The Papua New Guinea (PNG) Department of Works (DoW) has appointed Australian consultant SMEC to carry out a hydrological investigation for a new bridge over one of the world’s fastest-flowing rivers.
A new crossing is needed of the Buso River in Morobe Province as major flooding caused extensive damage to the existing bridge. The DoW has proposed the design and construction of a new multi-span structure with intermediate piers.
Prior to undertaking design work, the DoW has engaged SMEC to undertake hydrologic and hydraulic investigations. The study is intended to assist in identifying options for the optimum site and will provide essential data to enable a bridge design and construction tender.
SMEC’s services will include determining the Buso River catchment area and assessing rainfall intensities, flood levels and flow velocities for return periods of 20, 50, 100 and 2,000 years, taking climate change impacts into consideration. The work will also include modelling of the river crossing site including a 20m-wide debris mat restricting water flow at each intermediate pier.
Other tasks include identifying the susceptibility of riverbanks to erosion; recommending appropriate upstream and downstream river training works; and preparing a report outlining the results and recommendations of the hydrologic and hydraulic investigations.