Lake Tawakoni Water Supply Project, Critical Path Issues and Lessons Learned: Fast-Tracking a USD100 million Water Transmission Project

摘要

Since its formation in 1951, the North Texas Municipal Water District has been charged with developing a reliable water supply source for its 13 member cities and 46 other customers (some direct and some indirect), including more than 1.5 million people in portions of north Texas including portions of Collin, Dallas, Denton, and Kaufman Counties and all of Rockwall County. Recent long-range water supply planning efforts have identified significant increases in water demands that must be met through a corresponding increase in available raw water supply. Compounding the need for raw water is the fact that the North Texas region is currently in the second year of a drought that is the worst on record since the 1950s, with the District's primary water supply reservoir, Lake Lavon, falling some 17 feet in water surface elevation since mid-2005. In an effort to supplement available supplies, the District contracted for 50,000 acre-feet of water per year from the Sabine River Authority in Lake Tawakoni, located approximately 45 miles east of Dallas in October 2005. Given current drought conditions and ominous rainfall forecasts, the District has requested that the infrastructure needed to transfer this water from Lake Tawakoni to Lake Lavon be in service no later than October 1, 2007, to prevent further water restrictions and possible water rationing. The infrastructure needed includes approximately 30 miles of 54 and 60-inch-diameter transmission pipeline and two pump stations, each with a raw water pumping capacity of 75 MGD. The estimated project cost is USD100 million. Critical path issues for meeting the highly accelerated schedule include overall project team coordination; route selection; environmental permitting considerations; easement and property acquisition; power supply; equipment delivery; and construction of multiple project components simultaneously. The focus of this paper is to discuss the critical path issues and offer lessons learned from fast-tracking the design and construction of a multi-million dollar water transmission project.