On the bottom of what used to be a shallow bay, bulldozers and excavators are clawing into the dry lakebed.

Over the past decade, the shore of the Salton Sea has receded more than a mile at Red Hill Bay, leaving a dusty plain of salt-laden soil that crunches and crumbles underfoot.

Workers have been using machines to dig down to a clay layer, starting to build berms so the area can be flooded and transformed into more than 500 acres of wetlands.