 We just can't confirm that scientifically at this time. Now, unrelated to the E. coli outbreak, the upper section of the North Anna branch of Lake Anna in Louisa County remains under a swimming advisory due to a harmful bacteria bloom. Mike Murillo, WTOP News. We've just about reached the 4th of July. Folks are anxious to get out of town, those who haven't done so yet. AAA anticipates this week will be the busiest July 4th week ever.