WATER TRANSFERS TO SAN DIEGO ARE DRYING UP CALIFORNIA'S LARGEST LAKE

The sale of water from California's Imperial Valley to San Diego deprives the Salton Sea of farm runoff, its main source of inflows. After 2017, San Diego and other local water agencies are no longer required to deliver water to the Salton Sea to help offset the losses.

The state of California has agreed to spearhead efforts to restore the lake and offset environmental damages from the water sale. In 2007, it proposed a $9 billion plan to create a horseshoe-shaped lake in the northern basin and saline habitat in other parts of the lake. Less ambitious plans have also been floated, but little has been done.

EXPOSED LAKEBEDS STIR DUST, EXACERBATING RESPIRATORY ILLS

The lake's shrinkage has exposed about 18 square miles of salt-encrusted lakebed since 2005. Pacific Institute, which has done extensive research on the lake, estimates that about 100 additional square miles will be exposed by 2030 without preventive measures and another 50 square miles by 2045.

Imperial County's air quality already fails federal and state standards, and public health experts warn that increased dust from the Salton Sea lakebed will make it worse.

FISH KILLS ARE COMMON

Winds periodically stir hydrogen sulfide from the bottom of the lake, stripping oxygen from water closer to the surface, producing a rotten-egg stench and killing fish.

More than 60 species of fish have been brought to the Salton Sea over the years, said Chris Schoneman, project leader of the Sonny Bono Salton Sea National Refuge. The hearty tilapia is the only one left in abundance, and increasingly salinity endangers it.

MORE THAN 400 BIRD SPECIES ARE SPOTTED

The Sonny Bono Salton Sea National Wildlife Refuge has recorded 424 species of birds. Located on the Pacific flyway, heavy migrations of waterfowl, marsh and seabirds occur during spring and fall. For them, the lake is a desert oasis from vast stretches of rock and sand.

IT HAS ONE OF NORTH AMERICA'S LARGEST GEOTHERMAL DEPOSITS

Magma from the earth's center rises through shifting tectonic plates, drawing about a dozen geothermal plants to the lake's southern shores.

A shrinking lake is actually good for geothermal development. Energy Source LLC opened the first new geothermal plant in 20 years in 2012, a $400 million investment. Vince Signorotti, vice president for resources and real estate assets, says exposed lakebed is potentially new territory for exploration.