.

And putting the brakes on AG use may be the only real solution, if the water tipping point hasn’t already been reached, according to Monk.

Other experts say once existing clay aquifers are drained they collapse, and are not able to be recharged – further complicating the underground water storage problems.

072514DJ dust bowl house

DJ Becker/NewsMadera.com   An occupied house is surrounded only by dust, near Avenue 21 in north Madera County. Occupants said their well produces barely enough water for inside use. Most 300 foot wells in the once nice area are faltering or going dry.

Many residents doubt the Madera County board of supervisors have the inclination or abilities necessary to stand up to powerful farming interests, who have already threatened legal action if their groundwater use is rationed or in anyway curtailed.

“The only way to achieve water balance now is to reduce the number of acres in production. Madera County is currently pumping more than can be sustained, creating long term water deficits,” and with nothing coming back in the result is widely declining water levels, Monk said.

Monk estimated that overall county water usage for Madera County agriculture at a staggering 655 billion gallons per year, with most if not all all pumped out from dwindling groundwater supplies this year. It’s a large, unusual and difficult computation, he said, but that’s billions, with a B.

Almonds and other permanent tree crops use approximately 52 inches of water in acre feet, which is around 1.42 million gallons per acre, per year, he said. Madera County has roughly 660,000 acres of tree and row crops under production in 2014. The drought has had an impact, Monk said, but the same industry that sustains the Central Valley – agriculture, is also the main user, or some would say abuser – of local groundwater.

Almond acreage in 2014 has also increased by at least 20,000 acres in Madera County, if not more, from the 2010 figures, according the farm report. Monk acknowledged the measurement of water use in Acre Feet and Acre Inches can be confusing unless someone works in agriculture. Critics say the AG measurements just camouflage the problem and sound innocent enough, until the calculations into gallons are made. By contrast residential usage is estimated to be only 4 percent of Madera County’s overall water usage, including the municipal use by cities.

Madera Irrigation District received a zero surface water allocation for irrigation from the state in 2014, according to MID president Carl Janzen and has been parceling out small amounts of water they had ‘banked’ or stored from previous years in local reservoirs like Friant and Hidden Lake, to some contract growers. Janzen said his own well has recently gone dry at 253 feet.

Residential wells going dry in the county are only the beginning, Monk said, bringing the obvious problem of groundwater overdrafting painfully home to many rural residents. “Wells are going dry all over the Central Valley. There’s no denying … the overdrafting now,” he said. Without recharge and sustainable groundwater, Madera farm fields will also falter and begin to fail like the west side of Fresno county, and other arid and barren counties to the south, Monk said. “Everything in this climate is irrigated in the Central Valley. Almost all of this water is pumped from groundwater, and in recent years there has been no recharge allocation.” he said. The existing water shortage is the direct result of years of unsustainable water use – over drafting by agricultural, and also the drought and climate cycles, he said. An acre of mature almond trees use approximately 52 inches of water per year, which translates into 1.42 million gallons per year per acre, Monk said. That amount is mainly what is used by the plant for production and evaporation, and little is recharged into the ground. By contrast grapes, cotton or other row crops use less, only about 28 inches per year. “Most valley crops are water intensive. Only alfalfa uses more water per acre, about 56 inches in acre feet, per acre per year,” Monk said. “Water use is moving in the wrong direction … in Madera and the Central Valley, and it’s had a large impact on groundwater. Madera has replaced lower water use crops like (grape) vines and cotton with higher water use crops .. but almonds make money,” Monk said. The lack of water has already forced the fallowing and removal of many irrigated fields relying on external water sources in western Fresno County. No groundwater is within reach on those dry fields, and other adjacent areas in the Valley could be next, he said. Monk said the ironically named Central Valley Project Improvement Act, or CVPIA, passed into law 8 or 9 years ago, also hasn’t improved the Central Valley’s water situation, but rather has had a large negative effect … by diverting most, if not all of Madera County’s potential surface irrigation supply and recharge water into the San Francisco Bay/Sacramento-San Joaquin Delta Estuary. Monk said it was a very complex situation but it was doubtful the groundwater could be recharged adequately anytime soon, given climate conditions, current levels of AG water use and the lack of state water allocation to replace what is used. That leaves only water use restrictions and or the fallowing of fields, and more resident’s wells potentially going dry, he said. “Recharge (of groundwater) is an answer but takes time and it’s better seen over a five year average. And recharge water and the purchase of water storage (land) isn’t cheap,” but the issue is urgent and needs to be addressed by local governments and irrigation districts, to stop the further groundwater decline, he said.

If the overdrafting continues, Monk said, it’s everyone’s problem,  livelihood and property that will soon be at risk.


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