Aldridge/Collisys, a Joint Venture, was the Prime Contractor on the four-track constant tension overhead contact systems portion of this 12-mile Central Corridor extension. Aldridge's scope included 16 traction power substations, an overhead catenary system (OCS) and two track tie-in to the existing Hiawatha line, communications system with fiber backbone, SCADA, CCTV, train-to-wayside communication, radio, public address system, new rail control center, train control system, wayside signals and remotely-controlled switches.