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Stream Biomonitoring

Overview of the Program

New York State's biological monitoring program began in May of 1972 as a result of the 1972 Federal Water Pollution Control Act Amendments. The main objective was to evaluate the health of New York's rivers and streams through the analysis of macroinvertebrate communities.

Benthic macroinvertebrates are larger-than-microscopic invertebrate animals that live in and on stream bottoms. Freshwater forms are primarily aquatic insects, worms, clams, snails, and crustaceans. Analysis of these benthic communities is a reliable and cost-effective approach to water quality monitoring. Here are a few reasons why they are used in NYSDEC's Statewide Waters Monitoring Section:

  1. they are abundant in most streams,
  2. they are relatively easy and inexpensive to sample,
  3. they are sensitive to environmental impacts,
  4. they are less mobile than fish, and thus cannot avoid discharges,
  5. they are indicators of overall, integrated water quality, including synergistic effects and substances lower than detectable limits, and
  6. they are able to detect non-chemical impacts to the habitat, such as siltation or thermal changes.

The Stream Biomonitoring Unit assesses water quality by collecting samples of aquatic macroinvertebrates from streams and rivers. In streams that are wadeable, the collection is done by means of a kick sample, as is shown in the photograph. Once a sample is collected it is sorted and identified in the laboratory under a microscope to determine the types of organisms present and their tolerances to pollution. The results are entered into a database and used to make an assessment of the water quality of the stream. In the end, the Department uses the Unit's assessment to determine whether or not the waterbody meets its designated uses.

If you would like to contact the Stream Biomonitoring Unit, send an e-mail to aquatics@gw.dec.state.ny.us

Quality Assurance Work Plan

Introduction to the QA Work Plan

This document was prepared to meet Quality Assurance/Quality Control requirements for an existing environmental monitoring program. It documents the standard operating procedures and quality control methods of the Stream Biomonitoring Unit of the New York State Department of Environmental Conservation. It was originally prepared using the 1983 Guidance Document issued by the U.S. Environmental Protection Agency's Office of Water Regulations and Standards, and utilizes the format provided in the Guidance Document.

Quality assurance is the documentation of methods and standard operating procedures to insure uniformity of methods and accuracy of data. Quality control is a system of maintaining standards through audit, review, and corrective procedures.

The present document represents the third update of the Quality Assurance document, first completed in 1988, and updated in 1991 and 1996. Changes incorporated into this update include:

  • methods for assessment of water quality using diatoms
  • methods for assessment of water quality using fish
  • adjustments for intermittent streams
  • updated methods for assessing lakes and large rivers
  • additional community types for Impact Source Determination
  • updated levels of concern for some contaminants
  • updated tolerance values for some species
  • updated species list and identification reference list