The Hon'ble Prime Minister of India, Shri Narendra Modi, inaugurated the Capacity Augmentation Project of the Numaligarh-Siliguri Product Pipeline (NSPL) of Oil India Limited (OIL) during a public meeting in Guwahati on March 13, 2026. The pipeline is a 654 km long, 406 mm diameter cross-country multi-product pipeline originally designed and operated for one point seven two million (mn) metric tonnes per annum (MMTPA) and has been upgraded to five point five MMTPA to support the expansion of Numaligarh Refinery from three point zero MMTPA to nine point zero MMTPA under the Government of India's Hydrocarbon Vision 2030 for the North-East.

The capacity enhancement was achieved through upgrading of existing infrastructure, including conversion of pigging stations at Sekoni, Guwahati, Bongaigaon and Madarihat into Intermediate Pumping Stations, augmentation of pumping facilities at Numaligarh Dispatch Terminal and upgrading of facilities at Siliguri Receipt Terminal for enhanced operational efficiency and safety. Implemented as a brownfield project, the augmentation was completed within approximately Rs seven point five billion (bn) against an approved cost of Rs eight point six billion (bn), achieving substantial savings while optimising the utilisation of existing assets.

During execution the project generated significant employment with around 4.1 mn man hours over a period exceeding three years across Assam and West Bengal. The project represents a major milestone in strengthening petroleum product transportation infrastructure in the North-East region and is expected to enhance India's energy security and logistical resilience for refined products.

Oil India Limited stated through its Public Relations Department in Noida that the capacity upgrade will support the strategic objective of improving supply chains for the North-East and facilitating the refinery expansion plan. The company added that the upgrades will improve operational flexibility and safety while leveraging existing assets to deliver value to stakeholders.