Prolonged spring winds, continued drought wreaks havoc on SLV river basins
SAN LUIS VALLEY
WATER flow at the Rio Grande gauging station near Del Norte peaked on May 8, as did water flow on the Alamosa River above Terrace Reservoir. Saguache Creek peaked May 9, and the Farmers Union Canal, a key delivery of senior water rights, could be out of water by June 1.
“We’re wounded and we’re leaking blood,” said Pat McDermott, staff engineer for the Colorado Division of Water Resources Division 3 office in the San Luis Valley.
The long-season of spring winds has brought even more dryness to the Valley’s river basins. The snow in the high country is brown and gray due to the winds, which attracts the sun and makes water flow peaks come earlier, McDermott said.
Medano Creek is already slowing and may not even have enough strength to show up in the parking lot at the Great Sand Dunes National Park for the typical Memorial Weekend rush of beachgoers.
“Earlier runoff, earlier peak runoff and then swift decline in our rivers is dangerous not only for irrigators but dangerous to the environment,” McDermott said in talking to Alamosa Citizen. “The river heats up, fish die … This is very, very concerning to us.”
Peak water flows in 2022 came two to three weeks earlier than normal, McDermott said. But that’s only part of the problem on the Upper Rio Grande Basin and with the San Luis Valley aquifers, confined and unconfined.
As concerning is the rapid decline in stream flow to bottom levels normally found later in the summer, preferably August into September. Water storage in most of the reservoirs is at 25 percent of capacity. The Valley is facing another dry summer, with forecasts showing below normal precipitation and conditions that make for high wildfire danger in the forests and the backcountry.
Pray for summer rain
It’s about all anyone can do. Otherwise, for Valley farmers, “only those with very senior surface water rights and/or sufficient irrigation wells will have adequate water supply to finish their crops,” McDermott said.
The high desert San Luis Valley normally would get 7 to 7.5 inches of rain annually, but lately – and maybe the new normal – only 4 to 4.5 inches of rain has fallen on the Valley floor. For longtime watchers of the Upper Rio Grande Basin, it’s starting to reflect the droughts of the 1950s.
“When you string together a bunch of below normal years, losing two inches of precipitation is really hard on our environment,” said McDermott.
Erratic levels of precipitation and more extreme weather events is the new standard on the Rio Grande. The only question is how much worse can it get, and that answer largely depends on Mother Nature.