The arches are segmental rather than the semi-circular shape usually used in Roman bridges. Of the 4 arches that still exist, the largest span is . This is between the third and fourth piers. The piers have cutwaters. These are pointed both upstream and downstream. These mean there is less scour around the piers. This is one of the main problems for the stability of stone bridges. The piers were built with holes in the stone. This was to help lessen pressure from the flow of water when the river was in flood.