One problem with the way this is framed: Rivers have historically meandered. They didn't have a set path. The modern expectation that rivers have a set path is

One problem with the way this is framed: Rivers have historically meandered. They didn't have a set path. The modern expectation that rivers have a set path is one we tend to try to actively enforce. Elsewhere in comments here, someone noted that the Salton Sea is similar. But if you read Salt Dreams, Native Americans had oral history suggesting that there had been a lake there previously. Geological records agree with the oral history.