For as long as the Salton Sea has faced the threat of ecological collapse, some local residents and environmentalists have advocated a radical cure for the deteriorating lake: a large infusion of ocean water.

By moving desalinated seawater across the desert, they say, California could stop its largest lake from shrinking and growing saltier and could restore its once-thriving ecosystem. Without more water, they argue, the lake will continue to decline, and its retreating shorelines will expose growing stretches of dry lake bed that spew hazardous dust and greenhouse gases.