SPRINGFIELD -- Low water levels on the Sangamon River have exposed some of Sangamon County's pioneer past.
Foundation blocks and possibly some of the inner workings of what was once Carpenter's Mill have been revealed at Riverside Park, just west of the Business Route 55 Bridge.
The mill operated between 1830 and 1870. Pictures from the Sangamon Valley Collection of the Lincoln Library show a three-story structure sitting on an elevated foundation above the Sangamon River.
Discovery of the remains opens a window into mid-1800s Sangamon County history - and also poses a challenge to the Springfield Park District as it considers how best to protect the site.
The location has been an attractive spot for fishing for more than a century. Old pictures show people fishing in the riffle between the mill and Carpenter Park.
Its popularity is one reason protection is difficult.
Signs that ask people to keep to the main road have been ignored, and dirt roads have been cut through the bottomland forest from Riverside Park to the bridge where the mill site is.
Foundation stones have been moved and fires lit inside the remains of the mill drive mechanism -- now mostly buried in sand.
Park district executive director Michael Stratton met last week with archaeologist Floyd Mansberger of Fever River Research to view the mill and discuss the potential for its preservation.
Once the mill was brought to the park district's attention, metal posts were driven into the ground to block the makeshift roads, but people have been going around the posts or simply pulling them out and driving in anyway.
"How do you protect something like this?" Mansberger asked. "I'm not sure I have the answer."
Also, the site is often underwater, exposed only during periods of low water.
For now, park visitors are asked to observe signs and not start fires, especially in the "tub," which is constructed of wooden staves that could be burnt.
Despite the difficulties, Mansberger said the site is significant.
"None of this stuff is written down," he said. "The structure of the mill, the floor plan and the mechanical workings of it all give us information about that pioneer period of the 1830s, '40s and '50s."
Of special interest is the "tub drive," a relatively advanced technology for the time that powered the mill by water falling into a tub with a turbine at the bottom. This design was an advance in efficiency over the more familiar water wheel, Mansberger said.
Whether the turbine is down there or not is another question," he said. "Is it there? There's a good chance."
Mansberger said he's never seen a tub-drive mechanism in his 35-year career.
Unearthing this one would be an exciting find.
"That's pretty cool," he said. "Period."
Stratton said he wants to meet with Mansberger again and also will contact the Illinois Historic Preservation Agency.
"We are going to see what level of protection we need and what process we need to go through."
He said the park district has experience with historic properties, notably Washington Park, which was designed by Ossian Simonds and listed on the National Register of Historic Places.
He also wants to see if the public has more information on that stretch of the Sangamon River, including the old Route 66 Bridge.
"When we asked the public to bring forth pictures (of Lincoln Park for its centennial celebration), people went through their closets, their parents' closets and their grandparents' closets," he said.
Mansberger said the mill deserves to be preserved.
"It is a public resource. It belongs to all of us, and it should be protected," he said.