Almonds could provide a solution to combat groundwater over drafting that is dropping a tenth of the San Joaquin Valley’s 10,000 square miles by an inch a year.
Scientists are conducting experiments to see if intentionally flooding almond orchards in winter with storm runoff delivered through irrigation canals can recharge aquifers.
If successful California’s largest agricultural export commodity could be harnessed to stabilize and start reversing what the U.S. Geological Survey has termed “the single largest human alteration of the Earth’s surface.”
The first massive sinking occurred in the mid-20th century when more than 5,200 square miles from south of Bakersfield to north of Mendota sank a foot. It is an area nearly as large as Connecticut.
NASA images have captured the decline of aquifers in the 220-mile long San Joaquin Valley that is the nation’s most productive farm region with the eight counties producing 12.8 percent of the overall value of the nation’s crops as well as the majority of fruits and vegetables.
The possibility that almond production and processing jobs that account for 104,000 jobs including 97,000 throughout the Central Valley could play a key role in reversing dropping aquifers was shared with Manteca Rotary Almond Board of California Manager of Industrial Relations Jenny Nicolau during last week’s meeting at Ernie’s Rendezvous Room.
“They (scientists) are looking at flooding orchards when almonds are dormant to recharge water tables,” Nicolau said.
Given there are 1.02 million acres of almonds planted in California — including 890,000 acres with trees bearing nuts — it has the potential to become the biggest large-scale groundwater recharge undertaking in California. Water table declines have accelerated with the drought forcing more farmers to turn to pumping as surface water supplies started drying up.
While such an undertaking may help stop future depletion, more problematic is gradual, irreversible compaction of the earth that occurs due to over drafting.
San Joaquin County — as the northern most county in the San Joaquin Valley — has the smallest issue with overdrafting although urbanization threatens to change that. The problem starts accelerating as you head south into Stanislaus County.
It is worst near Dos Palos and other areas in the central part of the valley. A photo taken in 1999 by the Unified States Geological Survey shows a man standing next to a utility pole near Mendota. At ground level is a sign reading where the elevation of the land was in 1977. Some 28 feet above is a sign marking where the elevation of the ground was at in 1925.
Damage between 1955 to 1970 linked to subsidence was placed at $1.3 billion in current dollars. The report by the California Water Foundation notes that figure includes bridges slumping, levees dropping and well casings collapsing.
California almond facts noted by Nicolau includes:
The Central Valley grows 82 percent of the world’s almond crop with Eastern Europe a distance second at 8 percent.
California is the only place in the United States where almonds are grown due to the critical Mediterranean climate featuring mild winters and abundant sunshine. The only other four areas in the world that can accommodate almonds are the coast of Chile, the Mediterranean, the extreme southwest coast of Africa and the southwest coast of Australia.
35 percent of all almonds grown in California are consumed in the United States.
In the past five years U.S. consumption has risen by 33 percent.
Almonds are the state’s top export crop in terms of dollar value. It is the No.2 farm commodity behind dairy.
California shipped 1.81 billion pounds of almonds worldwide with Spain being the top destination among 90 countries they are shipped.
The annual impact of almond production on the California economy is $21.5 billion. Almonds add $11 billion to the state’s gross product.
San Joaquin County grows 5.04 percent of the state’s almonds with almost all in the Manteca, Ripon, Escalon area representing an annual production of $578 million making it the top farm product in the county that produced an overall farm harvest in 2014 valued at $3.23 billion.
Stanislaus County grows 14 percent of the state’s almonds making it the third largest county for nut production.
More irrigated farmland in California is planted in almonds — 13 percent — than any other crop although it only uses 9 percent of developed water sources. California’s total managed water is shared between urban uses at 10 percent, agricultural at 40 percent, and the environment at 50 percent.
No other crop is as miserly with water in terms of irrigation as 70 percent of all almonds orchards employ micro drip irrigation systems.
91 percent of the state’s almonds are grown on family farms.
74 percent of all almond orchards consist of 100 acres or less.