Contact:
Ralph Bednarz 517-335-4211
Agency:
Environmental Quality
In 1997, the Department of Environmental Quality (DEQ) completed a report entitled "A Strategic Environmental Quality Monitoring Program forMichigan's Surface Waters" (Strategy). This Strategy describes the monitoring activities that are necessary for a comprehensive assessment of water quality inMichigan's surface waters. One component of the Strategy is the continuation of a statewide ambient water quality monitoring program forMichigan's inland lakes.
Historically, the Department of Environmental Quality (DEQ) and the Department of Natural Resources (DNR) monitored water quality in Michigan's lakes and streams. In 1973 the former DNR began systematically inventorying and sampling lakes to document trophic conditions as well as to obtain general baseline water quality information. In 1979, U.S. Environmental Protection Agency (EPA) funds were awarded to Michigan to expand the lakes monitoring effort and an ambient water quality monitoring program was initiated to sample and classify 730 public access lakes across the state. In 1998 with the support of Clean Michigan Initiative (CMI) funds the Lake Water Quality Assessment (LWQA) monitoring program was implemented in cooperation with the U.S. Geological Survey (USGS) - Michigan District as part of the DEQ's Strategic Environmental Quality Monitoring Program for Michigan Surface Waters.
The LWQA monitoring program continues the ambient water quality monitoring effort initiated in 1979 for public access lakes across the state. The primary objectives of the LWQA monitoring program are:
Determine the trophic conditions of the inland lakes in the state
Identify waters that are high quality, as well as those that are not meeting water quality standards
Determine whether inland lake water quality is changing with time
Identify emerging problems through inland lake quality assessments
Support DEQ watershed and lake management programs for protecting inland lake quality in the state
Lakewater quality assessment surveys are conducted during spring turnover and summer stratification periods. The surveys are coordinated with the DEQ Water Bureau's watershed permitting cycle. Water quality parameters monitored include nutrients (various forms of nitrogen and phosphorus), chlorophyll a, water clarity (Secchi depth), dissolved oxygen, water temperature, specific conductance, pH, alkalinity, hardness, and major ions such as calcium, magnesium, sodium and chloride.
The LWQA data are used to identify lake trophic status, regional lake quality characteristics, and changes in lake quality conditions. These data are used to satisfy federal CWA Sec. 314 and 305(b) requirements, determine water quality standards and designated use impairments, and to support watershed and lake management programs for protecting inland lake quality. The LWQA monitoring program is integrated with the citizen volunteer Cooperative Lakes Monitoring Program (CLMP) to increase monitoring effectiveness.
As part of the LWQA monitoring program, the USGS under the direction of the DEQ is exploring the feasibility and practicality of using remote sensing satellite imagery for lake water quality assessments that will enable the DEQ to estimate productivity of un-sampled inland lakes statewide. Statistical models and an on-line application tool for predicting lake water clarity and chlorophyll content were developed and tested with LWQA and CLMP data.