Date
Monday, July 28, 2025
Time
11:00 AM - 11:30 AM
Location Name
Ballroom C
Name
A New Era for Chattanooga's Sewer Rehab Program: How the Pandemic and AI Changed the Strategy
Track
Collections
Description
Once known as the “Dirtiest City in America”, Chattanooga has been busy cleaning itself up over the last several decades and is now one of the most livable, fastest growing mid-sized cities in the Southeast. One way the city has been cleaning itself up is through its efforts to eliminate Sanitary Sewer Overflows (SSOs) over the last 10 years as part of its ClearChattanooga program.
Like many other cities across the country, Chattanooga’s old and deteriorating sewer infrastructure along with regional growth was causing significant SSO’s which were impacting its streams and rivers. In 2013, the City negotiated a settlement with the EPA and entered into a Consent Decree (CD) which became known as “ClearChattanooga” – an ambitious 17-year, $1 billion program to accelerate its much-needed sewer infrastructure upgrades to ultimately reduce or eliminate SSOs and improve the operation of its sewer system.
A key component of the ClearChattanooga program’s SSO reduction goals is a two-phased SSES & rehab program that consists of condition assessment of over 1.9 million linear feet (LF) of sewers and targeted rehabilitation of 29 sewer basins within the 17-year period.
Phase 1 began in 2013 and included the condition assessment of 250,000 linear feet (LF) of sewers within the top 5 priority sewer basins. This initial phase was completed in 2019 with over 100,000 LF of sewers rehabilitated. Each basin was executed as a standalone project and utilized the traditional design-bid-build model.
As the ClearChattanooga program was preparing to begin Phase 2 in early 2020, the global pandemic caused significant disruptions to the industry’s workforce and created market volatility which resulted in skyrocketing construction costs. It became clear that Chattanooga would need to take a different approach to complete the remaining 24 basins in the next 10 years. To meet this challenge, Chattanooga implemented two significant changes in its strategy for Phase II.
The first change was shifting from the traditional design-bid-build model to utilizing multi-year blanket construction contracts. This approach allows for more flexibility in how the work is executed, saves time by eliminating the need for bidding projects, and minimizes the impacts of market volatility on program budgets.
The second change was the adoption of Artificial Intelligence (AI) technology. AI is enabling Chattanooga to quickly and consistently code defects from sewer inspection videos, which not only eliminates human error and bias but also allows for inspections to be completed more quickly in the field.