Volker will reconstruct berths 201 and 202 to form a new quay in preparation for the arrival of the next generation of ultra-large container carriers at the Port of Southampton.
The initial £80m phase will involve constructing a 500m quay wall with a 16m draft.
Volker Stevin will begin work on the six-month sheet piling operation next month and is on the hunt for subcontractors to carry out earthworks, demolition, dredging and concrete piling.
Dredging works to widen and deepen parts of the main approach channel between the Isle of Wight and the port are awaiting approval by the Marine Management Organisation.
The remaining £50-£70m in the port budget will be spent later on increasing berths 204 and 207.