Source: https://erdc-library.erdc.dren.mil/jspui/ The navigation locks at the proposed Olmsted project, Ohio River, will consist of two 110- by 1,200-ft locks having a design lift of 21 ft. The locks' filling and emptying system consists of culverts from the land wall, the river wall, and the middle wall emptying into a single outlet structure located in the river. The Olmsted Lock design is unique in that the four culverts from the two locks all terminate in a common outlet structure. Tests were conducted on a 1:25-scale model of the proposed Olmsted Lock outlet structure that reproduced 1,150 ft of the Ohio River beginning 650 ft upstream of the outlet and approximately 400 ft of the width of the river. This model was used to evaluate the performance of the outlet structure for the project. Observations of flow patterns in the vicinity of the outlet structure during emptying operations indicated that no adverse flow conditions resulted from the combining of the four culverts into one outlet structure. Stability tests were conducted with the type 1 design riprap plan, which consisted of stones having a D50 of 20 in. placed from sta 30+46 to sta 35+66 and from the lock wall riverward 250 ft. With a river unit discharge of 130 cfs/ft and a tailwater elevation of 279 and with both locks discharging 10,500 cfs per lock for 5 hr (prototype), a few stones were displaced in an area about 15 to 25 ft riverward from the outlet structure. The type 2 design riprap plan (stones having a D50 of 24 in.) was found to be stable for these flow conditions and is recommended for the prototype.