the Saw Kill and its tributaries at that time to generally be healthy. There were occasionally surges of coliform bacteria near the Bard wastewater treatment plant and on the tributary flowing from behind the Orchard Hill plant, but those did not seem to be a regular trend. Dissolved oxygen levels, important to aquatic life in the stream, remained within normal limits. In 2004 Dutchess County's planning department did sampling of its own as part of a countywide inventory of water resources. The Saw Kill was found to have the second highest nitrate concentration in the county after Fishkill Creek and the highest phosphate concentration. The report's writers speculated that that may have occurred because the sampling sites were below the wastewater treatment plants that discharge into the stream. Three years later New York's Department of Environmental Conservation (DEC) classified the entire Saw Kill as a Class B stream in its water quality report on the state's waterbodies. That means it can be used for swimming, boating, angling and other recreational purposes, as well as for drinking if suitable precautions are taken. While a 1998 macroinvertebrate study near the stream's mouth had found the Saw Kill to be "slightly impacted", perhaps by non-point source insecticide and fertilizer use, it was not impaired and could fully support aquatic life. Bard initiated a renewal of the earlier citizen sampling project in 2016. Volunteers sample the stream at 13 different locations, some of which have been used in other studies, and those samples are tested for Enterococcus. Those results are posted in real time on the Riverkeeper website along with data from the Hudson and its other tributaries. Biology In 1998 a Bard graduate student, in conjunction with the Institute of Ecosystem Studies in nearby Millbrook, studied the biotic effect of land use in the Saw Kill watershed. She compared the populations of pollution-intolerant insect species such as mayflies, caddisflies and Tanytarsini midges with more pollution-tolerant fly species, and other species such as leeches and snails with greater tolerance. Her results led her to agree with earlier research on the stream's chemical profile suggesting that residential use had a greater negative impact on the water than farming. Above Annandale and north of the village of Red Hook, DEC stocks the Saw Kill with brown trout, and some brook trout, every year, for anglers. Other than the stream south of the Red Hook Town recreation