The DNREC Recreational Water Program monitors bacterial water quality at established sampling sites throughout the state from May through September. If bacterial sampling results exceed state standards, DNREC issues swimming advisories for Atlantic Ocean beaches, as well as for Delaware Bay beaches south of and including Lewes Beach and for Lake Como in Smyrna.

The purpose of these swimming advisories is to alert the public that an elevated risk of illness from recreational water contact may exist, so that individuals may make informed decisions based on their medical history and personal tolerance for risk.

For other waterbodies in the state, DNREC may monitor bacterial water quality but does not issue a swimming advisory each time the standard is exceeded. Instead, DNREC has issued a permanent swimming advisory caution for waters including Delaware’s Inland Bays (Rehoboth Bay, Indian River and Bay, Little Assawoman Bay and the portion of Assawoman Bay located in Delaware) and for Delaware Bay beaches north of, but not including, Lewes Beach.

The purpose of the swimming advisory caution is to alert the public of the potential illness risk from recreational contact with these waters, particularly for persons with certain medical conditions or compromised immune systems. The illness risk may be higher during and after rainfall, and if a person’s head is submerged during water contact.

Sources of Bacteria

DNREC samples waterbodies for Enterococcus bacteria, an indicator of other bacteria and viruses from the intestines of humans and other warm-blooded animals. These pathogens may cause human illness, most commonly gastroenteritis, after contact with natural waters.

Enterococcus bacteria can come from natural and human sources. Scientific studies show wildlife to be a major contributor. Wildlife, and the Enterococcus bacteria they produce, are part of the natural ecosystem of many waterbodies throughout the state.

Some waterbodies aren’t regularly flushed out by tides, so Enterococcus bacteria lingers in the waters. Enterococcus levels may be higher following rainfall.

It is recommended that you consult with your healthcare provider before you swim in any natural water body, especially if you have certain medical conditions or a compromised immune system.

The Swimming Advisory Caution

The swimming advisory caution does not necessarily mean that a beach is closed. It is meant to alert the public of the potential illness risk of swimming in natural waters, especially for persons with certain medical conditions or immune system issues. The decision whether to close a beach is made by the municipality or state park that manages the beach.

If you have concerns about your specific health conditions, please consult your health care provider.

For your health and safety, it is best to swim at beaches with lifeguards. Water quality at all guarded public beaches is tested regularly from May through September. DNREC recommends that you enjoy guarded beaches which are not currently under a swimming advisory.

Related Topics:  assessment, Health and Safety, outdoors and recreation, recreational water quality, testing, water quality, watershed, watershed stewardship