A popular visitors spot on the shore of of Lake Michigan, Indiana Dunes National Lakeshore is closed for the summer as scientists investigate what is causing holes to appear in the sand dunes.
Officials at Indiana Dunes National Lakeshore announced Thursday that scientists still do not know what caused holes to appear in Mount Baldy last summer, and the popular attraction will remain closed for further study.
Ground penetrating radar studies performed by the Environmental Protection Agency have identified a large number of anomalies below the dune’s surface, but scientists from the National Park Service, Indiana University and the Indiana Geological Survey still do not know how these holes were formed.
The two additional holes and a number of depressions have been found since July. Officials said the holes are short-lived, remaining open for less than 24 hours before collapsing and filling in naturally with surrounding sand.
Officials at the national lakeshore on Thursday announced more testing will be conducted this summer. That work will include mapping of openings and depressions, as well as scientific studies of the internal architecture of the dune.
One hole swallowed a child who had to be rescued. Nathan Woessner, 6, had sand collapse under him during a family visit there. This could have been REALLY tragic but he was rescues after more than three hours.
Trails exist over the dunes which allow people foot access. Not a good idea. In addition, the native grasses that hold the dunes in place are not widespread. The park service is replanting dune grasses.
The National Park Service has a page about the ongoing investigation here. They also plan to install signage to explain the problem. The current idea regarding the holes is that organic material and structures were buried. Now that these have decayed, sand falls into the open internal space. That then propagates to the surface.