The book Westward documents this, as well as he reason for not using the bridge:
The first of these bridges, built by a French frontiersman, Reshaw, spanned the river just east of the site of Casper. It was there in 1857  when the belated Mormon handcart companies trailed by. Members of those companies have told the writer that they would have used this bridge, but they could not pay the high tolls. As an alternative they had to pull their cars through the cold stream, which nearly swept some of the women and children down with it. That same afternoon a bitter wind froze their water-soaked clothing and bedding; and a snowfall at night took a heavy toll of lives. This was the beginning of one of the major tragedies of the plains. (Driggs, Howard, P. 87)
Isaac Wardle indicated that the handcart troubles started at this river crossing.
Isaac indicated that the serious problems for the company started after the last crossing of the Platte River:
…We encountered a sever[e] snow storm at Platt[e] Bridge this was early in October. Then our old men and women and some of the younger children began to give out and to get sick and many of them died which I helped bury, but we kept moving on a little every day in spite of the cold and hardships. At one time I became so weary and over come with cold that I fell down and was forced to lay there for some time. About this time one day while we were stopped for noon two men rode into our camp, they were "Joseph Young" and Ephraim Hanks who had come to tell us that men where coming to meet us with teams and wagons from Salt Lake City. (Church History, Wardle)
|Two who forded the Platt|