The structures included under track culvert crossings, over bridges, under bridges, viaducts and retaining walls. The culverts varied in size and length, up to 2 m in diameter and 30m in length. The bridges were constructed in a number of forms; masonry arch, cast iron trusses, steel beams and either carried the railway over road or glens or carried the roadway over the rail. Retaining walls varied in size, up to 10m high and 600m long. As well as requiring work at height, in confined spaces and adjacent to operational railways many of the structures were in remote locations and were difficult to access via conventional equipment.

Inspections were recorded electronically on a BMX asset management system, as well as written reports. A summary spreadsheet of all structures was produced by BSA which prioritised repairs necessary with indicative budgets, and future monitoring regimes.