Heavy Water Plant at Tuticorin employs the ammonia-hydrogen mono-thermal exchange process to produce Nuclear Grade Heavy Water. The plant is integrated with Southern Petrochemical Industries Pvt. Ltd. (SPIC) and is located at a distance of about 14 km from Tuticorin Railway Station in the state of Tamilnadu. Work on HWP Tuticorin was commenced in September 1971 and the plant was commissioned in July 1978.

The production at Tuticorin plant had to be stopped in 2007 after about three decades on account of SPIC stoppage. It is now under revival as the integrated fertilizer plant has resumed operations.

To meet the requirements of 2nd stage Indian Nuclear Power Program(INPP), work is in progress to set up Solvent Production Plant for production of organo phosphorus solvents.