Complex sentence: As Cow Creek flows down its valley bottom, it meanders from one precipitous sidewall to the other; while traveling up Cow Creek freight wagons crossed Cow Creek 31 times.
Split into simpler sentences: As Cow Creek flows down its valley bottom, it meanders from one precipitous sidewall to the other. Thus, while traveling up Cow Creek through the breaks the wagons using the route crossed Cow Creek 31 times.