The £600M Mersey Gateway scheme is up to about 70% of its peak workforce ahead of a busy few months for the project.
More than 700 people are currently working on the job to link Widnes and Runcorn over the famous River Mersey.
Headcount will hit 1,000 as the project peaks this autumn. Work began in spring 2014 and the bridge is expected to be open in autumn 2017.
Construction consortium Merseylink – which consists of FCC, Samsung and Kier – said it had already placed orders worth £44M with suppliers based within 30 miles (48km) of Halton.
Merseylink general manager Hugh O’Connor said: “It’s very satisfying to look at these figures and know that Mersey Gateway is providing real jobs and investment for the regional economy. These numbers will increase as we move forward.”
Halton Borough Council leader Rob Polhill said: “It has been wonderful during the past year to watch the Mersey Gateway project really pick up pace, and now we can actually see the bridge begin to take shape in the river.
“During the coming months we will be able to see more and more activity on the river as we progress the works on the main pylons.”
Thomas Duncalf, a general operative from Runcorn who is working on the project, said: “It’s a great opportunity. My grandad worked on the Silver Jubilee Bridge so this is an important part of my family history.
“I feel honoured to be part of the team building the new bridge.”