The Iowa Department of Natural Resources maintains jurisdiction for Iowa's lakes including the lake bottom. The DNR shoreline jurisdiction extends from the waters surface to the Ordinary High Water Line (OHWL). For the chain of five lakes (East Okoboji, West Okoboji, Upper Gar, Lower Gar, and Minnewashta) the Ordinary High Water Line is defined as 30 vertical inches above crest level at the dam at the lower end of Lower Gar Lake or 1397.768 feet above Mean Sea Level (MSL). For Spirit Lake and the rest of the lakes in Dickinson County the DNR has a 12 vertical inch jurisdiction.
The Iowa Department of Natural Resources contacts for shoreline erosion is Biologist Michael Hawkins located at the Spirit Lake Fish Hatchery - telephone 336-1840 or Conservation Officer Blake Mills at cell phone 712/ 260-1017.
Shoreline above the point of DNR jurisdiction is generally covered by shoreline ordinances and zoning of the appropriate municipal government or - if the shore is not in any municipality - Dickinson County Zoning Administrator (Mr. David Kohlhaase) at the Dickinson County Courthouse, Spirit Lake, telephone 336-2770.