There will be single-lane closures of the Hood River-White Salmon Interstate Bridge beginning at 8:30 on Thursday morning and continuing until work is complete, estimated to be around 5:30 p.m.  Port of Hood River officials say the single lane closure is required as the work will involve use of an inspection truck that will travel along the length of the bridge throughout the day to provide worker access underneath the bridge structure.  Flaggers will be on the bridge directing traffic around the moving work zone.    Motorists should expect delays of 20 to 40 minutes depending on traffic volume.