A Crisis Beneath the Surface
The United States is facing a wastewater infrastructure crisis that most people never see. Beneath our cities and towns, an aging network of pipes, pump stations, treatment plants, and storage tanks is deteriorating at an alarming rate. The American Society of Civil Engineers (ASCE) assigned U.S. wastewater infrastructure a D+ in its 2025 Report Card.
The consequences of inaction are severe: public health emergencies, environmental contamination, regulatory penalties, and billions of dollars in emergency repairs. Understanding the risks — and the available solutions — is critical for municipalities, utilities, and industrial facility operators.
The Corrosion Problem
Corrosion can damage wastewater assets and interrupt service. The consequences depend on material condition, exposure and facility operations. A project-specific condition assessment is needed before selecting protective work.
In wastewater systems, corrosion takes several forms:
- Hydrogen sulfide (H2S) corrosion: Anaerobic bacteria in wastewater produce hydrogen sulfide gas, which converts to sulfuric acid on exposed concrete and metal surfaces. This biogenic sulfuric acid attack can destroy inches of concrete in just a few years.
- Microbially induced corrosion (MIC): Bacteria colonies that form on pipe and tank surfaces create localized corrosion cells that eat through metal and concrete from the inside out.
- Chemical corrosion: Treatment chemicals, including chlorine, caustic soda, and ferric chloride, corrode the very infrastructure they're meant to protect when containment coatings fail.
- Erosion corrosion: High-velocity flows carrying abrasive grit and debris wear away protective surfaces and accelerate material loss.
Aging Infrastructure: The Scale of the Problem
EPA's 2022 Clean Watersheds Needs Survey identified $630.1 billion in needs over 20 years. This figure covers broader clean-water needs, not only maintenance of existing wastewater systems.
The problem is compounded by population growth, which increases demand on systems that are already strained. Older treatment plants often lack the capacity, technology, and structural integrity to meet modern standards. When these facilities fail, the results can be catastrophic.
Real-World Consequences of Failure
Wastewater infrastructure failures are not hypothetical. They happen regularly across the country, with devastating effects:
- Sanitary sewer overflows (SSOs): The EPA estimates that 23,000 to 75,000 SSOs occur annually in the U.S., releasing raw or partially treated sewage into homes, streets, and waterways.
- Treatment plant failures: When structural elements of a treatment plant — tanks, basins, digesters, clarifiers — corrode to the point of failure, entire treatment processes can be disrupted, forcing facilities to discharge untreated or inadequately treated wastewater.
- Environmental contamination: Failed infrastructure releases pathogens, nutrients, heavy metals, and other pollutants into rivers, lakes, and groundwater, threatening ecosystems and drinking water supplies.
- Public health risks: Exposure to raw sewage causes gastrointestinal illness, skin infections, and in severe cases, outbreaks of diseases like hepatitis and cholera.
Regulatory Landscape: EPA Requirements
The EPA regulates wastewater discharges under the Clean Water Act (CWA) through the National Pollutant Discharge Elimination System (NPDES) permitting program. Facilities that fail to meet their discharge permit limits face enforcement actions including:
- Administrative orders and compliance schedules
- Civil penalties determined by the applicable requirements and circumstances
- Criminal penalties for knowing violations, including fines and imprisonment
- Consent decrees requiring facility-specific improvements
Many municipalities are currently operating under consent decrees that mandate specific infrastructure improvements within strict timelines. Failure to meet these obligations triggers escalating penalties and federal oversight.
How Protective Coatings Prevent Failures
Protective coatings and linings are the most cost-effective strategy for preventing corrosion-driven infrastructure failures. When properly specified and applied, coatings create an impervious barrier between the corrosive wastewater environment and the structural substrate.
Key coating solutions for wastewater infrastructure include:
- Epoxy coatings: High-build epoxy systems provide excellent adhesion and chemical resistance for tanks, basins, and clarifiers in moderate-exposure environments.
- Novolac epoxy coatings: Resistance to concentrated acids must be verified for the selected novolac product, concentration, temperature and exposure. Not every product suits every headworks, digester or wet-well application.
- Polyurethane coatings: Flexible and abrasion-resistant, polyurethane coatings perform well in areas subject to thermal cycling and mechanical wear.
- Ceramic-filled epoxy systems: These ultra-durable coatings combine chemical resistance with exceptional abrasion resistance, making them suitable for high-velocity flow channels and grit chambers.
- Calcium aluminate cement liners: Suitability depends on the substrate and specified product. Lining does not automatically restore structural capacity; engineering assessment and separate repairs may be needed.
The Cost of Prevention vs. the Cost of Failure
Compare project-specific scopes and estimates for protective coating, repair and replacement. Substrate condition, structural requirements, access, isolation and operating restrictions affect the options. No universal cost or penalty comparison is promised.
MPC: Your Partner in Wastewater Infrastructure Protection
Markley's Precision Company specializes in the application of protective coatings and linings for wastewater infrastructure. Our teams are experienced in confined-space work, surface preparation in corrosive environments, and the application of high-performance coating systems that meet the most demanding specifications. We help municipalities and utilities protect their critical infrastructure, extend asset life, and maintain regulatory compliance. Contact MPC to discuss your wastewater infrastructure protection needs.