Maintenance and Reliability in Water and Wastewater Utilities

Water and wastewater utilities run critical, around-the-clock service on aging, widely distributed assets and tight municipal budgets. The reliability answer is to rank assets by criticality, monitor the few that matter most, and plan capital around the infrastructure that is wearing out, rather than spreading thin maintenance evenly across everything.

The asset base and what is at stake

A water or wastewater system is mostly pumps and motors, supported by aeration blowers, valves, screens, clarifiers, disinfection, dosing systems, and the SCADA that ties them together, much of it spread across treatment plants and remote lift stations. The service is public-health critical and tightly regulated, so a failure is not just a maintenance issue. A pump station failure can cause a sewer overflow, and a treatment failure can breach a discharge permit. That raises the stakes on reliability well above the equipment cost.

Those stakes are not abstract. The EPA estimates that between 23,000 and 75,000 sanitary sewer overflows happen across the United States every year, and they are prohibited under the Clean Water Act unless a permit authorizes them. A discharge that exceeds the limits in a utility's NPDES permit is a violation with real financial and legal consequences, and the assets that prevent these events, the collection system and treatment plants, are enormous: the EPA values the nation's sewers alone at more than a trillion dollars, spread across roughly 17,500 wastewater treatment plants. Reliability on this asset base is, in a direct sense, public-health and compliance work.

Where the failures happen

The failure list is dominated by the pumps. In wastewater, rags, wipes, and debris clog and bind pumps, one of the most common causes of station failures, and the EPA points to pipe blockages, most of them caused by fats, oils, and grease, as the leading cause of sewer overflows. Across both water and wastewater, bearing and seal wear, motor failures, and blower failures are routine. The wastewater environment adds corrosion, especially from hydrogen sulfide, which converts to acid and attacks both equipment and concrete structures from the inside. Instruments and sensors foul and drift, quietly degrading control. And in wet weather, inflow and infiltration can overload a system that is mechanically fine, pushing flows past what the stations and plant can handle. Most of these develop gradually, which makes them catchable if something is watching.

The constraints utilities work under

• Tight budgets. Municipal funding is limited, so maintenance spend has to be aimed carefully rather than applied everywhere.
• Aging infrastructure. Much of the asset base is decades old, which makes capital planning and replacement decisions central to reliability. The ASCE's 2025 Infrastructure Report Card graded the nation's drinking water a C minus and its wastewater a D plus, both unchanged since 2021, and the EPA put drinking water needs alone at 625 billion dollars over twenty years.
• Distributed assets. Lift stations and remote sites are scattered across a service area, so a failure is hard to see and slow to reach.
• Lean staff. Small teams cannot inspect everything often, which makes prioritization essential. The workforce problem is compounding: the EPA found that roughly a third of the water and wastewater workforce is eligible to retire within a decade, with a median age of 48 and only about 10 percent under 24, which means hard-won knowledge about which assets fail and how is walking out the door.

A reliability approach that fits

The reliability strategy that works under these constraints is not more maintenance, it is better-targeted maintenance.

• Lead with criticality. With a limited budget, rank every asset by the consequence of its failure and concentrate spend on the critical few whose failure causes an overflow, a permit breach, or a loss of service. A formal asset criticality ranking is what tells a lean team where to look first, and it is the same consequence-driven logic that reliability-centered maintenance applies to choosing a strategy for each failure mode.
• Monitor the critical pumps and blowers. Put condition monitoring on the rotating equipment that matters most, so bearing, seal, and motor wear is caught while it is still developing rather than after the station goes down.
• Watch the remote stations. Remote monitoring on lift stations turns an invisible failure into an early alert, which matters most where crews are far away.
• Shift from reactive to planned. Move off the reactive firefighting that a tight-staffed utility falls into and toward planned, condition-based work, which is the single biggest lever on unplanned downtime and the overflows and violations that come with it.

Aging infrastructure and capital planning

For a utility, reliability and capital planning are the same problem. No municipality can replace decades of buried and installed assets at once, so the question is which aging assets to replace first, and the answer is the ones whose failure carries the highest consequence and whose condition shows they are closest to failing. That is asset management in the sense the EPA and AWWA use the term: pairing a criticality ranking with condition assessment to direct limited capital where it protects the most service and compliance.

It is also where many utilities have the most to gain. By the ASCE's accounting, only about 30 percent of utilities have a fully implemented asset management plan, even as collection-system failures have risen from roughly 2 to 3.3 per 100 miles of pipe over the past decade. Deferring replacement on the highest-consequence assets without a plan does not save money, it trades a small planned cost now for a large unplanned one later, usually at the worst possible time.

Maintenance as compliance

For a wastewater utility, reliability and regulatory compliance are not separate goals. Most permit violations and overflow events trace back to an equipment failure that maintenance could have caught, so a maintenance program is, in practice, a compliance program. Preventing the failure is what keeps a discharge inside its NPDES limits and keeps sewage in the pipe.

The connection runs both ways. The records a maintenance program generates, the inspections done, the condition trends watched, the actions taken and when, are the evidence a utility produces in an audit or after an event to show a failure was managed rather than ignored. A program that prevents the failure but cannot show its work leaves the utility exposed on the paperwork even when the engineering was sound. This is why condition-based maintenance and a clear, retrievable record of decisions matter as much to the compliance side of a utility as to the operations side, and why the two functions are usually looking at the same assets for different reasons.

Common mistakes

• Spreading maintenance evenly. Treating a critical pump station like a minor asset wastes a tight budget and leaves the high-consequence assets exposed.
• Running lift stations blind. Without remote monitoring, the first sign of failure is often the overflow.
• Deferring on aging assets without a plan. Putting off replacement on worn infrastructure trades a small planned cost for a large unplanned one.
• Ignoring corrosion. Hydrogen sulfide damage is slow and easy to defer until it causes a failure, in equipment and in the concrete of the collection system itself.
• Treating compliance as paperwork separate from maintenance. When the maintenance program and the compliance record are disconnected, a utility can do the right work and still struggle to prove it after an event.

From scattered assets to clear decisions

Utility data is spread across SCADA, maintenance systems, and dozens of remote sites. Knowing which station or asset is trending toward a failure that would cause an overflow or permit breach, on a budget that cannot cover everything, is the hard part.

SteelTree connects to those systems and turns them into decisions: which critical assets are at risk, where the limited budget protects the most service and compliance, and the next action to take, with the reasoning attached. You keep your existing systems. SteelTree sits on top as the decision layer.

See how SteelTree turns operational data into decisions →