It will likely be 2022 before the Athy Southern Distributor Road is opened.
Cllrs. were issued up-dated time-lines at a special meeting yesterday.
The scheme was first mooted in the 1970s; planning permission was granted last year.
Soil sampling along the route will begin in March, and will be followed by an archaeological assessment in April.
Labour Cllr. in the Athy Municipal District, Mark Wall, says the next phase will begin in May, on the "Kilkenny side" of the project.
Stock image: road construction.