CIB releases water quality indicators

A new report finds water in the Inland Bays is safe to swim in 87 percent of the time. However, tributaries to the bays are too polluted for swimming nealry 40 percent of the time.

The information was gathered from data collected between 2004 and 2008.

The Center for the Inland Bays has released a one-page report on bacteria levels at 30 places around the Inland Bays. Designed to educate the public on the health of the bays, the report is the first in a series of reports on the bays’ heath.

The findings show in the well-flushed open bays, bacteria levels exceed standards 13 percent of the time. Levels in residential canals exceed levels considered safe 15 percent of the time, while in tributaries, that number jumps to 39 percent of the time.

Data in the report came from the University of Delaware’s Citizens Monitoring Program and the Department of Natural Resources and Environmental Control, said Chris Bason, science and technical coordinator for the center.  The center looked at data on entrococcus, a bacteria that indicates fecal contamination and exposes swimmers to gastrointestinal illness. 

“The tidal tributaries have more bacteria because they are in closer connection to pollution from the land, and their waters are lower in salinity.  Freshwater is more hospitable to bacteria than salt water,” Bason said.

“One of our big goals is education,” he said.  Bason cited signs along the Inland Bays that caution swimmers about a standing swimming advisory cautioning them they might become ill from the water.  “We hope to help out by providing more in-depth information to help people make an educated decision,” he said. 

Ed Whereat, University of Delaware scientist and coordinator of the Citizens Monitoring Program, said, “Bacteria levels are naturally variable and can be unpredictable at a given location.”  Studies indicate bacteria levels increase after rain and on outgoing tides in tributaries. 

One Inland Bays beach, Tower Road, has been the subject of state advisories this summer.  Its high bacteria levels could be the result of runoff from the large paved parking lot and the number of water birds that frequent it, said Bason.

Bacteria also reaches the bays through poorly functioning septic systems and runoff from urban and agricultural areas.

Bason said people can contribute to efforts to clean up the bays by cleaning up after pets, maintaining septic systems, supporting buffers for waterways and promoting pervious surfaces in developments.  The report also suggests people not feed birds and direct runoff at their homes into soil and not onto the street.   

“It all relates to the Clean Water Act and why the center is here,” said Bason.  That federal legislation seeks fishable and swimmable waterways, and bacterial levels can determine whether waters can be safely used. 

The report says scientists aren’t sure yet if water quality is improving, but they expect to see a decrease in bacteria over the coming years as a result of central-sewer installations and poultry-litter management.  Bacteria also reach water from pet waste, water birds and bay-bottom sediments.

Indicator reports are usually published as booklets, but the center plans to issue a series of one-page reports and distribute them to decision makers. They will also place them at locations where the public can read them as well, said Bason.  

 The peer-reviewed report is designed to be read by anyone, not just scientists.  

 Bason said the center plans to update other environmental indicators and expand the information they give.  One might be on clamming, he said.  There is a hard-clam landing report, but that shows how many people use the resource, and not the condition of the resource, he said.