In April 2019, the Environmental Integrity Project and the Shenandoah Riverkeeper conducted a study that showed only 19% of farmers in Rockingham and Augusta counties were fencing their waterways to keep out livestock.
Through Google Earth aerial photographs and online tax maps, 1,676 livestock farms with rivers or streams in Augusta and Rockingham were studied. Of those farms, only 321 had fencing.
The results sparked the Virginia Department of Conservation and Recreation to do some digging, and the agency discovered the EIP and Shenandoah Riverkeeper had been studying any stream that appeared to be channelized instead of streams that flow year-round within the Chesapeake Bay Watershed — which the DCR is charged to do.
“That’s one of the reasons why we conducted our study, because when we saw what the EIP were, it was quickly realized that they were not limiting their scope to perennial streams and so it didn’t really inform us as to what we stood in terms of our progress with perennial stream, which we are charged to protect,” said Darryl Glover, director of the soil and water conservation division for DCR.
Throughout 2019, Glover said the department studied Rockingham County specifically due to it having the second highest number of cattle in the state based on the last agricultural census.
The Rockingham County Stream Exclusion Pilot Study identified all parcels in the county that contained a pasture within 200 feet of a perennial stream and classified the parcel based on the presence of evidence of: a perennial stream flowing through the pasture, livestock present on the pasture and livestock successfully being excluded from all areas within 35 feet of a perennial stream.
Concluding the study in December, the Virginia DCR found that of the 1,023 parcels with livestock in the county found through the 2018 National Agriculture Imagery Program, 41% successfully excluded livestock from perennial streams within the Chesapeake Bay Watershed.
“To get to 41% from the study, between 39% and 41%, I think it’s notable progress,” Glover said. “Granted there is a lot more that needs to be done, but I think we have seen that farmers will participate if the resources are made available.”
Of the parcels that did not exclude livestock, there were 604 out of 1,023, or 59% of parcels identified through the 2018 National Agriculture Imagery Program.
How The Study Was Conducted
Looking into more than 1,000 parcels with livestock is a lengthy process, which led the Virginia DCR to combine several sources of datasets to compile information.
Based on the study’s report, the initial study area was defined for all parcels containing pasture within 200 feet of a perennial stream in Rockingham County. By using the Virginia Base Mapping Program Hydrography Dataset, the department was able to classify either perennial or intermittent streams by comparing various tools.
Once the study area was defined, the parcels were reviewed manually against four sets of Virginia Base Mapping Program imagery collected from 2002-2018 and one set of National Agriculture Imagery Program from 2018.
Grazing livestock and fencing can occasionally be visible in the imagery used due to the color it presents, but fencing within dense trees or tree lines can be more difficult to determine.
“Where the presence of livestock was evident and evidence of exclusion fencing was not present, the conclusion was drawn that livestock are not being successfully excluded from the stream. Where there was evidence of livestock and an exclusion barrier was evident, the conclusion was drawn that livestock are being successfully excluded from the stream and an approximation of the location of fencing was digitized for reference only,” the study reports.
The results from the pilot study shows a workflow that can be repeated, along with showing quantitative results.
“As expected due to the investment in stream exclusion [best management practices] by the Commonwealth of Virginia, the percentage of stream exclusion increased in each successive year reviewed,” according to the report.
Imagery reviewed from 2002 showed only 24.2% of 1,162 parcels with livestock had exclusion fencing. While the number of parcels with livestock has fluctuated over time, the pilot study shows a steady increase of parcels with livestock excluded from perennial streams from 2002 to 2018 — something Glover sees as a good sign.
What The Study Shows
Since late 2012, Glover said Virginia has spent $97 million in an effort to offer 100% exclusion cost reimbursement that has resulted in nearly 2,400 sites getting fencing exclusion installed or underway.
“There are still about 100 [sites] that are under construction,” he said.
With the increase in parcels with livestock exclusion, Glover said most operators understand that keeping a herd out of streams is not only healthier for the herd, but reduced the amount of nutrients and pathogens from animal feces making its way to the Chesapeake Bay.
Moving forward, Glover said it would take “considerable resources” to accomplish the goals outlined by the Chesapeake Bay Watershed Implementation Plan to reduce phosphorus, nitrogen and sediment loads to the bay by 2025.
“If resources remain available, we can make considerable progress,” he said.