Ministers yesterday finally approved plans for a lock and flood control system to allow barges to travel from the Thames to London's Olympic Park.
The announcement moved the Olympic Delivery Authority (ODA) a step closer to it ambitious target of moving half of all London 2012 construction freight traffic by rail and water. There had been doubts about whether the £18.9M package of works to control water levels on the River Lea would receive all the funding it needed (NCE 18 January). But client British Waterways yesterday announced that contractor Volker Stevin had been awarded the job on a design and build basis, after reaching a funding agreement with the Department for Transport, London Thames Gateway Development Corporation, the ODA and Transport for London. 'Without this structure, the ODA had no chance of ever achieving that 50% [freight] target,' said British Waterways London director Mark Benstead. 'But the main reason for this structure is its legacy.' The main £15M structure at Prescott Channel will consist of a 62m long by 8m wide tidal lock, two 8m wide radial floodgates and a bypass weir. The lock's main purpose is to control the tidal flow of the Thames into the River Lea so two 350t barges can pass through it at once. But the River Lea is a fluvial flooding outlet and while the floodgates will have a default vertical position, they will be fitted with semi-buoyant tanks to allow additional flood water to pass underneath. In extreme floods, the gates can be lowered into a horizontal position on the river bed. Additional works will include a controlled weir on Three Mills Wall River and the relocation of moorings. Construction is due to start later this month and finish in August 2008. British Waterways developed the concept design. Volker Stevin's designers are Tony Gee & Partners and Bennett Associates. The project is due for completion in August 2008.