Wearing hip waders and arm-length rubber gloves, Drew Miller wades into the ripples of the Roanoke River, gripping a wooden-handled net.
Miller, a biologist for the Virginia Department of Environmental Quality, is soon knee deep in his work, testing the water for pollution.
To do that, he must first find the bugs, snails and worms that live along the river bottom. After scooping a load of organisms and muck into his net, Miller wades back to the shore and examines his catch.
“This guy right here is a really good indicator of water quality,” Miller says of a mayfly, just one of the samples he will take back to a state lab for testing.
Benthic macroinvertebrates – or, to the layman, river bottom bugs – are extremely sensitive to pollution, and their numbers and diversity can tell DEQ officials a lot about the health of the river.
Last month, the agency released its biennial Water Quality Report. According to bugs and other indicators, the 32 miles of the upper Roanoke River, from its headwaters in Montgomery County to where it flows into Smith Mountain Lake, are all polluted in some way.
Despite that sobering statistic – and high levels of pollution for other waterways statewide – officials say water quality is actually improving.
“Although the report shows that we continue to have water bodies that are affected by pollution, there has been considerable progress in restoring and protecting our vital water resources across the state,” DEQ Director David Paylor said in a statement with the report’s release.
Of the 52,255 miles of rivers in Virginia, 13,145 – or 25 percent – are polluted, the report found. But that’s almost certainly an under count, considering that 65 percent of the total river miles were not tested.
All 32 miles of the upper Roanoke River were subjected to tests, including ones like the bug sampling that Miller did earlier this month at Salem’s Rotary Park.
And nearly all of the lakes in Virginia were monitored; the report found that 81 percent of their acreage is polluted.
So the more you test for dirty water, it seems, the more likely you are to find it.
Bacteria and sediment
To many people, the words “water pollution” might conjure up an image of a factory dumping toxic chemicals into the river from a pipe.
While a problem in the past, that type of emission is not a major issue for the Roanoke River, said Lawrence Willis, regional monitoring coordinator at DEQ’s Roanoke office.
Toxic releases statewide have been decreasing for years, at least in part because of tougher regulation.
Today, the biggest problems on the Roanoke River are E. coli bacteria, which comes from human and animal waste, and sediment from city streets and construction sites that is washed into the river by storm water.
PCBs, or polychlorinated biphenyls, which can cause cancer and other health problems, are also a concern. Although PCBs are present in all 32 miles of the upper Roanoke River, they are in much smaller concentrations than bacteria and sediment.
Reducing bacteria and sediment can be a greater challenge for regulators than cracking down on a single dirty industry.
That’s because the so-called nonpoint source pollution can come from almost anywhere in the watershed that feeds the Roanoke River.
With E. coli, the source could be wildlife: a bear doing what bears do in the woods. Or a herd of cattle that wades into the river. Or a leaking private septic system. Or an overflowing public sewer line. Or a dog being taken for a walk along the Roanoke River Greenway.
Collectively, contamination from those sources affects 29.5 of the 32 miles of the upper Roanoke River, which passes through the cities of Roanoke and Salem and the counties of Bedford, Montgomery and Roanoke.
In recent years, improvements to the wastewater treatment plant in southeast Roanoke have reduced the amount of bacteria it releases, according to Sarah Baumgardner, environmental communications coordinator for the Western Virginia Water Authority.
And overall, the levels of bacteria in the upper Roanoke River are decreasing, said Mike McLeod, a senior environmental specialist with the DEQ.
Sediment pollution – dirt and silt carried by rain runoff from construction sites, city streets, parking lots and cultivated fields – affects 18 miles of the upper Roanoke River, according to the DEQ’s latest data.
About 57,000 tons of sediment find their way into the river each year. The silt poses the greatest risk to benthic macroinvertebrates, the river bottom bugs, by coating the submerged rocks they like to live under.
Environmental officials have determined that the sediment level should be reduced to no more than 21,079 tons a year to maintain a healthy aquatic community.
Later this year, the DEQ will release an implementation plan to achieve that goal.
Officials are planning a community-based approach. “There are lots of things landowners can do, people with yards and stream-side property,” said Mary Dail, a DEQ environmental scientist. “It’s not just the farmers and the big producers.”
For example, allowing trees and vegetation to grow along waterways can reduce the erosion that dumps sediment into the river.
Public buy-in for such a plan may well be enhanced by the expanding Roanoke River Greenway project. Whether they use the greenway to walk, run or bike, countless Roanoke Valley residents have been exposed to river views that previously were out of sight and out of mind.
“It makes a tremendous difference, just with the public awareness,” said Bill Tanger, chairman of Friends of the Rivers of Virginia, a statewide coalition of groups dedicated to river protection and conservation.
“People are able to see things that need fixing. They start asking questions and they become more involved.”
The same could hold true for Smith Mountain Lake, where a growing recreational population has been exposed to high bacteria levels that have on occasion prompted the state health department to issue swim advisories.
About 1,000 of the lake’s 19,820 acres are not suited for recreational use, according to DEQ data. The entire lake is considered polluted, mostly by PCBs.
For years, the health department has advised a limited diet of fish taken from waters affected by PCBs.
Statewide monitoring
The DEQ Water Quality Report is a massive and highly technical compilation of data that is required by the federal Clean Water Act, a fundamental law passed four decades ago.
Every two years, Virginia tests about a third of its water bodies on a rotating basis, taking six years to complete a full monitoring cycle.
Among this year’s findings:
n Of the waters evaluated, about 13,100 miles of rivers and streams, 94,000 acres of lakes and reservoirs, and 2,130 square miles of estuaries are polluted. That’s 25 percent of the rivers, 81 percent of the lakes and 79 percent of the estuaries. Bacteria and sediment were the two most common pollutants.
n About 840 river miles and 100 lake acres were added to the list of impaired waters.
n Another 260 river miles and 2,700 lake acres were removed from the list because they fully meet water quality standards.
n Statewide, more than 1,000 cleanup plans need to be developed.
While the amount of polluted river water is on the rise, state officials say that’s in large part because of more frequent monitoring and improved techniques.
To an untrained eye, there seemed to be little pollution on a stretch of the Roanoke River that passes through Salem’s Rotary Park, where Miller was gathering bug samples on a recent sunny afternoon.
A few tattered plastic bags fluttered in the breeze from the tree branches where they had become ensnared. An empty beer can bobbed in the current. A discarded milk jug lay nearby.
Beneath the surface, Miller was finding lots of life: mayflies, water penny beetles, stoneflies, caddisflies, gilled snails, Asian clams and one hellgrammite, a sinister-looking larva with pincers that it waved angrily upon being caught in the net.
“I’m seeing a pretty diverse group of bugs here,” Miller said. “It’s a pretty good sample.”
He then stored the bugs in alcohol – a small sacrifice for science – and drove them back to the DEQ lab for testing to be done this summer, after the spring monitoring season is over.
Two years from now, when the next water quality report comes out, those dead bugs will tell us something new about the health of the Roanoke River.