Updated: 4/4/2023. A Brown Water Advisory has been issued for Hilo bay on Hawai‘i. The recent heavy rains is continuing to affect the coastal waters of Hilo Bay. The public is advised to stay out of flood waters and storm water runoff due to possible overflowing cesspools, sewer, manholes, pesticides, animal fecal matter, dead animals, pathogens, chemicals, and associated flood debris. Not all coastal areas may be impacted by runoff, however, if the water is brown stay out. Continue to practice good personal hygiene and follow-up with your primary care physician if you have any health concerns.