Why the Supreme Court granted certiorari in Los Angeles County Flood Control District v. Natural Resources Defense Council, Inc., 673 F.3d 880 (9th Cir. 2011), is a mystery. The Court declined certiorari on one Clean Water Act (CWA) question presented in the petition, but then granted it on a second, which is unlikely to be resolved without actually reaching at least some of the touchy issues that may have led it to decline certiorari on the first question. Regardless, the case is particularly important for municipal governments that are attempting to address flooding and stormwater management challenges in a regional context. The Court heard oral argument on December 4.