Southern California voters toppled one Imperial Irrigation District board member and re-elected another, in a low-turnout election that nonetheless could have major consequences for millions of people who depend on water from the Colorado River. With all precincts reporting, El Centro city councilmember Alex Cardenas led 55-45 percent over incumbent IID director Juanita Salas, with about 1,800 votes counted. Meanwhile, IID board president Jim Hanks led challenger Raul Navarro, a member of Calipatria Unified School District’s board of trustees, 52-48, with fewer than 2,200 votes counted.