Director's Notes
December 2009
Sampling for Bacteria
From May to November of 2008, StreamWatch collected fecal bacteria throughout the Rivanna basin. Carried out largely by University of Virginia students, the field work involved duplicate samples collected at each of 17 sites site once per month.
This effort was part of the Land Use Study we have been working on since 2007, and was intended to determine whether bacterial levels correlated meaningfully with the presence of cattle. Other studies and common sense suggest that bacterial levels should be higher in streams where cattle have direct access, and probably also where grazing occurs near streams. But can cattle-related bacteria be meaningfully measured by methods that are practical and affordable for StreamWatch?
Bacteria data could provide clues about the relative importance of cattle impacts. But we won’t know if the data collected in 2008 are useful until the Land Use Study analyses are complete and the report is published (May 2010).