CMOM, FOG control, asset management, customer complaints, and public communication

CMOM turns field work into system control

Capacity, Management, Operation, and Maintenance (CMOM) is EPA's framework for managing a collection system so it has adequate capacity, is run by trained staff, is maintained before failure, and is improved on evidence. EPA's "Guide for Evaluating CMOM Programs at Sanitary Sewer Collection Systems" treats CMOM as a tool to improve Clean Water Act compliance and reduce SSOs. The exam usually tests CMOM as applied judgment, not as a definition to recite.

If a question asks what a utility should do after repeated overflows, the best answer is rarely "more emergency cleaning." It usually combines cause analysis, preventive maintenance, capacity evaluation, records, and scheduled follow-up. Watch for distractor answers that solve only the immediate symptom.

Four CMOM lenses

FOG control is source control

Fats, oils, and grease (FOG) cool and solidify in pipes, especially where flow is slow, grade is flat, or hot restaurant discharge mixes with cooler wastewater. Jetting restores flow, but the durable fix is source control. A defensible FOG program typically includes a food-service-establishment (FSE) inventory, grease-interceptor sizing requirements, an inspection frequency, pump-out records, education, and enforcement authority through the sewer-use ordinance.

Sizing context: many jurisdictions require interceptors sized so wastewater has roughly 30 minutes of retention to let grease separate, and require pump-out when accumulated FOG plus solids reach the 25 percent rule (the "one-quarter rule") of the interceptor's liquid depth. Residential outreach matters too, because household grease and "flushable" wipes add to blockages.

Asset management: make the map match reality

Collection-system assets include gravity mains, manholes, force mains, air-release valves, siphons, pump stations, wet wells, generators, controls, and flow meters. Asset management means the utility knows what it owns, where it is, its condition, its criticality, and the next planned work. For the exam, separate condition from criticality:

• A shallow dead-end line with minor roots may be poor condition but low consequence.
• A force main under a river or a pump station serving a hospital may be high criticality even before it fails.

Risk = likelihood of failure (condition) × consequence of failure (criticality). The best maintenance answer prioritizes high-risk assets, not just the worst-condition pipe.

Customer complaints are data

A complaint about odor, repeated lateral backups, or a surcharging manhole should generate both a record and a response. Collect location, time, weather, fixture or manhole observations, whether neighbors are affected, and whether the cause appears public or private (utility main vs property-owner lateral). Do not promise liability decisions in the field. Communicate only what you can verify: what you observed, what immediate action is underway, and how the customer will get follow-up. Escalate media questions, public notices, and regulatory statements to the designated utility spokesperson.

Common exam contrasts

• Reactive maintenance: crew responds only after blockages, backups, and alarms.
• Preventive maintenance: crew cleans and inspects on a schedule based on known risk.
• Predictive / risk-based maintenance: crew uses CCTV, work history, flow data, pipe age, material, and consequence of failure to rank work.
• Source control: utility reduces what enters the sewer (FOG, roots via defective laterals, sump pumps, prohibited industrial discharges).
• Capital improvement: utility rehabilitates or replaces assets when maintenance can no longer provide reliable service.

Public communication: facts, not speculation

When the public, the press, or an elected official asks about a backup, an odor, or an overflow, the operator's lane is narrow and important. State only what you can verify, describe the immediate action underway, and give a clear path for follow-up. Do not estimate cause, assign blame, predict regulatory outcomes, or promise that the utility will pay for damages; those are decisions for management, legal counsel, or the designated spokesperson.

A good field statement sounds like: "We have a crew on site, we have stopped the overflow, and our supervisor will follow up with you." That protects the customer relationship without creating liability or contradicting the official report.

During a larger event, coordinated messaging matters. The exam expects you to recognize that mixed or premature statements from different staff confuse the public and can conflict with the regulatory report. Route media calls and public-notice questions to one spokesperson so the utility speaks with a single, accurate voice.

Putting the four programs together

These programs are not separate silos; CMOM is strongest when they feed each other. A complaint log entry about repeated lateral backups (customer data) should trigger a CCTV inspection (maintenance), which may reveal a sag or grease hot spot (asset condition and FOG), which then updates the cleaning route and, if severe, the capital plan (capacity and management). The exam rewards the answer that closes this loop rather than the one that treats a complaint, a blockage, and a capital project as unrelated events.

When a question describes a recurring problem, the best answer almost always combines source control, risk-based maintenance, and documentation rather than another round of emergency cleaning.