Photo by Eric Mullens The Rio Grande River near the Colorado State Veterans Center at Homelake in Rio Grande County shows a good flow of water one week prior to the official start of summer 2009, but disappointing snow pack doesn’t assure this will be the scene in the next months to come.

Snow’s down, rain’s up



By RUTH HEIDE

ALAMOSA — Although the snow has largely melted from the mountains, the San Luis Valley’s summer rains have created a rare occurrence - zero curtailment on irrigators along the Rio Grande and Conejos River systems.

Division of Water Resources Division Engineer for Division 3 Craig Cotten explained on Thursday that the division is currently not cutting irrigators short because sufficient water is flowing downstream to meet the Rio Grande Compact obligations to New Mexico and Texas.

He said the June forecast from the Natural Resources Conservation Service (NRCS) actually rose 5,000 acre feet from May. NRCS is now predicting 590,000 acre feet on the Rio Grande this year. That is slightly below average which is about 650,000 acre feet.

Of that amount, the Valley will be obligated to send downstream 158,400 acre feet of water, or 27 percent.

“That’s what we have to deliver to the state line from the Rio Grande portion,” Cotten explained during a well rules advisory meeting in Alamosa on Thursday.

The Rio Grande does not have to send 27 percent downstream right now, however, because the Rio Grande delivered 100 percent through the winter, sent more water downstream during the runoff period and is experiencing good return flows all the way through the system. Cotten said the Rio Grande would only need to send 8 percent downstream currently to meet its Rio Grande Compact obligation.

“Our current curtailment on the Rio Grande is effectively zero. We do have a curtailment on our daily sheet but we add back some water, make some adjustments, so it is effectively zero on the curtailment.”

The same is true on the Conejos River system, Cotten said. The NRCS forecast for the Conejos system is 345,000 acre feet, up 15,000 acre feet from last month. The obligation to downstream states from that total is 143,200 acre feet or 42 percent.

The current delivery target is 16 percent but because of the amount of water in the system the water division is not curtailing irrigators on the Conejos system “which is kind of an unusual situation that we don’t have curtailment actually occurring on either one of the rivers right now,” Cotten said.

“We have a delivery target we are meeting but we don’t have to impose a curtailment to meet that.”

The snowpack update was not as encouraging. Cotten said on April 20 the Rio Grande Basin had above average snowpack. It then dropped hard, and the snowpack is virtually gone according to Cotten.

The snowpack melted quickly due to above average temperatures and significant dust on the snow. “That really causes the snow to heat up fast and melt out fast,” Cotten said.

The Conejos system peaked the first part of May, and the Rio Grande peaked around May 8, about three weeks earlier than normal.

“We are significantly lower right now at this time of year than we usually are,” Cotten said.

Saguache Creek peaked the end of May which is about normal, Cotten added. He said that might indicate the northern part of the Valley had less dust on the snow.

Kerber Creek near Villa Grove peaked almost exactly on target the end of May, Cotten said.

“We are dropping off that peak pretty hard,” he added.

The precipitation forecast for July through September for this region calls for above average precipitation, Cotten said. “It’s been like that so far,” he said.