NM monitoring well helps water planners

SANTA FE (AP) - A half-mile deep monitoring well is aimed at giving new information to Santa Fe’s water planners.

City water resources coordinator Claudia Borchert says New Mexico’s capital city has never had a good handle on how different layers in the aquifer are interconnected.

Contractors started drilling the 2,660-foot deep monitoring well at the end of March.

The project used concrete seals to isolate seven different zones, and water samples can be collected at different depths.

"By taking the discrete water chemistries and these pumping tests we'll learn more about how connected they are," Borchert told the Santa Fe New Mexican. "That becomes important when we want to put in a new well. We have to understand the connectedness to understand the ramifications of putting in a deeper well."

Santa Fe has the right to pump 4,865 acre-feet of water a year, but doesn't have the capacity to pump that much. An acre-foot equals 325,851 gallons of water, or enough to meet the annual needsof one to two U.S. households.

"There's no information about water in the city deeper than 1,200 feet," project hydrogeologist Jim Street said.

The project is collecting rock cuttings, water samples and water-flow data from the well, each offering scientists different information about what's happening with the aquifer.

Rock cuttings from the bore hole as the well was drilled help project officials read the geology of the underlying ground and where the best water-producing zones occur.

Borchert said Santa Fe is trying to create a water system responsive to conditions such as drought. The city in the future will have three primary water sources - two reservoirs east of the city, water drawn from the Rio Grande through a diversion project under construction and city wells.

The monitoring well is next to a production well Borchert said is the city's best.

"If we want to explore where we should put another well that might be a better producer, this is a good place to start," she said.

Street said deeper wells in New Mexico typically have worse water quality, such has high arsenic levels. However, the monitoring well is proving to have fairly good quality water even at deeper depths.

The total monitoring project will cost an estimated $1 million.