The main construction contract was signed last month after O’Rourke agreed to lock-in construction costs on the new 52,888-capacity Bramley-Moore Dock stadium.
Kier ranked second for the month mainly off the back of a single contract worth £460m for the A417 missing link highway upgrade between Gloucester and Swindon.
The project will see Kier and its team of Volker Fitzpatrick, Arup, Tony Gee and RPS design and construct 3.4 miles of new dual carriageway.
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According to data compiled by construction information specialist Barbour ABI, Kier’s big road win last month catapulted the firm to the top of the annualised contracts league for work won over the last 12 months pushing Wates into second and BAM into third place.
Among the other big contract wins during the month, Vistry Partnerships signed a £150m deal to deliver 805 homes at Top Wighay Farm in Hucknall, Nottinghamshire for the County Council.
Kent-based RG Group sealed the deal to deliver a 488-home build-to-rent scheme in Manchester’s Piccadilly East neighbourhood for developer Olympian Homes.
Winvic secured the £100m first phase of Peel Group’s, 1m sq ft speculative multi-shed scheme in Milton Keynes.