Roads and highways are always very important projects for any country and an index of its development. Their planning, designing, construction and maintenance are among the major duties of civil engineers the world over. As with any other civil engineering project, geological investigations play important role in the design, stability and economical construction and maintenance of the roads. An ideal site for the construction of a bridge in is the one across the valley cut in a sound rock and where the river flow is free from scouring due to bends, tributaries and other causes. The foundation of bridge piers and abutments require a serious geological investigation. Pressure from bridge and running water are the main lateral forces. Piers should be founded at depth safe from scouring erosion.
