Dow Louisiana Operations (Plaquemine)
Large load · 21255 Highway 1 South, Plaquemine, LA
Dow Louisiana Operations in Plaquemine, Iberville Parish, is a chemical complex of 15 production units that make over 200 products, including caustic soda, methyl cellulose, polyethylene and chlorinated polyethylene. The Dow Chemical Company is the owner and operator of record, with Dow Inc. as parent, and Diamond Infrastructure Solutions owns the Plaquemine site. An onsite cogeneration plant supports chemical manufacturing and onsite tenants.
Overview
The 15 production units make products used in cosmetics, detergents, solvents, pharmaceuticals, adhesives, packaging plastics, automotive parts and electronics. Caustic soda is a key ingredient in products from soaps and bleach to aluminum foil, and chlorinated polyethylene made at Plaquemine goes into automotive hoses, tubes and wires. In 2017 Dow announced a world-scale EPDM plant at the site with nameplate capacity of 200 ktpa. At a December 2, 2025 community advisory meeting, Dow reported that Poly B Train 1 had been restarted and the Poly A Train had been repaired.
Profile
- Electricity and grid
- The Plaquemine facilities primarily support onsite chemical manufacturing and onsite tenants, with Entergy Louisiana supplying backup and standby power. The Dow Chemical Company has previously sold excess power into the wholesale market administered by MISO. The Plaquemine Cogeneration Facility was described by AEP as 880 megawatts, with four 170-megawatt gas-fired combustion turbine generators and a 200-megawatt steam turbine, and Dow bought it from AEP in 2006 for $64 million. FERC and EIA nameplate entries list four 198 MW generators and a 195 MW steam turbine, plus two 48.9 MW steam turbines that entered service in 2024. Olin Corporation and Blue Cube Operations hold a leasehold interest in generation capacity at the facilities, which the Louisiana Public Service Commission reduced from approximately 336 MW to approximately 285 MW.
- Ownership and permits
- The EPA registry lists The Dow Chemical Company as owner and operator and Dow Inc. as parent company. Diamond Infrastructure Solutions owns the Plaquemine site, and Macquarie Asset Management raised its minority equity stake in Diamond from 40% to 49% in September 2025. The cogeneration plant holds NPDES major permit LA0116602, and the registry lists RCRA hazardous-waste facility ID LAD008187080.
Facility
- Activity
- 15 production units produce over 200 products used in cosmetics, detergents, solvents, pharmaceuticals, adhesives, packaging plastics, autom
- Industry
- Industrial
- Site type
- Facility
- Operating status
- Operating