Enhanced monitoring effort in New York City’s drinking-water-supply watershed

C.L. Dow, D.B. Arscott, A.K. Aufdenkampe, T.L. Bott, L.G. Carter, J.K. Jackson, L.A. Kaplan, J.D. Newbold, and B.W. Sweeney.Stroud Water Research Center, Avondale, Pennsylvania, 19311

The Stroud Water Research Center has been monitoring stream and reservoir ecosystem health across New York City’s drinking-water-supply watershed since 2000. Baseflow sampling has involved macroinvertebrates, major ions/nutrients, dissolved organic carbon, seston, and a suite of molecular tracers at 110 stream sites. Stormflow sampling of stream chemistry has occurred at 3 stream sites. Measures of ecosystem functioning, including nutrient and carbohydrate spiraling and measures of stream metabolism have been performed at 17 of the 110 sites. Reservoir productivity measurements have taken place on 12 of the 19 lakes/reservoirs that are part of the surface water-supply infrastructure. In 2004, a pilot study was initiated involving molecular tracer source tracking to better identify sources associated with the tracers found in stream samples. Challenges faced in analyzing these data have included matters of catchment versus near-stream scale influences, relationship ‘domain’, and separating geologic influences from anthropogenic. More important has been the challenge of synthesizing data across the various tasks to provide one of the first known attempts of incorporating such a broad suite of in-stream measures collected under similar and consistent conditions as part of a water-quality monitoring effort.