Principal Objectives & Design
The principal objectives of the New York Project were to:
- Measure specific environmental variables that statistically relate aquatic ecosystem structure and function to land use, BMP implementation, and other watershed inputs or factors.
- Measure chemical, physical, and biological factors that can be used to evaluate or indicate the occurrence and/or source of selected chemical and biological aquatic contaminants.
- Provide a baseline data set of biological indicators and ecosystem-level variables and for assessing water quality improvements and aquatic ecosystem responses resulting from on-going and historical land cover/use change, BMP implementation, restorations, and mitigations.
The project was designed as a six-year study (2000-2005) divided into two distinct three-year phases. Sixty stream sampling stations distributed among the major sub-basins of the principal source watersheds (East of Hudson River, EOH, and West of Hudson River, WOH) in Phase I. The 60 sampling stations were designated as either a “targeted” (n=50) or “integrative” (n=10) sampling site depending on the location in the watershed and type and intensity of variables being measured. Targeted stations occurred throughout the watersheds on streams of varying sizes. Integrative stations occur sufficiently downstream to integrate the effects of land use and other factors on a given project element or task under study over a large portion of the watershed.
Site selection criterion was to capture the range in land covers/uses across geologic and soil characteristics of all NYC source watersheds. Secondary site selection criteria included ongoing or future BMP implementation, presence of U.S. Geologic Survey (USGS) stream gaging stations, and the feasibility of studying the various study components. Sampling stations on eight reservoirs were also established in Phase I.
Phase II (2003-2005) of the project established 48 new (differing from Phase I) stream sites and four new reservoir sites. Twelve of the Phase I stream sites and three existing reservoir sites were retained to maintain continuity between phases and provide a measure of inter-annual variability. Phase II work builds upon Phase I results by sampling other important tributaries and focusing sampling effort to refine any ambiguous results from the Phase I effort.
The project is designed as a broad synoptic survey repeated annually, rather than as a highly targeted, spatially narrow survey with a high degree of repetition in each year of study. Sampling is conducted primarily in the late spring, summer, and early fall; however, winter sampling is conducted as part of one study task.