From Taos News (J.R. Logan):
Shortly after midnight last Friday (April 1), irrigators in Colorado’s San Luis Valley opened the gate on a diversion dam and pushed 80,000 gallons-a-minute of the Río Grande into a canal system that includes 210 miles of ditch and serves hundreds of farmers.
April 1 marks the beginning of irrigation season for the valley’s farmers. The Río Grande is at the heart of the valley’s massive agricultural industry, and farmers waste no time in taking their share…
Agriculture is big business north of the border. An incredibly complex infrastructure of dams and canals spreads water from the river across the valley, most of it to fill shallow aquifers that feed hundreds of center pivot sprinklers. But the water demands of the industry on that side of the state line in spring often leave little water in the river by the time it hits New Mexico. At times in recent years, the river at the border was more than 90 percent smaller than when it entered the valley.
Environmentalists complain that dramatically altering the natural pulse of spring runoff has devastating ecological effects that extend far downstream. And rafting outfitters in Taos County have said Colorado irrigators sucking most of the river dry hurts their business by making popular sections of the river — namely the Taos Box through the Río Grande del Norte National Monument — impassible. “They’re starting earlier, and it’s more intense,” says Cisco Guevara, outfitter and owner of Los River Runners. Guevara and other outfits started running the Taos Box in March, when early runoff swelled the river enough to get a boat through. But between April 1 and April 5, flows at the state line dropped by more than half…
Exactly how low the flow will go depends on the snowpack in the Río Grande’s headwaters in Colorado. Under the Río Grande Compact — a water sharing agreement struck by Colorado, New Mexico and Texas nearly 80 years ago — Colorado must “deliver” a certain percentage of the river to the state line every year. That percentage varies, depending on the total amount of water that goes downriver each year.
The catch – for New Mexico – is that the delivery is calculated on an annual basis, meaning Colorado can let every drop of the river go to New Mexico during the fall and winter while taking most of the river during the spring and summer and still fulfill its debt to New Mexico.
Unfortunately for river rats like Guevara, peak rafting season happens to coincide with irrigation season.
Still, the demands of thirsty irrigators in Colorado don’t necessarily mean the river will shrink to a trickle at the state line. Peak runoff is still weeks off, and when ample snowpack melts in earnest and the Río Grande really gets rolling, farmers can only take so much water, meaning there’s plenty left for those downstream…
As of Wednesday (April 6), snowpack in the Río Grande headwaters was at 86 percent of the 30-year average, suggesting flows this year will be slightly below average. But that could change if the mountains see additional spring snow storms that bolster snowpack, as was the case last year.
Raft guides aren’t the only ones griping about the way water in the Río Grande is shared.
In 2014, Santa Fe-based environmental group WildEarth Guardians served notice of its intent to sue the state of Colorado, arguing extreme diversions for agricultural use imperiled the habitat of the endangered silvery minnow in the Middle Río Grande Valley.
No such lawsuit has been filed. Instead, the group is suing the state of New Mexico, hoping to compel the state engineer to limit the amount of water that can be diverted by the Middle Río Grande Conservancy District, which serves farmers in the center of the state.