Officials from the U.S. Forest Service and California State Water Resources Control Board have issued an algal mat alert for parts of the Warner Mountain Ranger District on the Modoc National Forest.
Visitors should use caution near streams that may contain toxic algal mats.
The affected sites include East Creek, near South Warner Road; Owl Creek, just above County Road 1; and Twelve Mile Creek, east of Mount Bidwell.
Algal mats can attach to streambeds, float on water, or wash ashore.
Some of these mats produce toxins that can cause illness in humans and animals. Dogs face high risk because they might drink or eat algae in contaminated water.
Visitors must follow all posted warnings. Avoid touching, swallowing, or swimming near visible algae, mats, or scum. Keep children and pets away from these areas.
Do not use creek water for drinking or cooking. Rinse off with fresh water after any contact with stream water. Anglers should discard fish waste and clean fillets with bottled or tap water before cooking.
Seek medical or veterinary care immediately if you or your pet show symptoms after exposure to algae or discolored water.
For statewide updates on harmful algal blooms, visit the California Water Boards HAB Reports Map at mywaterquality.ca.gov/habs/resources/reports-map/. Check the Modoc National Forest website at fs.usda.gov/r05/modoc/alerts for current local forest alerts and advisories.
