The Boise Warm Springs Water District is the oldest operating geothermal water system in the United States and has a water temperature of 176 degrees Fahrenheit. The 12-inch mainline is deteriorated and is in need of repair before a complete failure occurs. Planning for the project included hydraulic modeling of the systems water mains and services lines in an effort to determine the quantity of water that the system can provide for heating and domestic use. The project will replace approximately 4,900 feet of the asbestos main distribution trunks that feeds the entire system with geothermal HDPE pipe.