The Snow Bridge

This assignment is to work in teams of 4 or 5 to build a bridge of snow.
The bridge must have a span of 3 feet and a height under the bridge of 3 feet.
The bridge can only be composed of snow and water, no additional materials are allowed.
The bridge must be able to support 100 lbs.
The bridge must have a theme and visual appeal.
The bridge will not be spanning a stream or other natural feature.
Each team must put together a proposal that they will make to the class.