New York State inspectors assess all bridges in the state every two years including a bridge’s individual parts. Bridges are analyzed for their capacity to carry vehicular loads. Inspectors are required to evaluate, assign a condition score, and document the condition of up to 47 structural elements, including rating 25 components of each span of a bridge, in addition to general components common to all bridges. The NYSDOT condition rating scale ranges from 1 to 7, with 7 being in new condition and a rating of 5 or greater considered as good conditionBridges that cannot safely carry heavy vehicles, such as some tractor trailers, are posted with weight limits. Based upon inspection and load capacity analysis, any bridge deemed unsafe gets closed.

These are just the bridges in Tompkins county (home of Cornell University and Data Description).

How does the condition of a bridge relate to its age at inspection? Are there outliers and, if so, can you account for them by identifying them?