Harmful Algal Bloom
Reports of HABs in Nevada
With warmer weather and abundance of water, we may be seeing an increase of possible Harmful Algal Blooms (HABs). Harmful algae can produce toxins that hurt people, animals, and the environment. There were multiple reports of HABs in 2024. Lake Mohave still had active HABs, carrying over into early 2025 but all advisories have been lifted.
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2024- 2025
Active HAB Reports
Tips and Information about HABs
Signs that there may be an HAB in the water:
- The water smells rotten
- The water looks like paint
- Large mats or scums are floating on surface
- There are bright colors like blue, green, white, brown or red
The Nevada Division of Public and Behavioral Health (DPBH) is working with Nevada Division of Environmental Protection, Nevada State Parks and the Nevada Department of Wildlife to ensure the health and safety of Nevadans and their pets who may visit locations where a Harmful Algal Bloom (HAB) has occurred.
If a HAB is suspected, individuals should take the following precautions:
- Do not allow pets to play in or drink water during a bloom
- Do not swim or play in water with a bloom
- Do not drink, cook with or wash dishes with affected water
People exposed through direct skin contact, ingestion or inhalation may experience irritation of the skin, eyes, nose, throat, and/or respiratory tract. Symptoms to look for include:
- Rashes, hives, or blisters
- Runny nose, sore throat, asthma, or allergic-like reactions
People exposed through ingesting cyanotoxins may experience:
- Abdominal pain
- Headache
- Neurological symptoms
- Vomiting
- Diarrhea
- Liver damage and/or kidney damage
For more information and tips about HABs visit Environmental Health | The Office of State Epidemiology. Individuals who believe they may be experiencing symptoms of exposure to algal toxins should contact their local health care provider or contact the Poison Control Center: 1-800-222-1222.
Dashboard
To keep current with advisory recommendations, click here to access our dashboard
Previous HAB Reports
2024
There were sixteen reports of HABs the summer/fall of 2024.
Virginia Lake
Eagle Valley Reservoir
Wild Horse Reservoir
South Fork Reservoir
Big and Little Washoe Lakes
Weber Reservoir
Stillwater National Wildlife Refuge
Lahontan Reservoir
Lake Mohave – Eagle Wash Cove, Placer Cove, and Morning Star Cove
Chimney Reservoir
Nevada Beach Pond
Sheep Creek Reservoir
Lake Mohave – Eagle Wash Cove, Placer Cove, and Morning Star Cove
2023
There were four reports of HABs the summer of 2023.
Washoe Lake
Lahontan Reservoir
Wild Horse Reservoir
South Fork Reservoir