Sewage contamination of waterways is a continuing world-wide problem that many people wrongly assume has been solved in places like the Severn River. Waterfront communities are aware that sewage contamination impacts recreational swimming in the Severn River, but this problem is also a potential threat to local shellfish harvesting. Many communities in the Severn watershed are not connected to regional sewer service, and individual homes rely on their own septic systems that vary greatly in quality and repair.
Leakage from these systems has contaminated local swimming beaches, leading to the threat of viral diseases such as hepatitis A as well as a variety of illnesses caused by bacteria. Excess nitrogen, much of it in the form of septic effluent transversing the water table into the creeks and river, has lead to expanding dead zones, especially in Round Bay, where no aquatic creatures can survive.
Another source of sewage contamination in the Severn is related to its intense recreational boating activity. Although sewage discharges from boats is forbidden throughout the Chesapeake region, technical problems for boaters are significant, pump-out stations are just now beginning to be easily available, and enforcement of regulations has been difficult. Summertime monitoring of sewage contamination by measuring intestinal bacteria at Severn swimming beaches is carried out by the Anne Arundel County Health Department and by the Severn River Association's Operation Clearwater. The Severn's bacterial monitoring is described in more detail elsewhere.
Response: Improved stormwater management and better maintenance of private septic systems will result in lowered coliform and enterococci counts throughout the Severn. As more stormwater is infiltrated on site, less runoff will be available to wash waste from domestic and wild animals into the River. Individual septics can be upgraded with nitrogen-reducing technology which may be subsidized by Chesapeake Bay Restoration Funds
. Additionally, prevention of boat discharge by enforcing use of pump-out stations is clearly a cost-effective way to reduce input from boaters. These measures will also lead to a reduction in nutrient input into the River since sewage is also high in nitrogen and phosphorous.