The notice of award was issued in December 2008 for this $144.6 million project consisting of six lined drop shafts with inside diameters ranging from 7-ft, 2-in. to 15 ft and varying in depth from 227 to 250 ft; a vent shaft; six connecting structures; three backflow gate structures; entrance conduit structures; manholes; replacement gates; the addition of 25 existing louvers at 25 existing drop shafts and 14,740 linear ft of 15-ft inside diameter lined rock tunnel.