Dogs sniff out pollution along Great Lakes

In the town of Bridgman, Mich., investigators Sable and Kenna sniff samples from storm water drains near a beach. Sable is a 10-year-old German Shepherd. Kenna, a Golden Retriever, is 2.

The dogs have been trained to sniff out polluted water, says Karen Reynolds, co-founder of Environmental Canine Services.

“And if they smell any contamination that indicates human source bacteria, then they will give an alert,” she says. “Sable barks when he smells that and Kenna will sit.”...