What to do when runoff falls short?

Spring runoff represents a combination of natural snowmelt and decisions by a host of water management agencies to increase flow by releasing water stored behind upstream dams or to reduce it by diverting water at dams for use by farms and cities.

The endangered Rio Grande silvery minnow’s dwindling population has triggered a new bureaucratic battle this year over how much water the fish needs.

According to an analysis by the New Mexico Interstate Stream Commission, the river has only once since the 1990s, in 2005, had enough water to meet the Fish and Wildlife Service’s “conservation objective” for spring runoff high enough to help the endangered minnow’s population recover.

The gap between flow goals and the reality of dry-year flows on the river has led to high-level negotiations among the federal agencies trying to manage the Rio Grande, including the Fish and Wildlife Service, the Bureau of Reclamation and the Army Corps of Engineers.

“There are a lot of conflicting needs,” Janet Bair, ecological program services supervisor in the Fish and Wildlife Service’s Albuquerque office, said in an interview Monday. “Water is needed by the minnow. Water is needed by the irrigators. Water is needed by the cities.”

The agencies are struggling to find a middle ground, with steps that could be taken to help the fish during years when there is not enough water to meet the flow goals, according to a copy of a Fish and Wildlife Service briefing document obtained by the Journal.

The Fish and Wildlife Service in recent months had repeatedly refused to provide documents related to the discussions or permit interviews with its staff. Most recently, agency spokesman Tom Buckley in an email message called the documents from a late February briefing for river managers “still preliminary/draft and not ready for prime time.” After state officials provided the Journal with a copy of a related briefing document, the Fish and Wildlife Service agreed to make staff available to answer questions about its contents.

Bair said the high spring flow numbers, which have caused consternation among some water managers who wondered where the water would come from, were never meant to be binding.

“They’re not intended to be an edict,” she said. “They’re intended to be a target to shoot for each year.”

The goal, said Hamman of the Bureau of Reclamation, is to find a way to meet the fish’s needs without having to curtail human water use. A completed plan is expected this summer.

The minnow, once plentiful from the Chama River to the Gulf of Mexico, is now only found in central New Mexico and a stretch of Rio Grande in Texas where an experimental population was recently reintroduced. In its New Mexico refuge, the fish has fared poorly during the recent drought.

At issue in the minnow water discussion are central questions about the future of water management on the Rio Grande, with tension between various water users and legal requirements under the Endangered Species Act to try to prop up dwindling populations of the tiny fish.

Among the options for helping the fish during low flow years is the creation of engineered habitat, areas of riverside bosque dug out to create backwaters for minnow spawning, said Rolf Schmidt-Petersen of the Interstate Stream Commission. The agency and others are currently working on one such project on the Rio Grande’s western bank in central Albuquerque.

Another possible solution to help the fish that does not require high flows is construction of fish passages around the river’s irrigation diversion dams, Bair said.
— This article appeared on page A1 of the Albuquerque Journal