On the old frontage road there is a bridge which spans the river and is I guess about 150 to 180 feet above it. This first picture shows the freeway (I-90) as is crosses the gorge and gives some perspective to the width of the river and length of the stride for the footprints.
The images shown on this site have only been re-sized or cropped to fit the web page. The camera I used is a 38mm Kodak with a 10x view. This first picture is zoomed in perhaps 3x (115mm). After taking these pictures, I uploaded them to my computer and forgot about them until the first part of April; therefore I can only guess at the zoom in rates.
Notice in the bottom almost center of the picture the crossed footprints on the ice.
The second picture is zoomed in to 380mm (10 power). Notice the gait, especially of the upper tracks. Also notice the size of the footprints. 
These most likely have become larger with the melting of the snow (I have no idea how many days before I took the pictures that these were made). As snow melts, footprints will become larger.
However, the distance between each foot step (or gait) will not get bigger, if anything the distance will get smaller as the footprint gets larger. The gait should be measured from the center of each print to the center of the next print.
Using the first photo, I would estimate that the distance from shore to shore where the footprints are (at a diagonal line in the photo) to be about 200 to 300 feet wide. My guess is that the gait would be between 3 and 4 feet wide, probably closer to 4 feet. If it was made by someone with snow shoes, that is a very good stride (next to impossible) and if it were made by a human it again would be a very large stride. Notice the tracks by the crack in the ice.
From the crack to where they meet to form the X, the left foot touched the ice 4 times and gets lost in the mixup on the 5th step.
After the footprints cross, notice that the furthest set continues that long stride. It appears to me that there is either 2 creatures going the same way, or one going across and comming back.
The third picture is another view. I got off the bridge and walked about 40 feet downstream. My elevation with the bridge would have dropped at the most 20 feet so I would estimate that I am still a good 150 feet or more away from the river.
The last picture is a zoom in on the footprints. It looks like toes are spread out on them, especially by the crack in the ice.
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Remember, these pictures are taken about 150 - 180 feet away from the top of a bridge.