Geologic image in the Kentucky Geological Survey data repository.Image Name: Image Date: 9/1/2004 Category: photo_culture Source: Greb, Steve Format: jpg Size (MB): 0.67 Pixel Dimensions: 2048 x 1536 Description: River traffic influences land use in Jefferson County. Canals and locks were first built in 1830 to bypass the shallows created by bedrock geology at Falls of the Ohio. In the 1960�s, older dams were replaced with the McAlpine Locks and Dam. More than 50 million tons of commerce annually transit the locks. Photograph by Stephen Greb, Kentucky Geological Survey.