Park River Auxiliary Tunnel

Application of new geotechnical concepts, adequate subsurface information, and flexible specifications should reduce the cost of tunneling. Computer programs were utilized to optimize the tunnel configuration and design section. Multiple designs were bid to obtain the least cost of construction. To date, the following lessons have been learned in the design and construction of the Park River Auxiliary Tunnel: (1)The use of new design tools and construction equipment, if properly utilized, should reduce the cost of tunneling; (2)the selection of the tunnel alinement should be based on geologic data to obtain the best ground conditions for tunneling; (3)adequate subsurface data should be used to optimize the design; and (4)bidding should be flexible enough to allow for contractors' input.