Photos by Eric Mullens The current low levels of the Rio Grande, similar to those shown here, are purposely designed to divert recharge water into the San Luis Valley aquifers. Recharge diversions will end in about a week, and the river will show higher levels after that time.

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By RUTH HEIDE

ALAMOSA — If the Rio Grande appears low right now, it’s supposed to.

Less water in the river now could mean more water on the crops next year.

Colorado Division of Water Resources Division III Division Engineer Craig Cotten explained that the currently low water levels in the river are the result of recharge diversions this fall.

Recharging water into the aquifers will give the Valley a head start next year, just as the recharge last winter assisted the water division in managing the system and assisted irrigators in managing their crops this year.

“It really did help us out this year,” Cotten said. “That’s the reason we did not have curtailment of water for compact deliveries much of the season.”

In addition, more than 5,000 acre feet of compact water was stored in Rio Grande Reservoir this year that will be released next year for compact purposes.

“I think overall it was a good year,” Cotten said. He added that was even with a below-average river on the Rio Grande.

“We are still diverting some water in some ditches,” Cotten said on Tuesday.

He clarified that the water being diverted now is solely in ditches that are able to take water for recharge. Those diversions will end in about a week, at the end of November. The Rio Grande will then begin to show higher levels.

The later diversions were only on the Rio Grande. Ditches on the Conejos River system were shut off around November 1.

One of the reasons for the recharge diversions this fall was expressly to reduce the amount of water that will be over delivered downstream as part of the interstate Rio Grande Compact, Cotten explained.

“We were a little ahead of schedule for deliveries for the compact at the end of the traditional irrigation season the end of October,” Cotten said, “so we extended the irrigation season a little bit on the Rio Grande, for about an additional week to allow the irrigation ditches to continue running into November. Since then we have allowed the recharge ditches to take some water. That’s why the river is fairly low right now.”

If the water division had not allowed more water to be diverted in the Valley, Colorado would have ended the year with a higher over-delivery downriver. Water delivered over the amount obligated through the Rio Grande Compact would be stored in the Elephant Butte Reservoir in New Mexico where it would remain as “credit” water for Colorado.

“We do lose some for evaporation,” Cotten explained. That would be like putting money in savings but having less in the account when the depositor was ready to draw the money back out.

“We think it is better to keep the water up here and recharge the aquifers,” Cotten said.

Last year Colorado over delivered about 10,000 acre feet of water to downstream states and had expected to over deliver several thousand acre feet this year. Keeping more of the water in the Valley through recharge diversions, however, cut the amount of over delivery to about 2,000 acre feet. The final numbers will be verified when representatives from the states involved in the Rio Grande Compact meet in February.

With an annual forecasted index of 950,000 acre feet this year, to come within 2,000 acre feet is pretty close reckoning, Cotten explained.

“I think we are doing all right,” he said.

He added that it is better to error slightly on the over-delivery end than under-delivery.

As far as the warm, dry November to this point, Cotten said the basin snowpack is below average for this time of year, but that could change literally overnight with a snowstorm.

“It changes a lot this time of year,” he said. It is still too early in the season to predict how the snowpack will ultimately turn out, he said.