Bim Driven Evolution of Piling Details for the £100m Flood Defence at Boston, UK

The Environment Agency is developing the £100M Boston Barrier scheme to protect 14,000 properties from tidal flooding in Boston, Lincolnshire. In addition to two major hydraulic structures, the scheme comprises three quarters of a mile of new sheet piled river wall with a retained height typically in excess of 10 m, to allow the construction of a 2m high flood wall. The reference design comprised two main standard details and this paper describes the evolution of these concepts through detailed design into seven standard details to overcome space constraints, temporary works interactions, buried obstructions and anchorties of the existing quay wall as well as to optimise for buildability. In addition to the river walls, the paper also describes the use of a large-scale zone load test to demonstrate that a piled foundation was not needed for the barrier control building resulting in the elimination approximately 70 piles with reduction in risk associated with buried obstructions whilst piling on the Port of Boston estate. The paper demonstrates the value of a 3D BIM model in drawing together designer, constructor, owner and other key stakeholders to develop consensus and buy in for the developing design solutions.