We chose Schenectady County based on new maps developed from public sources representing ground water dependence and pesticide use. See the overview page for information about sources of these data. Near our state capitol of Albany, Schenectady County has a dense population that depends on ground water tapped by public water supply wells. Unfortunately, there were no monitoring wells available, and because public water supply wells are already monitored, we were restricted to sampling private wells on the periphery of the urban area where public water supply had not yet extended. In cooperation with the County’s Water Quality Coordinating Committee, The Schenectady County Conservation District recommended private land owners to approach about sampling their wells.

Like Cortland County, Schenectady County’s population center relies on a glacial / alluvial sand and gravel aquifer for its water supply, another of New York’s “primary water supply aquifers.” The Great Flats aquifer is associated with the Mohawk River. The aerial photo below shows extensive urbanization and sprawl in the eastern core of Schenectady County, and the rural area to the west and northwest. The rural area yielded most of the wells sampled, which had woods, abandoned farmland, and active hayland surrounding them.

The Schenectady County work was our second round for the State’s pesticide laboratory. With new equipment in place, detection limits for all classes of pesticides improved to 1 microgram per liter, adequate to be able to check results against drinking water criteria and most environmental standards. The State lab testing did not detect any residues of any of the 93 active pesticide ingredients examined. One sample had a trace detection of less than 0.2 ug/L (parts per bilion) of imidacloprid insecticide in an immunoassay screening test done at Cornell. Nitrate analysis by ion chromatography found that most samples were less than 1 mg/L of nitrate-N, and none exceeded 5 mg/L (as compared to recommended maximum levels of 10 mg/L nitrate-N), the best showing of all counties sampled through 2009.

The work in Schenectady County led to our third cycle Orange County work.