How can I protect myself from potential harmful algal bloom?
If you see a potential harmful algal bloom, there are things you can do to protect yourself, family and pets. There is no way to tell if an algal bloom is toxic just by looking at it. The California Water Boards recommends that you practice Healthy Habits while enjoying the outdoors at your local lake, river, or stream.
Healthy Water Habits
- Heed all instructions on posted advisories if present
- Avoid algae and scum in the water and on shore
- Keep an eye on children and pets (dogs)
- If you think a HAB is present, do not let pets and other animals go into or drink the water, or eat scum and algal accumulations on the shore
- Don’t drink the water or use it for cooking
- Wash yourself, your family, and your pets with clean water after water play
- If you catch fish, throw away guts and clean fillets with tap water or bottled water before cooking
- Avoid eating shellfish if you think a HAB is present
How do I identify harmful algae?
There are many types of algae. Only some are capable of producing toxins. Several guidance documents are available to aid in the identification of algae thereby distinguishing toxic and non-toxic algae - the guides below will get you started.
Algae can be identified by microscope or by visually observing algae in the field. Note that some algae are difficult to distinguish in the field and will also require observing an algae sample under a microscope. Before you head to a potential harmful algal bloom ensure that your health and safety is protected, see this guide.
- Algae versus Cyanobacteria
- Surface Water Ambient Monitoring Program (SWAMP), Visual Guide to Observing Blooms
- US Geological Survey, Field and Laboratory Guide to Freshwater Cyanobacteria Harmful Algal Blooms Pages 4-15 provide photos of harmful algae and of non-harmful green algae and aquatic plants. Microscope images are also included starting page 16.
- Key to Algal Phyla/Classes of California
- Western Washington University, Freshwater Algae in Northwest Washington, Volume I, Cyanobacteria
- University of New Hampshire, PhycoKey: An Image-Based Key to Algae (PS Protista), Cyanobacteria, and other aquatic objects
- Northern Kentucky University, Field guide to algae and other “scums” in ponds, lakes, streams and rivers
How can I report a bloom, or an animal illness or human illness related to a bloom?
Reporting a harmful algal bloom or an animal or human illness associated with exposure to a bloom helps authorities understand where problems are occurring and to respond appropriately.
- Freshwater Bloom Incident Form
- Including a related animal or human illness
- bloomWatch App
- Available as a free download (Android, iOS)
- Report a red tide or other unusual marine sighting
- Call: 1 (916) 341-5357
- Call toll free: 1 (844) 729-6466
- Email: CyanoHAB.Reports@waterboards.ca.gov