skip to Main Content

VDH Expands Advisory Area for Harmful Algae Bloom in North Fork

The Virginia Department of Health has issued a Harmful Algae Bloom (HAB) advisory for a 8-mile section of the North Fork after detecting cyanobacteria toxins within algae mat material found at three sites—one at Lower River Road in Tom’s Brook, one at Bethel Road and the other at South Holliday Street in Strasburg.

Click here to read VDH’s most up-to-date advisory for the North Fork

 People and pets should avoid contact and accidental ingestion of cyanobacteria mats anywhere in the river.

Toxins found in these mats of algae can cause skin irritation and gastrointestinal problems for humans.  If ingested, toxins from cyanobacteria can be lethal to pets and other animals.

Algae on the North Fork near Bethel Road- 7/22/21

While the advisory covers the section of river between the three affected sites, Friends has been receiving reports of mat-like algae in the North Fork outside of the sampled locations.  If you see an algal mat like the one above do not enter the river, and keep your pets away.  Not all mats are toxic, but when in doubt, stay out!

For more detailed images and information from the CDC regarding cyanobacteria:
Click here for the CDC’s Cyanobacteria FAQs Page
Click here for Information for Pet and Livestock Owners from the CDC

You Can Help!

Help Friends get a clearer picture of the scope of this problem and elevate your findings to our partners by getting involved with our Algae Watch initiative. When you find a suspected algal bloom in the North Fork, take a photo and send it to us at
Please include the location of your photo and any other observations you have.
(e.g., wildlife, fish, odor, litter, river flow, etc.)

Click here to see our Algae Watch map with photos collected so far.