| Water scientists use laundry detergent clues to detect source water issues
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Water scientists use laundry detergent clues to detect source water issues

Scientists at Beaver Water District (BWD) in Arkansas are adding meaning to the old axiom, “It all comes out in the wash.”  

BWD scientists conduct research on optical brighteners in Beaver Lake.At BWD, a regional water distribution district serving communities in northwest Arkansas, scientists in the environmental quality department are using the presence of synthetic laundry detergent chemicals to help detect human-influenced water quality problems in its source water, Beaver Lake. (Pictured right, BWD scientists conduct research on optical brighteners in Beaver Lake.)

“These laundry detergent chemicals, called optical brighteners, are used in most name-brand detergents to enhance the appearance of white and color fabrics in the presence of ultraviolet light,” said Dr. James McCarty, environmental quality manager at BWD. “While the brighteners are not known to be directly related to human health effects or environmental problems, they can indicate the presence of untreated wastewater in our source water.”

James McCartyThe detecting begins once water containing detergent drains from the washing machine into a municipal or neighborhood sewer system or home septic system. A properly-functioning wastewater treatment system will degrade most optical brighteners through time and exposure to light, said McCarty (pictured left)

“The presence of optical brighteners in a lake indicates a place where harmful nutrients and pathogens from wastewater may also be entering the lake, short-circuiting the wastewater treatment process,” he added. “If we can determine the source of nutrients and pathogens, such as failing septic systems, then we can work to provide resources and funding to fix those problem areas.”

BWD device to detect optical brightenersBWD recently built a device (pictured right) to detect and measure optical brighteners in Beaver Lake. The device pumps sample water through a fluorometer, which measures the intensity of the light frequency given off by optical brighteners at specific locations within Beaver Lake.

“While we’re still working out some kinks in the equipment and our sampling strategy, we have already seen some promising results,” McCarty said. “We have found optical brighteners in samples taken from areas of the lake shoreline with high density housing. The goal for this data is to find ways we can reduce the risk of failing septic systems on Beaver Lake, which is the water source for more than half a million people.”

The Arkansas Natural Resources Division recently initiated a septic system remediation program to help homeowners repair failing septic systems. The program offers grants and no-interest loans to homeowners within the state’s Beaver Lake, Illinois and Buffalo River watersheds.

“The reality is that it costs more to purify contaminated water,” McCarty said. 

(Photos courtesy of Beaver Water District)