Using strobe lights to guide juvenile salmon

The Bureau is testing an underwater light, sound, and bubble fish guidance system to determine if it’s effective at keeping downstream migrating Chinook in the San Joaquin River. In previous years a physical barrier has been installed at the confluence of the San Joaquin and Old River to keep fish in the San Joaquin River, where tests suggest their downstream survival rates are higher. The physical barrier is no longer installed because it may impact Delta Smelt movement.