Two workmen have been injured, one seriously, while working on the A556 bypass project near Bowdon.
The workmen were helping to build a bridge when a scissor lift collapsed at around 5pm last evening.
The Health and Safety Executive have been informed and have launched an investigation.
A Highways England spokesperson said: “We are aware that two contractors were injured, one seriously, while working on the A556 Knutsford to Bowdon scheme on Monday evening.
“Our thoughts are with them and their loved ones and colleagues during this difficult time and we hope they are able to make a full recovery.
“We will fully cooperate with any inquiries as a result of this incident and it would be inappropriate to comment further at this time.”
Construction company Costain began work on the £102m project late last year.
The new four-mile road is intended to alleviate traffic on the A556 and will run between Junction 19 of the M6 near Knutsford and Junction 7 of the M56 near Bowdon.
The road will take traffic away from local villages, by-passing Over Tabley, Mere and Bucklow Hill. It will run to the west of the existing A556 and will be built below ground level where possible to minimise the impact on the surrounding area.
The road will rejoin the existing A556 for a short section near Bucklow Hill, which will be upgraded. Improvements will also be made to the layout of Junction 7 of the M56.
The new road is expected to open in 2016/17.
