Appalachian History Series
A Lake for Floods and for Folks
Where Johns Creek bends through the hills above Prestonsburg, the U.S. Army Corps of Engineers raised an earth dam in the mid twentieth century and impounded an 1,100 acre reservoir that locals still call Dewey Lake. Authorized in the Flood Control Act of 1938, the project was conceived after the Ohio Valley’s devastating 1937 flood to cut peaks on the Big Sandy system and to create public lands for wildlife and recreation. The story that follows draws on Corps plans, technical studies, and contemporaneous newspapers, alongside the site history you shared.
From 1937 Floods to Federal Green Light
A winter of ruin set the stage. The January 1937 freshet put towns from Catlettsburg to Cincinnati under water and pushed Congress to expand a basin wide program of reservoirs. Lawmakers responded with Public Law 75-761, the Flood Control Act of 1938, which authorized a slate of Ohio River works and set policy for federal flood control in partnership with the Corps. Dewey Dam on Johns Creek entered planning within that framework, listed among Big Sandy tributary controls.
As the Corps surveyed Johns Creek in the late 1930s, engineers picked a narrow bedrock gorge as the best foundation for a rolled earth embankment with a concrete outlet tunnel and an overflow spillway. Those design choices and the reservoir’s operating plan are preserved in the project’s Water Control Manual, the governing document for flood storage and releases.
Breaking Ground After the War
World War II delayed construction across the Ohio basin, but Dewey moved from paper to dirt in the spring of 1946 when contractors mobilized to drive the outlet tunnel and pour the stilling basin before placing the main fill. The Corps’ manual and technical archives document the sequence and the model testing of the spillway later performed at the Waterways Experiment Station. Impoundment began in 1950 and the dam reached completion by 1951.
What the Lake Took and What It Gave
No incorporated town vanished beneath Dewey, but the taking was real. The federal government acquired thousands of acres in fee and flowage to hold the flood pool. Families on scattered bottomlands sold homesteads and farms, roads were rerouted, utility lines moved, and dozens of small cemeteries were reinterred on higher ground. Post impoundment, most rim tracts reforested under public management, and large swaths were set aside for fish and game work. These tradeoffs, recorded in the project history and echoed in local memory, marked a common Appalachian pattern in the reservoir era.
A Park With a New Name
Recreation quickly took root. On January 1, 1954, Kentucky opened Dewey Lake State Park, soon renamed to honor pioneer survivor Jenny Wiley. The park and lake became a regional draw for camping, boating, and the lakeside amphitheater, a civic investment layered atop a federal flood work. Contemporary and later state and local histories preserve the timeline of the opening and renaming.
How Dewey Works When the Rains Come
Dewey is one of several Big Sandy reservoirs that operate in concert. During heavy runoff, operators store Johns Creek inflow to cut downstream crests, then release water as the main stem’s stage allows. The Corps’ manual explains that rule curve, storage allocations, and coordination with the Ohio River schedule. Local papers in the 1950s tracked how much the lake rose in specific storms, illustrating the system in action for readers in Prestonsburg and along the Levisa Fork.
Science on the Water
Biologists and hydrologists quickly turned Dewey into a field laboratory. A U.S. Geological Survey investigation in the 1970s examined sedimentation dynamics in Dewey and nearby Fishtrap Lake, documenting Johns Creek’s geology, reservoir trap efficiency, and shoreline change. Kentucky fishery bulletins traced how sport fish communities developed under active management. These primary studies show how a flood project also became a long running science site.
The Legacy in the Hollows
Dewey Dam is a New Deal era promise built late. It brought a measure of safety to flood prone valley towns and seeded a park economy on former farms. It also relocated families, rerouted roads, and moved graveyards. The record in plans, reports, and newspapers keeps both sides of that ledger. For Appalachian historians, the lake on Johns Creek is a clear case study in how federal flood control re made mountain valleys in the twentieth century.
Sources & Further Reading
U.S. Army Corps of Engineers. Dewey Lake Water Control Manual (latest redacted public version). Policies, operating diagrams, project history, and design notes. Water Data
U.S. Congress. Flood Control Act of 1938, Pub. L. 75-761, 52 Stat. 1215. Authorizes Ohio River basin flood works. GovInfo+1
U.S. Army Corps of Engineers, Waterways Experiment Station. Model Study of Spillway for Dewey Dam, Johns Creek, Kentucky. Technical report. usace.contentdm.oclc.org
U.S. Geological Survey. Boggs, S. Jr., et al. Fluvial Sediment Study of Fishtrap and Dewey Lakes, Kentucky (1977). U.S. Geological Survey
Kentucky Department of Fish and Wildlife Resources. The Dewey Lake Fishery During the First Twenty Years (Fish Bulletin 47). Kentucky Department of Fish & Wildlife
Floyd County Times coverage and community retrospectives on Dewey Lake, park naming, and flood operations in the 1950s. kykinfolk.org+1
City of Prestonsburg. “Who Was Jenny Wiley.” Local park history summary. Prestonsburg Tourism
Kentucky State Parks. Jenny Wiley State Resort Park overview and amenities. Kentucky State Parks