Animas River Changes in the Valley

I was recently looking back at some of the imagery of the Durango Area on [www.historicaerials.com] and noticed there were two major instances of Animas River bed circling west underneath the Silverton Branch right of way south of Hermosa. This site only has aerials going back to the 1960s but at that point in time it looked like these two parts of the river had dried up and moved further east of the right of way, suggesting there were possibly bridges here that later became fills.


compared to [www.google.com]

Would anyone with access to possibly the 1919 ICC valuation maps or any other sources be able to confirm if there were bridges/boxes/fills in these areas? What MP would these be at?