National Wildlife Federation: “For thirty years the federal Clean Water Act broadly protected waters in the nation and across the Southwest. It sought, with a great deal of success, to safeguard important waters from pollution and destruction. Historically, it applied to waters from the Rio Grande to playa lakes. However, now the protections of the Act are being whittled away. Two recent U.S. Supreme Court decisions, Solid Waste Agency of Northern Cook County v. U.S. Army Corps of Engineers (2001) and Rapanos v. United States (2006), have placed protections of many of the nation’s waters, such as intermittent and ephemeral streams and so-called “isolated” wetlands, in doubt. While these Supreme Court decisions have not overturned any of the current regulations that broadly protect waters, they have created significant legal
confusion over the scope of the Act’s protections….the Southwest has a disproportionate number of waters that are at-risk of losing federal protection because of agency guidance. In all Southwest states, the percentage of streams that are at risk because they do not flow year round is much higher than the national average, which is already an alarming 59 percent of all stream miles. For instance, in Arizona approximately 96 percent of streams are at risk of losing federal protections. Similarly, many of the region’s most important wetlands are either geographically “isolated” or associated with streams that may no longer be protected. In conjunction with state laws that often provide little or no protection for these at-risk resources, a prolonged drought affecting much of the region, and climate change impacts add unprecedented stress to waters in the area, making the threat to waters in the Southwest more severe than it has been in a generation.”