Construction work once again is closing a portion of a downtown street.

Crews began working Monday morning to rebuild the intersection of Seventh and New Hampshire streets. The work will prevent southbound motorists on New Hampshire Street from making a turn onto Seventh Street.

Also, no westbound traffic will be allowed on Seventh Street between New Hampshire and Massachusetts streets. Eastbound traffic on that one-block section of Seventh Street will be limited to motorists looking to park or make deliveries to businesses along the street.

Parts of the 800 block of New Hampshire Street also will be narrowed as crews begin work on installing a new mid-block crosswalk in the area. A mid-block crosswalk also will be installed in the 600 block of New Hampshire Street, although work on that part of the project has not yet begun.

Lisa Patterson, a spokeswoman with the city, expected the project to take about six weeks. Patterson urged motorists needing to enter East Lawrence to use Ninth Street during construction.