Gas leaks demand immediate action. Whether caused by aging infrastructure, environmental factors, or accidental damage, they pose serious risks to public safety, utility providers, and surrounding communities.
Traditional gas leak repair methods on distribution assets often require large-scale excavation, prolonged road closures, and significant disruptions.
Utility providers face a difficult balancing act: ensuring public safety while minimizing service interruptions. However, utilities with cast iron pipelines across major cities, gas leak response needs a smarter, faster, and less disruptive solution, so gas utilities can reduce leak backlogs and reduce the impact the repairs have on O&M budgets.
The Role of Robotics in Pipeline Emergency Response
When you think about robotics, plants and assembly lines usually come to mind. However, outdoor robots have started to play a major role in pipeline emergency response, too.
Instead of relying on traditional methods of cast iron gas main leak repair, which requires one excavation over every joint, utilities can use pipeline robotics to repair joints from within the pipe itself. This internal joint repair process minimizes environmental impact, reduces costs, and significantly speeds up leak repairs.
Take the ULC Technologies CISBOT (Cast Iron Sealing Bot) for example. CISBOT is a robotic system that travels within live cast iron gas distribution mains to internally seal leaking joints and prevent future leaks. From one excavation, the robot can seal over 1,400ft (130+ joints) of critical infrastructure.
By using robotic technology, gas utilities can respond quickly to pipeline failures without tearing up streets or disrupting communities.
How CISBOT Enhances Cast Iron Gas Main Leak Response
Across the US, thousands of gas leaks happen every year, causing billions of dollars in damages, roadway closures/traffic congestion, and gas service shutdowns. While some leaks are high risk and need immediate emergency repair, most leaks are smaller and require the utility to monitor for changes in gas readings over time.
As with most problems, gas leaks are easier to fix when addressed as quickly as possible, which takes us to our first point.

1. Fix Multiple Leaks Through One Excavation
When a gas leak occurs, traditional repair methods often require crews to excavate multiple locations along a pipeline to pinpoint and fix the issue. This means road closures, lengthy repair times, and potential hazards for workers and the public as traditional joint repair requires an excavation over each joint
CISBOT eliminates these inefficiencies by accessing the pipeline through a single small excavation. Once inside, the robot travels hundreds of feet in either direction from the point of entry, identifying the leaking joints, lining up the tool head with laser-guided precision, and sealing them with an industry-proven anaerobic sealant.
Gas utilities will often see multiple gas readings along the gas main. Due to budgetary restrictions, the utility may opt to only repair the larger leak and then continue to monitor the gas readings until a repair is required or mandated. With CISBOT, the utility can fix all the leaks from a single excavation—drastically reducing the number of excavations required.
Real-World Example
During an emergency repair project with Cadent Gas, CISBOT was deployed to address a high-risk pipeline leak beneath a busy city center. Instead of weeks of disruption, the robotic repair process was completed in just days, with minimal street closures and reduced environmental impact.
2. Integrate Proactive Joint Sealing into Reactive Leak Response
Cast iron gas main leak response is typically viewed as a reactive measure to address gas readings. From the traditional perspective, the utility won’t go through the expense and disruption to excavate and repair a joint that is not leaking.
Technology like CISBOT is changing that narrative.
Utilities have learned over the years that if the joint isn’t leaking now, it will eventually leak. The future risk of joint leaks will eventually translate to more excavation that hits O&M budgets that are already spread thin.
While inside the pipeline to repair leaking joints, utilities are using CISBOT to proactively seal additional joints. This helps spread out the costs of the excavation, fitting, tapping and other expenses among multiple joints — effectively delivering the lowest cost per joint and supporting future O&M cost avoidance.
3. Supporting Gas Main Modernization Programs
Gas distribution utilities continue to invest heavily in gas main replacement programs to reduce the volume of cast iron and bare steel gas mains. These programs can have upwards of 20-30 years remaining, which leaves the utility continuing to support leak response.
CISBOT is helping gas utilities extend the usable life of 12”-48” diameter cast iron gas mains, which helps keep joints free of leaks between now and when the pipeline is eventually replaced.
4. Access Additional Budgeting Options for Leak Response
Cast iron gas main leak repairs are typically seen as an O&M expense due to the reactive nature of the work. Many gas utilities that utilize CISBOT are able to justify using capital funding and include work scope for CISBOT as part of approved rate cases and price control periods due to the proactive nature of the work.
Deployment of CISBOT to reinforce multiple joints on a segment of gas main reduces future excavations required for leak response. Assuming all joints in the main will leak at some point in time, CISBOT requires one excavation to seal up to 130 joints versus the need for 130 potential excavations over the remaining life of the asset.

Real-World Applications of CISBOT in Emergency Pipeline Response
ULC Technologies has successfully deployed CISBOT in emergency gas pipeline repair scenarios across multiple regions.
Cadent Gas Emergency Response – Manchester, UK
In early 2023, Cadent Gas used CISBOT to rapidly seal a critical pipeline joint failure beneath Manchester’s busy streets. Traditional methods would have taken weeks, but with CISBOT, the emergency gas leak repair was completed in a fraction of the time with minimal disruption to the public.
Read more about Cadent Gas and CISBOT.
Union City, NJ – Emergency Gas Leak Repair with CISBOT
In another case, ULC’s robotic solution was used to secure a failing gas main beneath a high-traffic urban area. Without CISBOT, utility crews would have needed to shut down multiple blocks and disrupt thousands of commuters. Instead, CISBOT’s precision repair ensured the pipeline was stabilized quickly and efficiently.
Learn about CISBOT’s role in Union City.
Wrapping Things Up
Robotics technology for utility companies is a fairly new domain, and we’re proud to be on the leading edge, helping our clients be the pioneers that keep their communities safe while streamlining their operations and reducing costs.
Interested in using CISBOT for pipeline repair? Reach out.