LONG BEACH, Calif. -- There's no disputing that the water in the Los Angeles River is dirty and exceeds Clean Water Act limits. The big question is who's responsible for pollution in that concrete-lined channel. An appeals court held that it is the problem of the permit holder, the Los Angeles County Flood Control District, but the district blames stormwater discharges in stretches of the river that are beyond its reach. The Supreme Court will try to sort it out.