Although 20 years of regulation brought an overall reduction in pollutant loads to the Lake Michigan basin, data indicate that pollutants still negatively affect the chemical, physical, and biological components of the Lake Michigan ecosystem. The rivers and tributaries flowing into Lake Michigan convey the contaminants from their source areas to the lake, and this report attempts to describe the monitoring efforts that have sought to characterize the quality of surface water in the Coastal Nonpoint Pollution Control Plan Area (CNPCPA). For this project, all water-quality data available from several sources were assembled into a database, and analyzed for trends using multiple regression analysis. Of the 1,079 water-quality attributes that were analyzed for trend, 536 (50%) exhibited a statistically significant time trend. Of those, 278 (52%) were positive trends (declining water quality) and 258 (48%) were negative trends (improving water quality). Additional supporting data files (Access database tables) are available for this open-file study.
You may also like:
Can't find what you're looking for? Feel free to contact us directly:
Indiana Geological and Water Survey
1001 E. 10th St.
Bloomington, IN 47405
IGS Return Policy
- Original sales receipt required.
- Returns accepted within 30 days of purchase date.
- Refund will be issued by the same method of payment as purchased.
- Products must be returned in the same new condition as purchased.
- Refunds on custom orders and digital products are NOT allowed.
- Customers are responsible for paying shipping costs to return products.