Potentially harmful algae bloom in the North Fork of the Shenandoah River near Bethel Road area of Strasburg in Shenandoah County. The Lord Fairfax Health District of the Virginia Health Department is cautioning people not to swim in that area until the results of an algae test come in later this week. The algae blooms discovered at the Bethel Road area of Strasburg could be cyanobacteria, which “has the ability to put out a neurotoxin.”