The U.S. and Mexican governments are close to signing a landmark Colorado River deal that will establish rules for sharing water over the next decade and lay out cooperative efforts intended to head off severe shortages. Mexican and American officials have scheduled a signing ceremony on Sept. 26 in Ciudad Juárez, officials at California water districts said this week. They said that formal event will be followed by a ceremonial signing in Santa Fe, New Mexico, on Sept. 27 attended by representatives from U.S. states.