UC Santa Barbara researchers were closing tracking the content of the mud and other materials brought to the ocean for dumping after the 2018 Montecito Debris Flow.
Thousands of truckloads of debris were dumped as a way to clear out debris basins and streets.
Testing at Goleta Beach showed evidence of human waste, though the bacteria the scientists had recorded dissipated with the new ocean currents.
The scientists believe that the waste was coming from broken sewer and septic systems.
They're recommending that in the future, officials should test the materials they're dumping before its brought to the beach.