The Michigan Office of the Auditor General released its overdue performance audit of MDoT’s Bridge Inspection Program Friday afternoon, just in time to miss last week’s news cycle. Weekend news reports focused on bridge inspection frequency, but there is a more fundamental question which should be answered first: Are the MDoT bridge records which were audited complete and correct? Even remotely so?
The Federal Highway Administration collects bridge data from the State DoT’s and other sources to create and maintain the National Bridge Inventory. It is supposed to list all American bridges which have roads running across them or below them, along with ownership, identifiers, and condition data. Condition data is given as a number from 0 (failed) through 9 (good beyond current standards). These numbers then get converted into the descriptors you read in the press, such as ‘structurally deficient’, poor, good, etc.
The MOAG performance audit is replete with statistics derived from MDoT’s bridge inventory database which show – no surprise – that some of Michigan’s bridges are in poor shape. You can see MOAG’s statistics as of April 30th, 2014 in the audit or go to a searchable database of individual bridge data across the entire country, as of 2012, brought to us by Alexander Svirsky of MassRoads.com.
A first pass at the MOAG bridge inspection audit involved looking at the worst condition category of bridges, those rated 0 or 1 for failed or imminent failure. Going through the Wayne County owned bridge summary on Page 51 of the new MOAG audit, I was heartened to see that Wayne County has no condition category 0 or 1 bridges. But there are at least two zero condition category major bridges in Wayne County across the Rouge River, so let’s say I am experiencing a little cognitive dissonance just now.