Repairs at Copan Dam detours SH-10 traffic

A repair project started last week at Copan Dam which will cause much of the eastbound traffic on State Highway 10 to be re-routed onto U.S. 60 — probably until early next year.

The project involves rehabilitation of the U.S. Army Corps of Engineer-operated dam’s tainter gates, which are radial-arm floodgates that help the 30-year-old structure regulate water flow.

Corps officials said the tainter gate repairs were “scheduled maintenance,” noting that the project “is not related to recent weather events.” A few days before the announcement, heavy rains washed two Osage County roads near Bowring, approximately five miles north and west of Copan.

The work is expected to continue through the end of the calendar year, Corps officials said. Replacement of wire ropes on the dam is another part of the repair project, which is to be carried out by Arkansas-based McCormick Industrial Abatement Services. Other work is planned to repair damage to highway’s shoulder areas along the dam crossing, officials added. Highway 10 traffic over the dam had recently been reduced to one lane.

SH 10 was finally closed down Wednesday, June 1, north the dam — which is in northwestern Washington County approximately 22 miles east of Highway 10’s longtime western terminus at its junction with Oklahoma 99 in Osage County, 10 miles northeast of Pawhuska.

Last weekend, a lighted sign was put into operation on U.S. 60, approximately a quarter mile southwest of the SH 99 junction. The flashing sign informs northbound motorists that Oklahoma 10 traffic to Copan will be re-routed east on Highway 60 to northbound U.S. 75 in Bartlesville.

Construction of the earthen dam at Copan started in 1972 and the flood-control project was completed April 1, 1983. Rising to a height of 73 feet and with a length (at its crest) of 7,730 feet, the dam impounds about 4,850 acres of water from the Little Caney River. The reservoir the dam creates has a water surface of 7.6 square miles.

Copan Lake is part of a comprehensive plan for flood control and water conservation in the Caney River and Bird Creek Basins. It is operated in conjunction with other lakes in the Verdigris and Arkansas systems. Copan’s reservoir provides flood protection for about 3,500 acres immediately below the dam and an additional 49,000 acres throughout the Caney River Valley downstream to Bartlesville.

Just five miles west of Copan Lake, in Osage County, is Hulah Lake — on which construction started in 1946 and was completed in 1950. Hulah impounds the Caney River. Corps officials said Hulah Dam currently has no repair needs.

Oklahoma 10’s undetoured previous length of 235 miles made it the state’s sixth-longest highway. On its bizarre crescent-shaped course, SH 10 runs east-west for its first 100 miles. A few miles past Miami, it then runs north-south for the remainder of its course before reaching its southeastern terminus when it meets Interstate 40 near Gore. Along its way, Highway 10 travels through 10 counties — Osage, Washington, Nowata, Craig, Ottawa, Delaware, Adair, Cherokee, Muskogee and Sequoyah.