The Can Gio-An Hung-Dien Thinh-Lam Vien consortium said the overall length of the project would remain about 14.06 km despite adjustments to the tunnel, bridge and approach roads.
Under the revised proposal, the submerged tunnel section would increase from 2.1 kilometres to about 3 kilometres, lifting the total tunnel length from 3.1 kilometres to nearly 3.85 kilometres.
The sea bridge section would also be extended by about 200 metres to more than 8 kilometres, including over 5 kilometres on the Can Gio side and nearly 3 km on the Vung Tau side.
Meanwhile, the total length of approach roads at both ends would be reduced from nearly 3 kilometres to about 1.9 kilometres.
The route is planned as a six-lane road, with the tunnel section measuring 30.2 metres wide and the bridge section 26.25 metres wide.
Total investment for the project is estimated at around VND 93 trillion (USD 3.6 billion), including more than VND 9.2 trillion in construction loan interest costs.
The consortium proposed developing the project under a build-transfer contract, under which investors would fully finance construction and land clearance costs, with repayment made through land allocations and state budget funds of equivalent value.
Under the revised timeline, approvals for the investment policy and feasibility study are expected in the second quarter of 2026, with construction scheduled to begin in the third quarter after site clearance.
The project is expected to be completed and operational by the third quarter of 2029.
Can Gio and Long Son-Vung Tau have strong potential for eco-tourism, ports and logistics development, but the two coastal areas still lack a direct transport link, with travel currently relying on National Highway 51 or ferry services taking 90-120 minutes.
Authorities say the project would shorten travel times, support development in Can Gio and Long Son, improve access to the Cai Mep-Thi Vai port cluster and ease congestion on National Highway 51.