(KCCR) — Access to the Oahe Dam on the Stanley County side of the Missouri River will be shut off due to an upcoming road construction project for most of the month of September. The South Dakota Department of Transportation says State Highway 1806 will be closing Tuesday September 8th, just north of the Game, Fish and Parks Office so mainline cross pipes can be replaced. The location is west of Pierre/Fort Pierre and approximately two and a half miles north of the Highway 14 junction with Highway 1806. The project contractor, Steve Lehrkamp Enterprises of Herreid, will set up traffic control to close the road at that time. Work will begin shortly after traffic is shut down. Through traffic will need to find an alternate route through the work area. The work should take two to three weeks to complete. The overall completion date is October 30th. The cost of the project is 798-thousand 800-dollars.