The Colorado River supplies water to seven states, including New Mexico, before crossing the border into Mexico. Then—theoretically, nowadays—it reaches the Sea of Cortez. Demands from cities and farms, along with climate change, strain the river and affect its flows. Now, a new study shows that even though annual precipitation increased slightly between 1916 and 2014, Colorado River flows declined by 16.5 percent during that same time period. That’s thanks, in large part, to “unprecedented basin-wide warming.” Warming reduces snowpack and increases the amount of water plants demand.
It’s likely you’ve already seen the big headlines of the week: fires, floods and the resignation of Scott Pruitt from the head of the U.S. Environmental Protection Agency. Here are some of the less flashy stories you may have missed recently:
-Writing for Water Deeply, Brent Gardner-Smith reports that the Upper Colorado River Commission is shuttering a pilot program that paid irrigators to fallow fields. The four-year program paid people in New Mexico, Utah, Colorado and Wyoming about $200 an acre foot to hold off watering their fields so more water could be stored in Lake Powell. This year, the program will pay out almost $4 million to participating farmers and ranchers. According to the story:
The ending of the program does not mean the commission is giving up on getting more water into the upper Colorado River system in order to raise water levels in Lake Powell, as that interest continues to grow as the drought that began in 2000 lingers.
In early June, more than 1,000 people near Durango, Colorado, had to leave their homes as the 416 Fire swept across the landscape. Following a dismal snowpack, the region experienced a spring so hot and dry that the U.S. Drought Monitor labeled conditions “exceptional drought,” the worst category. Colorado wasn’t alone. An irregular bull’s-eye of dryness radiated outward from the entire Four Corners region, where Colorado meets New Mexico, Arizona and Utah. These circumstances offer something of a preview of the coming decades: While experts say the Southwest will continue to experience swings in precipitation from year to year, overall climate change is making the region and its river basins hotter and drier.
The signs of rising temperatures are obvious across New Mexico right now, from the mountains to the river valleys, and from rangelands to suburban backyards. “Climate change for the Southwest is all about water,” said Jonathan Overpeck, who has spent decades studying climate change and its impacts in the southwestern United States. Warming affects the amount of water flowing in streams, and the amount of water available to nourish forests, agricultural fields and orchards. There’s also the physics of the matter: A warmer atmosphere holds more moisture, demanding more from land surfaces. Plants need more water, too.
This weekend’s warm and windy conditions were good for hiking or kite-flying. But they were tough on a river everyone is already expecting to be low on runoff this spring and summer. According to the National Water and Climate Center’s forecast for the Rio Grande Basin, the water supply outlook for spring and summer remains “dire.” In his monthly email, forecast hydrologist Angus Goodbody noted that while storms did hit the mountains in February, particularly along the headwaters in Colorado, snowpack in some parts of the Sangre de Cristo’s continued to decline. That means the river and its tributaries will receive less runoff than normal this spring and summer—and many areas may reach or break historic low flows. Last week, a new study in the peer-reviewed journal, Nature, also heralded troubling news.
LA CIÉNEGA DE SANTA CLARA, MÉXICO— Alejandra Calvo crosses a barren stretch of desert in Sonora, México almost daily during certain times of the year. The route could easily disappear beneath blowing dust and when rain does fall here, it renders the road impassable. There are no birds or wildlife here, not even any visible plants. It wasn’t always like this: Until the 1960s, the Colorado River spread across this delta on its path to the Sea of Cortez. Originally from Chiapas, Calvo is a biologist who works for ProNatura Noroeste, a conservation group based in northwestern Mexico.
Over the next week, New Mexico Political Report will be reporting from…not New Mexico. Instead, we’ll be taking a closer look at the Colorado River. The Colorado delivers water to more than 36 million people in seven states and two countries. Its waters carved the Grand Canyon and, far more recently, allowed the growth of Sunbelt cities like Phoenix and Tucson. (No, neither is near the Colorado.
This week, the U.S. Environmental Protection Agency announced that along with the U.S. Army Corps of Engineers, finalized the “Waters of the United States” applicability date. Last March, President Donald Trump directed the agencies to review the “Clean Water Rule” also known as the Waters of the U.S. Rule, which was finalized in 2015 as a way to clarify confusion over parts of the Clean Water Act. The rule applies to navigable waterways and their tributaries. Under the rule, a tributary doesn’t need to be a continuously flowing body of water. But it must have flowing water—marked by a bed, bank and high water mark—to warrant protection.