Why fossil studying is so great at Caesar Creek Lake:
In the process of building the dam at Caesar Creek Lake, the U.S. Army Corps of Engineers created an emergency spillway to act as an overflow for the lake. The spillway crest is lower than the top of the dam, preventing water from overtopping the dam. Instead, the water will flow around the dam into the creek downstream of the dam should the lake ever reach its flood storage capacity.
When the U.S. Army Corps of Engineers blasted earth and rock to form the emergency spillway, bedrock bearing fossils of ancient sea creatures were exposed. The exposed layer of limestone/shale bedrock is approximately 438 million years old. At that time, what is now Ohio lay under a warm, shallow sea. Over time, sediments covered the creatures. Pressure from layer upon layer of sediment eventually turned the animal remains into rock.
Today, these remains are lying on the surface. The vast majority of the fossils are brachiopods, which look like sea shells, and bryozoa, which look like coral. You may also find tiny discs that look like a stack of life savers called crinoids or snail shells called gastropods. The most difficult fossils to find are horn coral, cephalopods, and Ohio’s state fossil: the trilobite.
Fossils may be observed in the spillway at any time, but the collection of fossils is prohibited without permission from the Corps of Engineers. If you would like to collect fossils, you must first acquire a free fossil collecting permit from:
U.S. Army Corps of Engineers Visitor Center
4020 N. Clarksville Road
Waynesville, OH 45068
Please observe the following rules:
- Fossils may not be collected for commercial use.
- No tools are allowed in the spillway. No breaking of rocks or hitting of one rock against another.
- You may keep fossils (or rocks containing fossils) that fit in the palm of your hand. Larger specimens should be left for others to enjoy. You may photograph, draw, or take rubbings of larger specimens.
- Fossils may only be collected in the emergency spillway. Collecting in any area other than the spillway is not permitted.
For your safety and convenience:
- You may park in either of the two parking areas in the emergency spillway. Parking on the shoulder of the road is prohibited.
- Climbing the walls is very dangerous. The walls are very unstable, and we ask that you remain on the spillway floor. DO NOT CLIMB THE WALLS OR THE DEBRIS BELOW THE WALLS and STAY IN FRONT OF THE “NO CLIMBING” SIGNS!
- Bring drinking water with you. The spillway has no shade.
- 24-hour restrooms are located at the Visitor Center. There are no restrooms at the spillway.