Heads up, Frederick Douglass Memorial Bridge users. The bridge is going to be closed Thursday morning for up to 2 hours to allow a water vessel to pass, according to DDOT officials. The swing span of the bridge is set to open at 10 a.m., at the request of the United States Coast Guard, and the bridge will be out of commission until about noon. Drivers and pedestrians are advised to use an alternate river crossing during that time, including the 11th Street, Sousa (Pennsylvania Avenue) and Whitney Young Memorial (East Capitol Street) bridges.