SOUTH FORSYTH — Forsyth County commuters will begin to see their tax money put to use Monday as work to begin the widening of Ga. 400 will get under way.

But, as expected, the major traffic artery may get worse before it gets better as lane closures will be required.

According to the state Department of Transportation, one lane of the corridor in Forsyth will close overnight from 9 p.m. to 5 a.m. throughout the week as soil samples are gathered.

Weather permitting, the northbound left lane and shoulder will be closed at the Big Creek Bridge on Monday, just north of McFarland Parkway (Exit 12). Tuesday night, the left lane and shoulder heading south at the bridge will be closed.

Wednesday night, work will occur in the median, for which no lane closures will be needed.

On Thursday night, crews will begin by closing the northbound left lane and shoulder at the Sawnee Creek Bridge between Exits 15 and 16.

According to the DOT, as northbound work finishes “around midnight, the work will move” across the highway to the southbound left lane and shoulder at Sawnee Creek.

Teri Pope, a district communications officer with the DOT, said the samples are required to design the new, wider road and bridges.

“Engineers are determining the specifics of widening 400, from the type and strength of concrete to use in the bridges to the drainage structures that will direct water flow and every detail of the road and bridges,” Pope said.

“The samples taken next week will give us the data to finalize the bridge design based on the soil and structure of the existing bridge structures.”

The project will add an additional lane on Ga. 400 in the existing median from McFarland Parkway to Hwy. 369 (Browns Bridge Road). That’s nearly nine miles farther north than the original reach to Bald Ridge Marina Road (Exit 15).

At least three lanes currently flow on either side of the highway from McFarland Parkway south into Fulton County.

The 13.4-mile, $47.4 million construction cost is primarily being funded through a 2014 voter-approved transportation bond referendum. The state is expected to contribute $10 million.

Rudy Bowen, DOT board member for the 7th Congressional District, said in a statement that the county’s “leadership stepped up to the plate last year, deciding to take control of their future mobility through a transportation bond.”

“The people of Forsyth are purposefully investing in their own infrastructure,” he said.

C.W. Matthews Contracting Co. is expected to break ground in early November.