With spring in full swing and temperatures on the rise, Californians are spending more time in the state’s many waterways. But the warm weather may also create a ripe environment for harmful algal blooms to grow and flourish in lakes, rivers and streams.
Because of the greater risk during the summer months, the State Water Resources Control Board and the eight regional water boards perform pre-holiday freshwater harmful algal bloom assessments at some of the most popular recreational waterbodies prior to Memorial Day, Fourth of July and Labor Day long weekends.
The Water Boards’ HAB webmap has been updated today with assessment details to provide the public with recreational recommendations for waterbodies across the state before the Memorial Day weekend. (There are no bodies of water in Lassen County on the map.)
The public should be aware that current waterbody recreational recommendations may vary due to high flows or colder temperatures this spring season.
The State Water Board asks the public to be mindful of freshwater HABs, as they can cause illness and are especially harmful to children and pets. To learn how to stay safe, report a bloom, and track multiple blooms statewide, visit the Habs web portal.
Many different types of algae can cause harmful algal blooms. However, three types —cyanobacteria, dinoflagellates, and diatoms—cause most blooms that make people and animals sick.Most harmful algal blooms are formed by cyanobacteria, small microbes that live in nearly every habitat on land and in the water. Higher water temperatures, slow moving water, and excessive nutrients cause cyanobacteria to rapidly multiply and form these harmful blooms that can produce toxins. They can be found near the surface of lakes and reservoirs in a variety of colors, such as green, white, red or brown, and may look like thick paint floating or small flakes on the water.
Cyanobacteria can also grow as mats attached to rocks, sand, cobbles, bedrock or other plants at the bottom of a water body. Mats can detach and float to the surface of the water and strand along the shorelines.
An image of a harmful algal bloom.Because cyanobacteria can produce toxins, they have the potential to harm the environment, people, pets, wildlife or livestock. Dogs and children are most likely to be affected because of their smaller body size, increased potential to swallow water while swimming, and tendency to stay in the water longer. Recreational exposure to cyanobacteria and associated toxins can cause eye irritation, skin rash, vomiting, diarrhea and cold and flu-like symptoms.
Dogs are especially susceptible because they tend to drink while in the water and lick their fur afterward, increasing their risk of exposure and illness. Symptoms in animals include vomiting or diarrhea, lethargy, abnormal liver function test results, difficulty breathing, foaming at the mouth, muscle twitching, and sometimes death. The Office of Environmental Health and Hazard Assessment has a fact sheet to help inform dog owners.
Here’s another image of a harmful algal bloom.Safety tips
The California Water Boards recommend that people follow these safety tips to practice healthy water habits while enjoying the outdoors this summer at local lakes, rivers or streams
- Heed all instructions on posted advisories, if present.
- Avoid algae and scum in the water and on the shore.
- Keep an eye on children and pets.
- If you think a harmful algal bloom is present, do not let pets and other animals go into or drink the water or eat scum/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 harmful algal bloom is present.
Get medical treatment immediately if you think that you, your pet, or livestock has gotten sick after going in the water. Be sure to alert the medical professional to the possible contact with cyanobacteria.
Also, make sure to contact the local county public health department. To report a bloom or a potentially related human or animal illness, do one of the following
Enjoy the summer months and beautiful waterways California has to offer. But remember, when in doubt, keep out.
For more information about HABs, visit: California Harmful Algal Blooms Portal.
