Gifford India has been commissioned by IL&FS Infrastructure Development Corporation for the Government of the State of Bihar.
The flood plain of the River Ganges in this region is 10km wide and the bridge is likely to be at least 5km between abutments.
Ground conditions consist of fine silty sands extending to significant depths. Strong currents pick up this fine material causing "scour", which is a problem for any supports within the river and caissons for bridge construction will require sinking to depths of more than 60 metres.
The proposed bridge is part of a project to provide a new road link between Bakhtiyarpur, south of the Ganges, with Sahpur Pataori to the north and Gifford’s study will include the associated road infrastructure. Gifford engineers will establish the optimum alignment for the crossing. Traffic studies, hydraulic modelling and geotechnical investigations are due to start in the next few weeks.
Bihar has a population three times that of the UK and is situated in the north east of India and borders Nepal. The Ganges is one of India’s major rivers rising in the Himalayas and passing through the plains of Bihar and Bengal before discharging in the Bay of Bengal at Kolkata.