Desalination

After decades of work, Israel now gets about a quarter of its water from the sea. But experts say desalination is not a magic bullet, and conservation and infrastructure fixes are also needed.

During its last major drought, Santa Barbara built a desalination plant. It was never used. Now it's being reopened, but critics say desalination is costly, energy-intensive and may harm marine life.

The Lawrence Berkeley National Laboratory has pinpointed the tools with the greatest impact, from affordable tablets for schoolkids to an electrical grid in a box.