Without sufficient time for study and planning, critics charge, the money spent could bring little benefit to the area's wildlife. This aerial view of the Salton Sea shows agricultural fields to the south, urban development on the north, and the Mexico-California border marked in brown. The Salton Sea, shown in the photo at right, with the California-Mexico border marked in brown, was created by accident when an irrigation canal burst in 1905. It is now California's largest inland body of water. Accumulating salts include selenium and other toxic minerals naturally present in the valley's sedimentary soils.
Native fish are now absent, although imported African tilapia now support a thriving sport fishery.
The chief focus of environmentalists' concerns is a series of catastrophic die-offs among migratory birds. The Salton Sea is one of very few remaining water bodies in southern California. The region once had extensive natural wetlands, but most have been drained for agriculture. As a result the Salton Sea, despite its concentrated pollution levels, hosts millions of migratory water birds in the winter. The Salton Sea has been declared a National Wildlife Refuge because of its importance to birds.