9/22/2012 7:00 AM
By Andrew Jenner Virginia Correspondent
TENTH LEGION, Va. — Detailed monitoring and analysis of water quality in the “showcase” Smith Creek watershed will help scientists and conservation agencies design more effective programs to protect streams and rivers in the wider Chesapeake Bay watershed, according to members of the Smith Creek Partnership who met last week.
One of three showcase watersheds in the bay watershed, Smith Creek has received extra federal conservation money over the past two years for water quality protection. The effort has met with considerable success so far, said Richard Fitzgerald, an NRCS agronomist and coordinator of farm conservation efforts in the watershed.
Before the designation, he said, there were just two conservation cost-share projects in the 65,000-acre watershed in Rockingham and Shenandoah counties. By the summer of 2011, that number had risen to 22, and by the end of the 2012 fiscal year in July, 44 contracts were in place, with numerous others in the planning process.
In the 2012 fiscal year alone, public spending on these projects was nearly $500,000, an amount matched by farmers who have participated in the various cost-share programs.
“That’s huge,” Fitzgerald said, adding that his colleagues have contacted or conducted farm inventories for 250 landowners within the watershed, about half the total number of large landowners.
The contracts signed to date include 11 waste storage facilities, more than 2,500 acres of nutrient management and more than four miles of fencing along streams and in pastures.
At the Smith Creek Partnership’s meeting last week, U.S. Geological Survey hydrologist Ken Heyer spoke about the intensive monitoring he is overseeing in the watershed. The results of that work will allow everyone to measure and evaluate the effect of all the BMPs that have recently been installed along Smith Creek. Heyer said he plans to begin publishing preliminary results in the upcoming year.
In addition to routine sampling at existing gauge stations, Heyer has conducted “spatial sampling” several times over the past year. Each time, water samples are taken at about two-mile intervals along the stream and its tributaries, as well as springs that feed them, over a one- to two-day period. Heyer’s team conducts various measurements on each sample, including “isotopic” analysis of nitrates — the most common chemical form in which nitrogen occurs in Smith Creek — to determine their origins.
Because different nitrates sources have different “isotopic signatures,” this technique can distinguish between nitrogen pollution coming from commercial fertilizers and livestock manure.
Heyer, who also monitors water quality in Maryland’s Upper Chester River, another USDA showcase watershed, noted that his sampling shows that nitrogen pollution there comes mainly from commercial fertilizers. Not surprisingly, he said, nitrogen pollution in Smith Creek appears to be largely coming from livestock manure or failing septic systems.
That finding, he continued, indicates that the waste storage, livestock exclusion and pasture management practices, among others targeted toward reducing manure runoff, stand to have significant effect in the watershed.
“I think we’re on track, and I think that’s a good thing,” Heyer said.
In the coming year, Heyer and his colleagues will begin similar analysis of stream sediment, hoping to determine which major land uses — forest, pasture, cropland — contribute the most sediment to the watershed. That information will also be used to refine the outreach being conducted by the NRCS and other conservation agencies partnering in the effort.
He also said that the detailed monitoring will provide a better understanding than ever before of the specific effects that various land uses and BMPs have on water quality. These findings, he said, stand to influence conservation efforts throughout the bay watershed.
According to Fitzgerald, the major lesson to date in the Smith Creek watershed is that “voluntary programs still work. But you’ve got to commit enough resources for financial and technical assistance.”
Fitzgerald said an ongoing challenge to the effort is that just one engineer is now available to review BMP projects in a 13-county area including the Smith Creek watershed.
In the upcoming year, Fitzgerald and others will continue working with landowners to install more BMPs in the watershed, refining their strategies as they go based on the water quality study being led by Heyer.