SEMARNAT Orders New Impact Statement for Puerto Nuevo Manzanillo

Mexico’s Ministry of the Environment (SEMARNAT), through its Directorate General for Environmental Impact and Risk (DGIRA), has closed and archived the Environmental Impact Assessment (EIA) procedure for the project “Development of the New Port of Manzanillo, in Basin II of the Cuyutlan Lagoon, Manzanillo, Colima,” promoted by ASIPONA Manzanillo. 

In Official Letter SRA/DGIRA/DG-10367-25, DGIRA issued an agreement declaring the procedure concluded due to the “material impossibility” of continuing it and ordered the case file to be archived as closed. At the same time, SEMARNAT informed the project sponsor that, based on the agency’s review of the proposed modification, it must submit a new Regional Environmental Impact Statement (MIA-R) to seek authorization for the revised version of the project.  

According to the project’s MIA-R executive summary, “New Port Manzanillo” was presented as a major expansion of port infrastructure in Basin II, structured in two broad stages. The concept included dredging and land reclamation, sheet piling or containment structures, platforms for specialized container terminals (TEC), a berth for PEMEX, and supporting works such as road links, rail tracks, and utility networks. The documentation estimates dredging of 113.535 m³ of sediments and the engagement of roughly 5,500 workers.  

The same file places estimated investment at MX$131.86 billion (US$7.63 billion), and references federal investment executed by ASIPONA Manzanillo through the federal ports authority structure cited in the document.  

The Redesign that Triggered the Closure

The file indicates that after DGIRA issued an additional information request on Oct. 20, 2025, ASIPONA Manzanillo submitted, on Dec. 5, 2025, a proposed design alternative aimed at reducing impacts on mangroves.  

SEMARNAT’s resolutive document describes the alternative as a comprehensive reconfiguration of the port compared with the original layout. It involved changes to the physical and operational organization of the design, including the relocation of platforms associated with TEC and the fuel storage and distribution terminal referenced in the file (TAD). The proposal also sought to modify dredging alignments, turning basins, and navigation channels to avoid affecting “Islas Cocodrilos I and II,” as outlined in the documentation.  

A comparative table included in the resolutive file shows how the revised footprint and the associated request for forest land-use change (CUSTF) would shift under the modification. The document reports the overall project area changing from 447.47ha to 521.47ha, while the surface linked to CUSTF would decrease from 139.68ha to 50.50ha.  

DGIRA’s assessment states that, even if the modified works were framed within Basin II, the reconfiguration would introduce impacts that were not previously assessed. The agency highlights that the revised infrastructure would involve an area of interconnection with Basin I, which could affect lagoon dynamics by reducing water-flow communication and sediment transport as described in the resolutive text.  

Based on that analysis, SEMARNAT concluded that the modification falls under the scenario set out in the applicable EIA regulation (the resolutive document cites Article 27, Section II), meaning the revised project must be evaluated through a new MIA-R rather than being processed as an adjustment within the existing procedure.  

What this Means Next

With the procedure closed and archived, the path forward depends on the sponsor submitting a new Regional EIA that reflects the modified design and supports DGIRA’s review of the updated impacts, mitigation measures, and environmental management commitments. The agency’s decision also underscores how substantive project redesigns can trigger a reset of the permitting track when the modified works alter the scope of impacts compared with what was originally assessed.  

Mexico’s Port Modernization

The permitting reset comes as Mexican authorities have been outlining a broader strategy to modernize the national port system. In July, officials presented a plan targeting six ports, among them Manzanillo-Cuyutlan, aimed at boosting maritime competitiveness, upgrading logistics infrastructure, and attracting record levels of public and private investment.

For Manzanillo, the government has presented an expansion narrative anchored on making the port the leading container gateway in Latin America, alongside a portfolio of public works and private terminal investments. The public component includes the relocation of a PEMEX terminal (MX$994 million), reported as launched in March 2024 and targeted for completion in October 2027, and the development of Puerto Nuevo in the Cuyutlan Lagoon, where authorities have described dredging works beginning in July 2025 as part of a MX$18.7 billion effort with a July 2027 completion goal. Plans presented publicly describe five terminals, each with 1,500m of quay and 100ha of land, alongside expanded customs, roads, and rail access.

Private investment has been described as flowing into specialized container terminals in two phases. Phase one would deliver Terminals 2 and 3 after public land preparation (MX$358 million, September 2025–May 2026), followed by private construction (MX$40.9 billion, May 2026–May 2028). Phase two would add Terminals 4, 5 and 6 after public preparation (MX$400 million, September 2026–January 2028) and private development (MX$47.6 billion, March 2028–September 2030). Additional projects presented for the existing San Pedrito terminal include MX$676 million to rehabilitate a mineral terminal used by Peña Colorada and MX$3.04 billion for a CONTECON Manzanillo expansion.

Separately, authorities have also framed Puerto Nuevo Manzanillo as a flagship long-term infrastructure initiative blending public and private capital, with sustainability positioned as a central design objective. Plans described publicly have referenced a total buildout toward 2030, a Basin II footprint spanning 1,800ha, and an ambition to scale capacity toward 10 million containers per year, alongside hydrocarbon storage infrastructure, including a PEMEX-operated terminal with 3.7 million barrels of capacity, plus an existing liquefied gas terminal, MBN reports.