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The water resources of Dickinson County, Iowa and Jackson County, Minnesota provide an important source of recreation, drinking water, and aesthetic enjoyment for 17,000 residents and one million visitors each year. Good water quality is vital to the region’s economy and enhances the quality of life for those who visit or reside in the area.

Water Quality

Watershed –  Rainfall along with underwater springs feed the watershed of the Iowa Great Lakes. The Big and Little Spirit Lake watershed includes a large area in Jackson County along with areas in Iowa located East and West of Little and Big Spirit Lake. When Spirit Lake reaches its crest level, excess water from Spirit Lake moves down a spillway into East Okoboji. This spillway is located at the South end of Spirit Lake in the Town of Orleans.


Lake East Okoboji, West Okoboji, Upper Gar, Lower Gar, and Lake Minnewashta are at the same level. The level of these five lakes is controlled by the level of water at the dam at the southern end of Lower Gar Lake near Milford. Water flowing over the dam begins Mill Creek that joins the Little Sioux River South of Milford. The Little Sioux River eventually empties into the Missouri River.

IGL Watershed Map.JPG

The map on the left shows the four major watersheds of the Iowa Great Lakes.   Lakes are shown in dark blue.

The primary threats to the region’s water quality are from agricultural nutrients, soil erosion, human and livestock waste, storm water contaminants, urban development and loss of natural wetlands. Other threats include potential spills of hazardous materials and invasion of aquatic nuisance species.

What is Low Impact Development?

Low Impact Development (LID) is an innovative storm water management approach with a basic principle that is modeled after nature: manage rainfall at the source using uniformly distributed decentralized micro-scale controls. LID's goal is to mimic a site's predevelopment hydrology by using design techniques that infiltrate, filter, store, evaporate, and detain runoff close to its source.


Instead of managing storm water in large, costly end-of-pipe facilities located at the bottom of drainage areas; LID addresses storm water through small, cost-effective landscape features located at the lot level. Many landscape features like parking lots, streets, medians, sidewalks rooftops, and open spaces can be used to slow the flow of water and minimize the amount of water that flows directly into a lake.

For more information on Low Impact Development check this website:  LID Website


Dickinson County Clean Water Alliance

Founded in the late 1980’s, the mission of the Dickinson County Clean Water Alliance is to coordinate and communicate for the improvement and protection of the water resources affecting Dickinson County. The CWA is a coalition of over 60 government agencies and non-profit organizations that work together to coordinate water quality planning and protection. For more information on water quality see the Clean Water Alliance website:



The goal of the Cooperative Lakes Area Monitoring Project is to address the need for a long-term, unified approach to monitoring Dickinson County lakes. CLAMP depends upon volunteers to donate their time and energy. Volunteers attend a two-hour training session at the beginning of the summer and commit to sampling 2 - 3 times per summer. For more information about CLAMP or to volunteer contact Jane Shuttleworth at 337-3669 ext 7 or email -  



Dickinson County Water Quality Commission

Is a Dickinson County inter-agency commission including cities and the county set up under a 28E agreement to provide funding for water quality improvement projects. Contact is made through the Clean Water Alliance.

Dickinson County

Conservation Board

Iowa Lakeside


Iowa Lakeside Laboratory is a field station of Iowa’s Regent universities.  It provides summer classes and research opportunities for college students and educational programs for the Iowa Great Lakes community. Through a partnership with the State Hygienic Lab at the University of Iowa, Lakeside operates a year-round water-testing lab that serves public and private clients. For more information about water testing, contact Dennis Heimdal, water chemist, at 337-3669 ext. 6 or e-mail  For information about Lakeside Lab, visit

The Conservation Board is a Dickinson County agency responsible for county parks and bike trails. Their office is at the Nature Center - 2279 170th Street, Okoboji, IA 51355.

Telephone: 336-6352

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