The southbound lane in the 700 block of Massachusetts has been shut down since early Friday morning following a water main break, according to Mike Lawless, assistant utilities director for the city of Lawrence.

Traffic is being re-routed at the Massachusetts Street intersections at both Sixth and Eighth streets.

Lawless said a leak in a fire line midway down the 700 block of Massachusetts street was the cause of Friday’s problems. The lane was still closed Friday evening.