Mexican and U.S. enviros are teaming up to pressure the U.S. government into allocating more water from the Colorado River to protect endangered species, a move that could spur new legal battles over water in the Western U.S. Fourteen enviro groups, including four from Mexico, have announced their intent to file suit within 60 days against the U.S. government for allegedly violating the Endangered Species Act by not providing enough water for fish and other wildlife downstream in Arizona and Mexico. Enviros estimate that some 75 percent of fish species in the Colorado River’s Mexican delta have either gone extinct or are in danger of doing so, largely because most river water is diverted to farms and cities in the southwestern U.S.