The Tamil Nadu government has announced a proposal to construct a 92-kilometre-long elevated coastal road along the East Coast Road (ECR), linking Ennore Port in North Chennai to Poonjeri near Mamallapuram in the south. Estimated to cost Rs 27,600 crore, the sea flyover is being positioned as a key infrastructure intervention to tackle mounting traffic issues and improve connectivity between Chennai and its fast-expanding southern suburbs.
According to officials familiar with the matter, the project—tentatively named the ECR Sea Bridge—is currently in the advanced planning stage. An initial outlay of Rs 3.80 crore has been approved to carry out a feasibility study. This assessment will consider environmental, technical, and financial aspects of the project, and determine its alignment, construction strategy, and likely socio-environmental impacts. Once the report is submitted and approvals are obtained, work is expected to commence in phases.
Three-Phase Construction Strategy
The sea flyover project is being planned in three distinct phases. The first phase is expected to cost Rs 5,400 crore, the second Rs 9,000 crore, and the final stretch will require an estimated Rs 13,200 crore. The precise lengths and geographic boundaries of each phase have not been disclosed yet, but the government has stated that the project will follow an integrated coastal alignment, largely paralleling the existing ECR corridor.
A senior official in the State Highways Department indicated that the alignment has been designed to run parallel to the coast while avoiding ecologically sensitive zones to the extent possible. The state has committed to adhering to the guidelines laid down by the Coastal Regulation Zone (CRZ) authority, and has reportedly begun preliminary consultations with the Ministry of Environment, Forest and Climate Change (MoEFCC) for obtaining clearances.
Connectivity, Freight Movement and Urban Decongestion
Once completed, the sea flyover is expected to serve multiple objectives. First, it aims to significantly reduce vehicular congestion on the existing East Coast Road and Old Mahabalipuram Road (OMR), which are frequently choked during peak hours. Second, it will serve as a dedicated corridor for smoother movement of freight traffic, especially between the Ennore and Kattupalli ports in the north and industrial zones located in Oragadam, Sriperumbudur, and Mahabalipuram.
According to state officials, the flyover will also support the Chennai Metropolitan Development Authority’s (CMDA) plans to decongest central Chennai by diverting port-related and long-haul vehicular traffic to peripheral routes. This is in line with the Tamil Nadu Infrastructure Development Board’s ongoing focus on multimodal connectivity and logistics integration, particularly through coastal corridors.
Parallel Developments: Chennai Peripheral Ring Road
In tandem with the ECR Sea Bridge, the state is pushing ahead with the Chennai Peripheral Ring Road (CPRR), a 120-kilometre greenfield expressway project connecting Ennore Port to Mahabalipuram via key industrial and tourism centres including Sriperumbudur, Kancheepuram and Thiruporur.
Together, the CPRR and the ECR sea flyover are expected to form a dual transport spine for Chennai’s long-term urban expansion and logistics infrastructure. Both projects are aligned with the central government’s push for coastal economic corridors and port connectivity under the PM Gati Shakti initiative.
Environmental Concerns and Regulatory Oversight
Despite the logistical benefits, the project has drawn attention from environmental researchers and marine conservationists. Concerns have been raised regarding its potential impact on the fragile coastal ecosystem, especially in areas where Olive Ridley turtles are known to nest during the breeding season. Environmental impact assessments (EIA) and public consultations are likely to be key hurdles the project will need to navigate before receiving a final go-ahead.
The government has responded by assuring that construction methods will incorporate environmentally sensitive techniques such as elevated piers and pre-cast segments to limit seabed disturbance. The exact methodology, however, will depend on the findings of the feasibility and impact studies, which are expected to be completed by early next year.
Funding and Implementation Challenges
A project of this scale will require significant financial commitment. The Tamil Nadu government is exploring various funding models, including public-private partnerships (PPP), viability gap funding, and international infrastructure loans. A finance department official stated that discussions with multilateral lending agencies are underway, though a formal investment framework has not yet been announced.
Experts have noted that land acquisition may not be a major hurdle since much of the proposed alignment runs offshore or along existing public corridors. However, construction challenges, particularly those related to working in saline coastal environments and ensuring resilience to cyclonic events, are expected to influence design and timelines.
Possibility of National-Level Precedent
If implemented successfully, the Chennai sea flyover could become a model for coastal urban infrastructure in other Indian cities facing similar traffic and connectivity issues. The project has already drawn comparisons to global examples such as the Hong Kong–Zhuhai–Macau Bridge and Vietnam’s coastal expressways, though Tamil Nadu officials maintain that the project is tailored to local traffic and environmental conditions.
Whether the ECR Sea Bridge will materialize as proposed depends on the results of the feasibility study, public feedback, and the ability to secure adequate funding. For now, it represents one of the most ambitious infrastructure proposals in the state’s recent history, with the potential to alter mobility patterns and urban development across Chennai’s coastal zone.
