Hawthorne Bridge and Morrison Bridge will be closed on Friday, July 4, for the Waterfront Blues Festival fireworks display. (File Photo/Portland Tribune)

The Hawthorne Bridge and the Morrison Bridge will be closed to motor vehicles on Friday, July 4, for the Waterfront Blues Festival fireworks show.

Both bridges will be closed to cars and trucks from 6 p.m. to midnight. Drivers will need to use alternative routes. The bridges will remain open for bicyclists and pedestrians. These closures are not weather-dependent.

Multnomah County is closing the bridges during this time because crowds often fill the bridges, and cars stop to watch the fireworks, which can cause safety issues.

Starting at 7 p.m. on Thursday, July 3, the center westbound lane on the Hawthorne Bridge will be closed for crews to start setting up fencing equipment. It will remain closed until the bridge reopens Friday, July 4, at midnight.