Abstract
This paper presents case study on one of the most challenging and India’s longest HDD crossing in mixed strata across River Brahmaputra by Horizontal Directional Drilling method by utilizing electromagnetic steering technology for pilot intersection. The present crossing falls in the state of Assam and is a part of 24″ NB × 712 km (approx.) Barauni-Guwahati cross country Natural Gas pipeline project, which is an integrated part of Pradhan Mantri Urja Ganga project and is an important link for joining North-East Gas Grid (NEGG) to rest of the National gas grid. MECON Limited was the EPCM consultant of this pipeline crossing.
At 24″ NB × 3600m approx., this crossing has the rare distinction of being one of India’s longest HDD in mixed strata across Brahmaputra River and a hillock. The magnanimous scale of this crossing combined with 4 transition zones made it one of the most challenging trenchless crossings in recent times. We had failures but we learnt from those failures, improvised & persevered to eventually emerge successful. This paper discusses the design aspects of this crossing. The paper also talks about numerous challenges faced by this project and how they were mitigated by meticulous planning and risk management. The paper also summarizes the failures and lessons learnt from those failures.
