https://apnews.com/article/bridge-safety-ntsb-pittsburgh-collapse-c48540ffa35a062a0dfe246d1d240b6d > Investigators looking into the collapse of a Pittsburgh bridge want transportation officials nationwide to examine more than 10,000 other bridges with similar construction to ensure they don't have the same kind of corrosion that was found on the bridge that collapsed. > The National Transportation Safety Board said in a report Thursday that drainage problems on the weathered steel bridge that failed allowed the metal legs to deteriorate over time. It determined Pennsylvania neglected for years to perform the maintenance needed to clear the debris, dirt and leaves that was causing the problem even though inspectors noted the issue.