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.