From the Albuquerque Journal (John Fleck):
Colorado’s use of Rio Grande water is depriving the river of spring flows needed to keep the endangered Rio Grande silvery minnow alive, an environmental group charged in a legal notice filed this week.
The notice by the Santa Fe-based group WildEarth Guardians opens a new legal front in the struggle over environmental flows in the Rio Grande, a struggle that until now had focused on tradeoffs among water interests within New Mexico.
The filing, a formal notice of intent to sue the Colorado Department of Natural Resources over its water management on the Rio Grande, charges that irrigation in the San Luis Valley, north of the New Mexico-Colorado border, is significantly reducing the spring runoff peak, which the minnow depends on for spawning.
More endangered/threatened species coverage here.