You Just Lost 25 Percent of Your Raw Water Supply. Now What?

The North Texas Municipal Water District's (NTMWD) Lake Texoma Water Supply Project designed in the late 1980's and completed in 1991, conveys approximately 25 percent of NTMWD's total raw water supply. The project consists of a 72-inch pipeline from Lake Texoma to a discharge point at Sister Grove Creek approximately 30 miles to the south of Lake Texoma. Sister Grove Creek then flows into Lavon Lake to the south. The 72-inch pipeline also supplies water to the City of Sherman, Texas' water treatment plant. Zebra Mussels were found in Lake Texoma in 2009 and represented the first time this invasive species was found in Texas waters. Because the water from Lake Texoma was being transferred from the infested Red River to the un-infested Elm Fork of the Trinity River, the United States Army Corps of Engineers required NTMWD to cease pumping operations until a solution to mitigate the spread of the zebra mussel could be found. To compound this situation, 2010-2011 was one of the worst drought periods this area of the state had ever experienced and NTMWD's other raw water supplies were stressed. On October 1, 2011, with multiple options having been studied to re-establish the Texoma supply, NTMWD embarked on the selected project. This project entails extending the existing Lake Texoma pipeline system another 47 miles to the south to bypass Lavon Lake and connect directly to the head works of NTMWD's four water treatment plants in Wylie, Texas. The total program cost exceeds $300 million. The goal was to have water flowing into the water treatment plants by August 2013, less than 2 years after the project's inception. This paper provides a general overview of the components of the project and the approaches that were implemented to fast-track this critical project. These approaches included fast-tracking the typical design schedule, aggressive right of way acquisition, and the use of a Construction Manager at Risk to accelerate the execution of the project.