Yellow in the Ocean? T Street Beach San Clemente, California- Orange County

Yesterday was a gorgeous beach day in San Clemente, CA. At T-Street Beach the water was warm and shallow enough to walk out swim and boogie board. Only a couple cautions, warm water also brought a string ray that may have stung someone earlier in the day where we were now splashing, later there was some concern of rip currents. But the spotted yellow flag was not the only yellow spotted at the beach. The biggest concern in my opinion was the bright yellow we could see first from the cliff above T-Street. The yellow colored water streaked moving south from the San Clemente Pier and south of T-Street. People swam and splashed anyway. After a few hours the yellow was finally pushed south and spread and you could no longer see notice it. There are piles and piles of a long seaweed bed that is stretched across the coastline making the ocean blue somewhat brown. Is this related to the yellow, was this yellow dumped into our water? This yellow as bright as paint, what was it? Glad there are showers at the beach.

Comments welcomed.