BYNUM - Jeannie Ambrose wasn't expecting to find much Saturday as she and about 10 other volunteers hunted insect larvae and other creatures in the shallows of the Haw River.

Ambrose, 58, of Pittsboro looked under palm-size rocks for snails, leeches and other pollution-sensitive macroinvertebrates that the Haw River Watch volunteers track to gauge the river's water quality. Her expectations were lowered by last week's heavy rains.

"I'm not sure what we're going to find," Ambrose said just before reacting with glee at the sight of a snail. After placing the snail in a white tub of water, Ambrose said, "Let's see if we can find some more things."

Soon enough, the volunteers have filled their tubs with caddisflies, mayflies, water pennies, stoneflies, sow bugs, midge flies, crane flies and leeches -- some barely visible to the naked eye.

The Haw River Watch project is sponsored by the Haw River Assembly, a nonprofit group that protects the Haw River watershed. Four times a year, River Watch surveys the river's aquatic insect life to track its health over time.

Cynthia Crossen, Haw River Watch coordinator, explained that textile mills used to line the Haw River and discharge pollution into the waterway. "People in Saxapahaw used to say, 'I know what color they're dyeing today,' because the water was green or blue," Crossen said.

Now, those industrial polluters have been replaced by other threats to the river's water quality, such as runoff from housing developments and construction sites, pesticides from homeowners' lawns, and oil from cars that seeps down stormwater drains.

Volunteers lugged the creatures they'd found to the Bynum Ruritan building. Soon the room was buzzing like a middle-school science class.

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