The transition from raw western wilderness to “civilization” began with the displacement and genocide of indigenous peoples, followed by wagon trains, and then by railroads. Here the balance of power between humans and Nature is seen in context: a railroad track built on construction fill built just above a river that, in flood, could easily (and probably did) temporarily destroy the human accomplishment. The turbidity of the river in this place, and at this stage, is likely due to soil erosion in the watershed (catchment) caused by grazing and farming.