Cold Water Spring State Preserve is a parcel state preserve protecting a spring that issues from Cold Water Cave, an extensive

cave A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

system in

Winneshiek County, Iowa Winneshiek County is a county located in the U.S. state of Iowa. As of the 2020 census, the population was 20,070. The county seat is Decorah. History A largely rural and agricultural county, Winneshiek County has a rich cultural history from ...

and

Fillmore County, Minnesota Fillmore County is a county in the U.S. state of Minnesota. As of the 2020 census, the population was 21,228. Its county seat is Preston. Fillmore County is included in the Rochester metropolitan area. History Fillmore County was created on ...

. The spring is a tributary of the

Upper Iowa River The Upper Iowa River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed May 13, 2011 tributary of the Mississippi River in the upper Midwest of the United States. Its headwaters rise ...

. The cave system contains a large underground creek that courses around much of the cave's nearly of passages. The cave system has some unusual features such as its rate of expansion, which is higher than that of most caves. It also has relatively low amounts of

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

and high amounts of

carbon dioxide Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...

. The cave is a

National Natural Landmark The National Natural Landmarks (NNL) Program recognizes and encourages the conservation of outstanding examples of the natural history of the United States. It is the only national natural areas program that identifies and recognizes the best ...

, designated in 1987.In 1987, the Cold Water Cave was designated as a National Natural Landmark by the National Park Service. There are two entries; both are on private property. Coldwater Creek Wildlife Management Area is a state hunting ground near Bluffton, and is near to the cave system. The cave is located in the

Driftless Area The Driftless Area, a topographical and cultural region in the American Midwest, comprises southwestern Wisconsin, southeastern Minnesota, northeastern Iowa, and the extreme northwestern corner of Illinois. Never covered by ice during the last ...

of Iowa and Minnesota, a region characterized by

karst topography Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...

, which involves disappearing streams,

blind valley A steephead valley, steephead or blind valley is a deep, narrow, flat bottomed valley with an abrupt ending. Such closed valleys may arise in limestone or karst landscapes, where a layer of permeable rock lies above an impermeable substract such ...

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

s, cold springs, and cold streams, all of which are present here.

Sources

Cold Water Spring State Preserve
Retrieved July 22, 2007

retrieved July 22, 2007
Interview with John Ackerman, July, 2003
retrieved July 22, 2007

References

External links

Exploring Iowa's Coldwater Cave
Documentary produced by

Iowa Public Television Iowa PBS, formerly Iowa Public Television (IPTV), is a network of Public Broadcasting Service (PBS) member stations in the U.S. state of Iowa. It is owned by the Iowa Public Broadcasting Board, an agency of the state education department which h ...

{{authority control Iowa state preserves Protected areas of Winneshiek County, Iowa Protected areas of Fillmore County, Minnesota Driftless Area Caves of Iowa Springs of the United States Caves of Minnesota Springs of Minnesota Limestone caves National Natural Landmarks in Iowa Protected areas established in 1987 1987 establishments in Minnesota Landforms of Winneshiek County, Iowa Bodies of water of Fillmore County, Minnesota