Lincoln State Park Dam Repair

The dam is classified as a high hazard dam, and that classification means it is subject to inspections from the DNR Division of Water.

Those inspections have revealed water seeping through the dam at the toe, voids under the concrete spillway, and trees on the dam, the roots of which may create voids for additional water to seep through the dam. The project will also address the aging control structure that is used to lower the lake.

Because the repairs will affect the park road below the dam that leads to the nature center and the Pine Hills Group Camp and group cottages, those facilities will be closed during repairs. The beach will be operational through the Independence Day weekend but will close on July 7 as preparation for repairs begins.

Boating on Lake Lincoln may occur until July 7. Please note that boat rentals will not be offered during the 2025 season, so you must bring your own kayak or canoe. Boats with electric motors are permitted on the lake. DNR Lake Permits can be purchased at the Lincoln State Park office or ShopINStateParks.com.

The main impact will be access to Sarah Lincoln’s Woods Nature Preserve. The Nature Preserve Trail (Trail 3) can be accessed from the Lake Trail (Trail 1), which will make it a roughly 4.7-mile roundtrip to hike through the preserve. The portion of Trail 1 that crosses the dam will be closed during construction.

Water leaching through the dam could cause it to fail, resulting in flooding in the park, neighboring agriculture fields, homes, and parts of the town of Gentryville.

All trees will be removed from the dam to prevent root damage to the dam structure. A toe drain will be installed, and a stability berm will be built for the dam. Low spots will be raised to keep the level of the top of the dam consistent. A new siphon system will be installed to regulate the lake level, and the old control structure will be removed. Voids under the spillway will be filled with polyurethane grout, and all joints and cracks will be cleaned out and new mastic (sealant) installed. All utilities currently buried in the dam will be relocated.

Timing is very important in this project, and late summer through fall are the driest  seasons to work. The lake must be lowered a month before work begins so that there is time for the area to dry. After repairs are completed, there must also be time to seed the dam to prevent erosion during the winter and following spring.

The Division of State Parks is working closely with the Division of Engineering to complete this project. Commonwealth Engineering completed the studies and prepared the design. Omni Earthworks is the general contractor for the repairs.

This project is funded through a deferred maintenance allocation from the Indiana General Assembly.

The Division of State Parks works closely with the Division of Fish and Wildlife on fisheries in all of our lakes. We have seen a significant increase in the number of gizzard shad in Lake Lincoln during the last 5 years. Gizzard shad compete with bluegill and small bass for food. In lakes with gizzard shad populations, bluegill growth is stunted, and the bass numbers decline. This project to restore the lake allows us to address the gizzard shad population and should result in the removal of that species.

Before the project begins, DNR fisheries biologists will remove some healthy fish from Lake Lincoln and release them at Weber Lake inside the park. Weber Lake, once an acidic strip mine pit that could not sustain fish or other wildlife, was restored during the early 2000s through the Division of Reclamation’s Abandoned Mine Lands program and is now a healthy aquatic feature in the park. After Lake Lincoln refills, fish from Weber Lake will be brought back to Lake Lincoln to jumpstart the fishery. Lake Lincoln will also be restocked with 3- to 4-inch largemouth bass, and 2- to 3-inch bluegill and redear sunfish in fall 2026. Channel catfish will be added in 2027.

We encourage anglers who fish at Lake Lincoln to catch and keep their daily limit of bass, bluegill, and other native fish during the spring and early summer of 2025. When the lake is closed and water levels begin to drop, the remaining fish in the lake will die as oxygen levels decrease and they are concentrated in small pools.

There will likely be some odor as the fish decay, but there may also be an increase in the ability to watch wildlife as raccoons, birds and other fish-eating species enjoy some extra food.

Please do NOT plan to bring fish to the lake. Transporting fish into public waters is illegal. Although Lake Lincoln has historically had healthy underwater habitats for fish, and we expect that to return, there may be opportunities to assist with construction of fish structures as part of this project. More information will be made available as the work progresses.

Wildlife like beavers and turtles will be affected; however, they can move to other locations to find suitable habitat. Weber Lake is available on the property, and species may move upstream or downstream as well.

Interpretive programming will continue at the beach or shelters and at the Jones Home in Gentryville. Guests can find schedules of upcoming interpretive programs at on.IN.gov/lincolnsp.

The original moon tree, a sycamore planted by the Girl Scouts in 1976 that grew from a seed carried to the moon on Apollo 14, was removed because of the upcoming dam repairs. Thanks to the foresight of DNR staff, branches from the original moon tree were grafted and grown by the Division of Forestry and have now been planted at Lincoln State Park. One tree is below the dam and across the road near the old nature center. The original monuments are near this tree, which will be inaccessible during the repair project. The time capsule associated with the monuments will be moved and opened in 2026 as scheduled. The other three trees are planted in the Troy Road picnic area close to the playground and can be viewed as they grow.

The project is estimated to be complete by the end of 2025. The nature center will reopen in early 2026. Pine Hills Group Camp reservations can be made a year in advance. Group cottages will open for reservations in November 2025 for use in 2026. Planned opening of the beach and boat rental is Memorial Day weekend 2026, but that will depend on the amount of rain received to refill the lake.