I saw a similar sight to this picture in Nebraska, and wondered why anyone would do this. (Art project maybe?) I Googled this image and came across an article explaining that these cars were put here in the 50’s for erosion control:
Throughout Montana, the U.S and beyond, there are rusted cars scattered along the banks and bottoms of rivers that are remnants of a time when rivers were less regulated and self-reliant people were trying to figure out how to battle the escalating problem of erosion. These cars abandoned by their owners are relics from a 1950s erosion control experiment, when cars were taken from wrecking yards and dumped into the river, hopefully, to stabilize the eroding bank. The cars would have their engines and other innards removed by cutting torches and hauled down the streets to their destination. Once in the water, if the cars held, they became a sturdy part of the bank, resisting the river’s strength in ways soil couldn’t. Some cars didn’t hold and would drift down the river becoming an odd sight.
Click on the link to see even more pictures of old rusted cars in river banks,