From the Chickens to the Crabs - The Ripple Effect: The Fate of Freshwater in the Twenty-First Century - page 64

When I met him in 2008, Dr. Robert M. Hirsch was fifty-nine years old and, as chief
hydrologist of the US Geological Survey, arguably the US government's leading water
expert. (He has since voluntarily stepped down from that leadership role to return to
his first love, hydrologic research for the USGS.) With a lithe bulk, receding dark hair,
and a bushy gray beard, Hirsch's fuzzy robustness lends him the aspect of an old-time
scientist-explorer. It's easy to picture him in a sepia-toned photograph standing next to
the legendary one-armed bearded scientist-explorer John Wesley Powell—the second
director of the USGS, and one of Hirsch's heroes.
The USGS, generally known as the Survey, was founded in 1879 to “classify the public
lands.” The only scientific bureau in the Department of the Interior, USGS had some ten
thousand employees by 2009. It plays a leading role in studying the nation's waters but
also has a broad portfolio that covers biology, geology, and geography. I noticed a pro-
nounced esprit de corps among USGSers; many of them are lifers, and even those who
have moved on to other things continue to proselytize on the agency's behalf.
On this warm June morning, Hirsch stood ankle-deep in the brown swirl of Muddy
Creek, a slim, lazy watercourse in Mount Clinton, Virginia, at the southern end of
the Shenandoah Valley. The Blue Ridge Mountains rose to the east, the Alleghenies to
the west; the verdant, gently rolling hills were planted with neat rows of corn; animals
wandered around small barnyards. There were no belching smokestacks, traffic-clogged
highways, putrid hog-waste lagoons, or noxious mounds of garbage here. It was difficult
to believe that the most toxic thing for miles was the bucolic stream we were standing
in.
In 1996, Muddy Creek failed Virginia's fecal coliform water-quality standard, viol-
ated the nitrate public-drinking-water standard, and had excessive levels of phosphorus
and sediments. It was placed on Virginia's List of Impaired Waters. A more recent report
found Muddy Creek to be suffused with “elevated nitrogen concentrations” and “fecal
bacteria.” Locally, it has been called “the most contaminated stream in Virginia.”
Muddy Creek is part of the Chesapeake Bay watershed. The creek flows into the
Shenandoah River, which merges with the Potomac, which empties into the bay. As the
water moves downstream, it picks up nutrients and toxins until it hits the Chesapeake's
ecosystem with the impact of an aquatic bomb.
“See that? That's a typical indicator of excessive nutrients,” Hirsch said, bending to
point out strands of bright green algae growing along the sides of Muddy Creek. “Hyp-
oxia—the depletion of dissolved oxygen in the water, which occurs when the algae
die—associated with agricultural runoff is a major water-quality issue. Not only here
but around the world.”
Scientists have been studying the water quality of streams like this one in the Ches-
apeake Bay watershed since the 1980s, when they began to notice large algae blooms,