San Luis Valley unconfined aquifer storage up 119,000 acre-feet

San Luis Valley Groundwater
San Luis Valley Groundwater

From The Pueblo Chieftain (Matt Hildner):

For the second year in a row, water o–cials have seen a recovery in one of the aquifers that farmers lean on heavily in the San Luis Valley.

The unconfined aquifer, which is the shallower of the valley’s two major groundwater bodies, saw its volume increase by 119,000 acre-feet.

That bump follows an increase of 71,000 acre-feet from the year before.

“If these last couple of years could just continue, it would be wonderful,” said Allen Davey, an engineer for the Rio Grande Water Conservation District. “We’ve seen significant recovery.”

The district maintains a network of monitoring wells in the north-central part of the valley and has kept track of the shallow aquifer’s levels since 1976.

The last two years have marked a reversal from a 13-year run that saw the shallow aquifer drop by more than a million acre-feet due to drought and over-pumping…

Davey credited the improvements of the last two years to e€orts by Subdistrict No. 1 to reduce pumping.

The subdistrict, which lies in the north-central part of the valley, levies a fee on its members for pumping to raise money for land fallowing and also to pay for damages pumping causes to surface water supplies.

Davey cited pumping records from 2000 that showed well pumping withdrew 391,000 acrefeet from the shallow aquifer. He expects that figure to come in at around 230,000 acre-feet this year.

Some subdistrict members also enrolled in the federal Conservation Reserve Enhancement Program, which pays farmers to fallow their land.

So far, 5,854 acres of land had been fallowed under the program. There were 109 wells associated with that acreage that pumped roughly 10,000 acre-feet annually.

The volume of the shallow aquifer would have to improve by roughly another 700,000 acre-feet to meet the management objectives laid out by the subdistrict.