D.C. area rivers and creeks are seeing an increase in bacteria after Tropical Storm Isaias swept through the region earlier this week.

Combined sewer levels have overflowed in D.C. following Isaias, causing E. Coli levels to spike.

Anacostia Riverkeeper testing results show some unsafe E. Coli levels in the Anacostia River near the National Arboretum, Hickey Run, Yards Park, Anacostia Park and Buzzard Point.

Testing showed six areas to be high in the Potomac River, including the Washington Canoe Club, Fletcher’s Cove and Columbia Island.

In Rock Creek, seven testing sites came back as high, including the areas of Pinehurst Branch, Broad Branch and P Street Beach.

In Maryland, four of six areas in the Upper Anacostia watershed came back as over the maximum detection level, causing the riverkeeper to remind those out and about to be cautious this weekend.