A new report released by the American Road and Transportation Builders Association (ARTBA) has revealed that 54,259 bridges across the US are rated ‘structurally deficient’.

The analysis is based on the US Department of Transportation’s 2017 National Bridge Inventory database.

The data shows that cars, trucks and school buses cross these bridges nearly 175 million times per day.

ARTBA chief economist Dr Alison Premo Black said that it would take 37 years to renovate all these structures at current pace of repair and replacement.

In the last year, the rate of improving the nation’s inventory of structurally deficient bridges also decelerated, dropping by two-tenths of a percentage from its 2016 government data.

“The data shows that cars, trucks and school buses cross these bridges nearly 175 million times per day.”

All bridges, decks and associated structures are regularly inspected to review their condition and then rated on a scale of one to nine, where a higher rating indicates better condition.

Bridges with a rating of four and below are categorised as structurally deficient signifying that the structures need attention.

ARBTA analysis found that Iowa has the maximum number of structurally deficient bridges followed by Oklahoma, Missouri and Illinois.

The District of Columbia has the least number of bridges classified as structurally deficient succeeded by Nevada, Delaware and Hawaii.

The analysis also revealed that at least 15% of the bridges in six states, namely Rhode Island (23%), Iowa (21%), South Dakota (19%), West Virginia (19%), Pennsylvania (18%) and Nebraska (15%) fall in this category.