The Hawaii Department of Health says it has identified the cause of the brown water advisory for Kauai waters.
Health officials say the bloom organism appears to be a species of the cyanobacterial genus Trichodesmium, possibly the species T. erythraeum. Trichodesmium is found in tropical and subtropical waters that have low nutrient levels.
As a precaution, the public is advised to stay out of waters from Moloaa Bay to Anahola Bay due to the possibility of swimmer's itch.
Fire crews on the Big Island were called on Monday at around 12:20 p.m. for a report of patches of a foamy white substance on the shoreline and in the water fronting Coconut Island in Hilo Bay.
Hazmat tests on the substance came back negative. The Hawaii Department of Land and Natural Resources say the white substance is algae bloom and no action was needed.