As far as historical scour data, I do not know that such data exists, but it may.
The best I can suggest is an analysis of the current conditions, then a narrative prediction/conclusion of what scour may have occurred and is likely to occur at that structure.
HEC-RAS has free software at the USACOE website. The HEC-RAS method is universally accepted throughout the USA, to my knowledge.
This software has a scour analyis option, which should be fairly straightforward to anyone with hydraulics educational background; but I would imagine it is almost unusable to someone without hydraulics educational background.