Human remains that could be 7,000 years old have been found by sewer construction workers on the southeast side of Des Moines.
The remains were discovered in January.
They were found near a site where scientists think people harvested, cooked and ate clams thousands of years ago.
State archaeologist John Doershuk (DOHR'-shuhk) told The Des Moines Register that it's "a rather unique site, not only in Iowa but in the Midwest."
The site's exact location is not being disclosed, lest looters ravage it.
The discovery and archaeological dig is delaying a $37.8 million sewer project for at least six months. It's estimated the Wastewater Reclamation Authority will have to spend an estimated $1.5 million or more because of the delay.