During drought, massive rock wall spanning Delta channel wards off the salty sea
The creeks are desert-dry, the reservoirs are frighteningly low, and now 150,000 tons of rock have been dumped into the Delta. During a typical summer, carefully coordinated releases from upstream dams help keep saltwater from intruding too far into the interior Delta, where it could threaten the state’s water supply. But this is not a typical year, and by early May state water managers realized they wouldn’t have enough storage to maintain the standard hydraulic salinity barrier. So they resorted to rocks instead.