As a former Boy Scout, Bill Knapp Jr. of Raleigh, N.C., respects nature and loves volunteer work. Thanks to the city’s Adopt-a-Stream program, his passions intersect as neatly as a lateral and a sewer main.Knapp, 82, a retired veterinarian, just completed three years as chief watchdog of a 2-mile stretch of Crabtree Creek. Thanks to his Boy Scout roots, he found great satisfaction in strolling the banks while looking — and sniffing — for pollution. “Being in Boy Scouts taught me about nature and the outdoors,” Knapp says. “The older I become, the more I appreciate nature. We’re dependent on
