The concrete bridge forms part of a wider £14m regeneration plan for the harbour.
Carillion’s contract also includes improved highway access, repair of harbour walls on North and East Quay, the creation of a promenade along North Quay and flood protection works.
The works will raise the development areas above the flood level and a new highway will connect to the site of a proposed marine business park on North Quay.
The works are anticipated to take 12 months to complete.
The Hayle Harbour Primary Infrastructure Project is a public sector funded project which is essential in the delivery of the required infrastructure for the development of the proposed Marine Renewables Business Park.