Rio Grande Basin: Water year recap

From the Valley Courier (Ruth Heide):

[Chris Landry executive director of the Center for Snow & Avalanche Studies] and his team compared snow core samples to determine the number of dust events during a winter season. He reported an increase in dust events from 2008 to 2009 from 7 to 12 at the site studied in the Rio Grande Basin. The concentration of dust was heavier as well. In 2008 the concentration was 12 grams per meter while in 2009 it was 55 grams per meter. He said that is an enormous amount of material. “The San Juans in particular experienced the most dramatic advance in the state in snowmelt timing,” Landry said.

He said the reason for more dust might have simply been because this past winter was windier. He said not much data is available about the source of the dirt, presumably blowing in from the western desert. Landry said the dust layers on snow were fairly consistent statewide from Rabbit Ears Pass in the north to Wolf Creek Pass in the San Luis Valley.

The report from Division of Water Resources Division Engineer for Division III Craig Cotten bore out the fact that the snow melted off early this year. He told the water board the reasons for the early run off were probably dust on the snow and warmer temperatures in May. He showed graphs illustrating a dramatic decline in river flows in May. However, Cotten said irrigators were curtailed less than usual this year because of winter recharge and deliveries to downstream states. “We only had a month of curtailment on the Rio Grande this year,” he said.

On the Conejos system, curtailments were also zero during most of the run off period, from April 15 to July 9, Cotten said. The Conejos system went back to zero curtailment the end of August. He added, “We also had the entire suite of ditches in priority and diverting. The most junior priority on the Conejos system diverted for almost three months this year.”

Both river systems will likely over deliver the amount of water required by the Rio Grande Compact interstate agreement with downstream states. At this point Cotten is estimating an over delivery of 9,700 acre feet on the Rio Grande, about the same amount of water carried over in credit last year. He told the water board the ditches would be turned off October 31 under standard operating procedure but if the weather is warm the first part of November, water may run longer in order to recharge the Valley and reduce the amount of over delivered water downstream.

More Rio Grande Basin coverage here.

Platoro Reservoir: Dam safety upgrades

From The Pueblo Chieftain (Chris Woodka):

U.S. Rep. John Salazar, D-Colo., secured a request for $646,000 in the energy and water appropriations bill. Salazar sits on the Appropriations Energy and Water Subcommittee, which approved the funding. The bill must still gain House and Senate approval. Platoro Reservoir is used for flood control and for re-regulating the flows of the Conejos River for irrigation in the San Luis Valley Project of the Bureau of Reclamation. Flows are crucial to the Rio Grande Compact with Texas and New Mexico The reservoir is used by the Conejos Water Conservancy District as well as a large number of hunters, fishermen and recreational enthusiasts. Funds will go toward further inspection of deteriorating inflow pipes, and to install a system to carry increased bypass flows. “Platoro Reservoir, built in 1951, can no longer handle our wintertime by-pass flows creating a critical dam safety issue,” Salazar said. “This funding will help preserve the life and use of the reservoir for agriculture, flood-control and recreational use.”