How the San Diego County Water Authority uses data and inspection technology to guide infrastructure decisions

When Martin Coghill talks about water infrastructure, he does not start with technology. He starts with responsibility.

Coghill is the Operations and Maintenance Manager for Asset Management at the San Diego County Water Authority, where he leads a team focused on corrosion control and aqueduct integrity. Together, they help maintain a system of roughly 308 miles of large-diameter pipelines that ultimately serve about 3.3 million people across the region.

For Coghill, the scale of the system shapes every decision his team makes.

“We simply can’t afford to run our assets to failure,” he explained. “With the size of pipes involved, the consequences can be significant locally, but they can also affect the region as a whole.”

A shift from building to maintaining

Much of San Diego County’s major water infrastructure was built over decades of steady expansion, stretching from the mid-20th century through major projects completed as recently as the mid-2010s. Now, the focus is less on expansion and more on managing aging assets responsibly.

That means understanding not just how old a pipeline is, but how it is actually performing.

Coghill describes the Water Authority’s approach as risk-based asset management. Decisions about maintenance, repair, or replacement are driven by data rather than age alone.

“We base our decisions on understanding the likelihood of failure and the consequences if that failure were to happen,” he said.

The challenge of seeing what matters

One of the biggest challenges utilities face is that most degradation happens where it cannot be easily observed.

Even though the Water Authority conducts regular internal visual inspections of pipeline sections, Coghill noted that visual checks alone cannot reveal what is happening inside the pipe wall.

“We need technologies that can effectively see through the wall of the pipe,” he said. “Otherwise, you’re making decisions without a full understanding of the condition.”

That need for reliable, high-resolution information becomes even more important because pipeline defects are often highly localized. Sampling or low-resolution data may not capture the small areas where failure could begin.

When inspection data changes the outcome

Coghill shared an example that illustrates how condition assessment data can influence major financial decisions.

The Water Authority recently invested about 4 million dollars to assess the condition of 24 miles of one of its oldest pipelines, which was roughly 75 years old. Based on age alone, the pipe would normally have been considered due for replacement.

Instead, the assessment provided enough confidence to extend the pipeline’s service life by another 25 years. That effectively deferred a potential replacement cost of around 150 million dollars.

For Coghill, this is a clear example of how inspection data supports both engineering decisions and public accountability.

“It’s about spending a smaller amount to avoid a much larger premature expense,” he said.

Image courtesy San Diego County Water Authority

Why remote field testing (RFT) inspection became part of the toolkit

The Water Authority has used various inspection technologies since the 1990s, selecting different approaches depending on pipe type and expected failure mechanisms.

Remote field testing (RFT) electromagnetic inspection methods became particularly relevant when the agency needed to evaluate sections of bar-wrapped concrete cylinder pipe. Coghill explained that the team wanted a method capable of detecting issues in the steel cylinder itself, rather than relying solely on detecting reinforcing bar failures.

That decision proved important. In one inspection project, the data identified a short section of pipe with several locations where corrosion had nearly penetrated the cylinder. The problem was limited to one pipe segment, which the Authority replaced.

“If we hadn’t identified that section, it likely would have leaked within a year or two,” Coghill said.

Because the pipeline ran close to another agency’s infrastructure, the failure could have affected more than one asset.

Precision enables more targeted repairs

Detailed inspection data does not just help identify risk. It also allows utilities to make more focused repair decisions.

Coghill noted that when defects can be located precisely, repairs can often be limited to small areas rather than requiring larger replacement projects. That can reduce both disruption and cost while improving confidence in the repair strategy.

“There’s a clear relationship between the quality of the data and our ability to prioritize and plan projects,” he said.

Setting realistic expectations for technology

Despite the benefits of advanced inspection tools, Coghill emphasized that no single technology provides a complete picture.

Utilities need to understand what each method can and cannot detect, and technology providers need to communicate those limits clearly.

“The keyword for me is transparency,” he said. “A provider who’s honest about the limitations of their technology is someone I want to work with.”

He also noted that effective partnerships depend on feedback. When utilities validate findings in the field and share those results, both the owner and the provider gain a better understanding of how the technology performs over time.

Work most people never see

Much of the work involved in maintaining large transmission pipelines happens out of public view. When systems perform as expected, there is little visible evidence of the effort behind them.

Coghill said that reality shapes how his team thinks about communication as much as engineering.

He described the experience of entering the pipelines during inspections as something few people ever witness.

“It’s the darkest place you can imagine,” he said. “And if you’re the first one in, it’s also the quietest place you can imagine.”

He compared it, half-jokingly, to a sensory deprivation chamber. But the point behind the story is serious. When preventative work succeeds, nothing dramatic happens. A leak does not occur. A shutdown is avoided. Service continues uninterrupted.

Because those successes are invisible, Coghill said utilities have to work harder to explain them.

“It’s important to communicate what might have happened if we hadn’t intervened,” he said. “That’s how we build credibility with our board and with the public.”

Looking ahead

When asked what resilient water infrastructure should look like in the future, Coghill pointed to the growing role of predictive data.

Ideally, he said, utilities would have continuous insight into pipeline conditions, allowing them to plan investments further in advance rather than reacting to emerging risks.

For now, the focus remains on improving understanding of how different pipeline types age and fail, then using the best available tools to identify issues early.

“Our job is to understand those failure mechanisms and mitigate them before they become problems,” he said. “That’s the responsibility we have to the public.”