Bam’s £9m contract is just for the first phase of works, involving the refurbishment of the retained Speedwell building and the development of a new sports hall, cycle hub and car park.
The council’s design consultant Pick Everard and contractor Bam will now collaborate on  the final designs before a planning application is submitted and construction can begin.
A second phase will include the development of a 3G artificial pitch, sports pavilion and tennis courts.
There will be no swimming facilities in the first two phases but following consultation with local residents, businesses and sports clubs, plans were amended to include space for a pool at some future time.
Bam was appointed through the Southern Construction Framework.
Bam construction director Justin Price said: “We’re incredibly excited...â€
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