The BayState Marathon and half marathon will both be held this Sunday in Lowell. Both begin at 8 am. The half marathon starts at Tsongas Center then proceeds along the south bank of the Merrimack until it crosses the Rourke Bridge and then returns along the north bank of the river to the Aiken Street Bridge. That loop is done twice with the finish line being on Arcand Drive. The marathon route starts at the same time and place but instead of crossing the Rourke Bridge, it continues on through Vinal Square, across the Tyngsborough Bridge, down the north side of the river, across the Rourke Bridge, back through Vinal Square, across the Tyngsborough Bridge again and then all the way down to the Aiken Street bridge and then to the finish line.
The BayState is a very popular road race and draws many people into the city. It does block most of the bridges across the Merrimack from early morning until early afternoon. If you don’t want to be a runner or a spectator, stay away from the Merrimack and its crossings on Sunday. I don’t know the official traffic control plan, but if you must cross the Merrimack, I believe the Bridge Street or Hunt’s Falls Bridges are the ones you will have to use.