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Water Chemistry

Contact: Jeff Varricchione 517-342-4557

EGLE's report, “A Strategic Environmental Quality Monitoring Program for Michigan’s Surface Waters,” (Strategy) identified four major goals of the Water Resources Division and listed individual objectives within each of the Water Resources Division Programs.  The Strategy was written at a time when resource constraints had forced funding and staffing for water quality programs to decrease considerably.  A Strategy Update was written in 2005 after those resource constraints were alleviated with annual appropriations of Clean Michigan Initiative funds, allowing the Strategy to be fully implemented.  Another Strategy Update was written in 2017.  Beginning in 2020, the Renew Michigan Fund will be providing funds to help implement the Strategy.

The Strategy has four major goals:

  1. Assess the current status and condition of waters of the state and determine whether water quality standards are being met.
  2. Measure spatial and temporal water quality trends.
  3. Evaluate the effectiveness of water quality prevention and protection programs.
  4. Identify new and emerging water quality problems.

Within each goal are specific objectives that are reached through Water Resources Division monitoring activities, including the Water Chemistry Monitoring Program.  The primary objectives of the Water Chemistry Monitoring Program are to: (1) identify the chemical character of surface waters of the state and relate characteristics to Michigan’s Part 4 rules, Water Quality Standards, when applicable; and (2) determine whether the chemical character of surface waters of the state are changing over time.

The water chemistry element consists of several components that, in combination, provide data necessary to achieve these objectives.  These include:

  • Fixed station trend sites (Saginaw & Grand Traverse Bays, connecting channels) (note: annual fixed station trend monitoring of 31 tributaries to the Great Lakes ended in 2013);
  • A statewide water chemistry status and trends program began in 2005 using a probabilistic sampling design with 250 “PROB” sites total and 50 sites monitored per year on a rotating, 5-year cycle;
  • Watershed surveys (consistent with the 5-year basin cycle);
  • Issue sites (TMDLs, nonpoint source issues, statewide mercury assessment, etc.); and
  • Annual grants to local governments.

Water samples generally are analyzed for nutrients, conventional parameters (temperature, conductivity, suspended solids, pH, dissolved oxygen), total mercury, and trace metals (cadmium, chromium, copper, lead, nickel, zinc).  Historically, a much smaller number of samples were analyzed for organic contaminants such as PCBs and base neutrals.  Other parameters may be included as appropriate at specific locations.  Data are reviewed periodically to determine whether additional parameters should be added, removed, or analyzed at a greater or lesser frequency.

All water chemistry data are entered into the (Water Quality Exchange WQX) (formerly STORET).  Data are then accessible to the public through the (Water Quality Portal WQP).   WCMP data (e.g., statewide water chemistry status and trends; fixed station trends) are summarized in reports produced by the WRD (see links, below).  Data collected as part of the 5-year watershed surveys will be summarized in watershed reports.  Data collected as part of TMDL sampling will be summarized in individual reports prepared for each applicable waterbody.

Data are available upon request.  Reports are listed below.

Moving forward, requests to have EGLE's Water Resources Division (WRD) monitor a particular waterbody can be made via its targeted monitoring request process.  WRD annually evaluates all the requests it receives and, in light of available funding, staff time, and demonstrable need for the data, it prioritizes which requests it can fulfill.  For more information on the targeted monitoring process, contact Jeff Varricchione at 517-342-4557 or

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