Monday, September 9, 2024
11:00 AM - 11:30 AM
Double Trouble – Failure and Triumph under the Holston River

KUB previously utilized a 30” water line and a 20-inch sewer force main that crosses under the Holston River in East Knoxville. Both lines were installed by horizontal direction drill (HDD) in the late 1990’s. In May of 2023, the 30” water line catastrophically failed under the river leaving only a single water feed to KUB’s to customers including critical industrial and wholesale customers. KUB learned that the force main had failed shortly after learning that the waterline had failed. Within hours of each failure KUB had isolated the lines, and in the case of the sewer force main, began a 24-hour pump and haul operation to keep sewer system in operation. KUB quickly retained the services of Garney Construction and Hazen and Sawyer to assist in addressing one of their largest system failures. The water line failure resulted in extremely low pressures throughout the east side of their system and limited capacity. These sudden failures posed an imminent threat to water supply and wastewater management in KUB’s affected service area and the selected team immediately began to work on a swift and effective solution through the following process: 1. Damage Assessment: A thorough evaluation of the extent of the damage to water and sewer lines, utilizing advanced inspection technologies and underwater survey techniques. 2. Emergency Repairs: Implementation of rapid-response measures to address the failures, including the deployment of specialized teams, equipment, and materials to conduct repairs on the water lines while minimizing disruption to the surrounding ecosystem. 3. Environmental Impact Mitigation: Development and implementation of strategies to minimize environmental impact during the repair process, such as sediment control measures, water quality monitoring, and adherence to environmental regulations. 4. Collaborative Stakeholder Engagement: Establishment of effective communication channels with local authorities, environmental agencies, and the community to ensure transparency, provide regular updates, and address concerns throughout the emergency repair process. Within less than a month of the initial water line failure, a new 18” water line was in services and operational under the Holston Reiver proving service to KUB’s affected customers. Less than two weeks later, a new 18” sewer force main was installed on the river bottom of the Holston and connected to the existing force main reinstating pumped sewer flow. By assembling the right team and leveraging resources, technology, and forward think, KUB and their team were able to quicky formulate and execute a solution to one of their most significant failures with minimal disruption to utility service and the environment.