SOMERSET — At long last, the reconstruction of Route 138, the town’s second busiest street, is set to begin.

Town Administrator Dennis Luttrell said yesterday that the contractor, LAL Construction of Fall River, told him the work will commence immediately after the July 4th weekend.

The entire project, from Route 6 north, isn’t expected to be completed until a year from this winter. Construction will shut down during the coldest months.

The Board of Selectmen have given permission for LAL to do some of the work after dark, but don’t expect any nighttime activity soon, said Luttrell.

Workers must first mill the existing roadway, digging it up and grinding it down — a very noisy process that isn’t conducive to sleeping.

“The paving, which is a lot quieter, will be done at night,” Luttrell said.

The project also includes drainage improvements, new curbing and five-foot-wide sidewalks.

There are no detailed plans for the sidewalks, so in many cases it will be up the contractor to accommodate phone poles and other obstructions. “They’ll adjust in the field to existing conditions,” said the administrator.

LAL is doing the project for $2,879,000.

Route 138, which includes County Street and part of Riverside Avenue, is a bumpy mess because MassHighway announced in 1999 that it would be repaving the highway, the town scrambled to excavate and replace utility lines first, and the state then reneged on its pledge, saying it could be years before money could be found for the project.

Selectman Lorne Lawless personally lobbied Governor Patrick to find funds, and both state Sen. Joan Menard and state Rep. Patricia Haddad pushed to convince Commissioner Luisa Paiewonsky to earmark money to fix the road.

The highway is so bumpy, rescue trucks avoid it when they transport anyone with back problems.

gemery@projo.com