State officials say extended construction of inspection booths at the Blue Water Bridge is causing traffic delays at the crossing that connects Port Huron with the Canadian province of Ontario.

The Times Herald reports that work on the six booths has delayed traffic by at least an hour at times. The work was supposed to be completed by June 30.

Michigan Department of Transportation Department senior project engineer Meghan Vohs says the contractor has informed officials that the work will be completed by Sept. 12. She says one of the issues has been steel and other material not meeting state specifications.

The $1.5 million project's goal is to boost efficiency and security at the crossing.