Wastewater Treatment in the United States: Current Needs and Strategic Imperatives in 2025

Executive Summary

The United States faces mounting challenges in managing its wastewater treatment infrastructure. Decades of underinvestment, evolving environmental threats, and stricter regulations have created an urgent need for strategic upgrades and modernization. Approximately 34 billion gallons of wastewater are generated daily, yet a significant portion remains untreated or improperly treated due to aging infrastructure and stormwater overflow. This report outlines the national status of wastewater treatment, identifies key inefficiencies, highlights new regulatory trends, and presents strategic pathways for long-term resilience.

Overview of U.S. Wastewater Infrastructure

According to the U.S. Environmental Protection Agency (EPA), over 16,000 publicly owned treatment works (POTWs) operate across the country, processing an estimated 34 billion gallons of wastewater per day (EPA, 2024a). However, the average age of these facilities exceeds 40 years, and many were not designed to handle current volumes or the increasing presence of industrial and emerging contaminants.

Key Challenges

Investment Requirements

The EPA’s Clean Watersheds Needs Survey estimates a need for over $271 billion for wastewater infrastructure improvements over the next two decades (EPA, 2024a). When including stormwater systems, nonpoint pollution controls, and decentralized treatment, total estimated needs exceed $630 billion.

Aging and Overburdened Infrastructure

Many treatment plants are past their useful lifespans, leading to reduced efficiency and increased failure rates. Combined sewer systems (CSOs), still in use in over 700 municipalities, frequently overflow during storms, discharging untreated wastewater directly into surface waters (ASCE, 2023).

Environmental and Climate Pressures

Climate change exacerbates existing system vulnerabilities, particularly during high-precipitation events. In Louisiana, Hurricane Francine overwhelmed wastewater systems, prompting water-use restrictions and raising concerns about contaminant release (Axios, 2024).

Regulatory and Funding Gaps

Though the Infrastructure Investment and Jobs Act allocated historic funding to water infrastructure, it still falls short of the EPA’s documented needs. Additionally, rapid evolution in pollution standards—especially around contaminants like PFAS—has placed new demands on systems without corresponding regulatory clarity or funding (NAWC, 2024).

Wastewater Treatment Gaps and Regulatory Expansion

Volume Treated and Reused

Roughly 81% of U.S. wastewater receives secondary or higher-level treatment (EPA, 2023a). However, only 6–8% of treated wastewater is reused—primarily in arid regions for irrigation and industrial cooling—despite greater potential (EPA, 2023b).

Untreated or Improperly Treated Wastewater

The U.S. discharges an estimated 850 billion gallons of untreated sewage into the environment each year due to infrastructure failures and CSO events (EPA, 2023a). In addition, the EPA has identified that approximately 15% of households use decentralized septic systems, many of which are aging, failing, or improperly maintained, thereby threatening surface and groundwater quality (USGS, 2023). Furthermore, even among treated wastewater, many plants continue to exceed pollutant limits for nitrogen, phosphorus, pharmaceuticals, and industrial chemicals, particularly during storm surges or high inflow periods (EPA, 2023c).
 
 Industries Newly Regulated by EPA

In response to rising pollutant loads, the EPA is expanding its Effluent Guidelines Program. The following industries are now subject to increased monitoring or proposed new discharge standards:

 Landfills and Leachate Systems: High concentrations of metals, ammonia, and emerging contaminants.
 Textile and Carpet Manufacturing: PFAS and dye pollutants.
 Food and Beverage Processing: Especially dairy and meat processors, due to high BOD/COD content.
 Pharmaceutical and Biotech Facilities: Solvent and active compound discharges.
 Cannabis Cultivation and Processing: High nutrient and pesticide runoff.
 Semiconductor and Battery Manufacturers: Metals and toxic process chemicals (EPA, 2024b).

These expansions aim to address sectors that were either historically under-regulated or have seen rapid recent growth without corresponding wastewater controls.

Emerging Solutions and Innovations

To address the widening treatment gap, municipalities and private entities are adopting:

 Decentralized and Modular Treatment Units: Ideal for new developments and rural communities.
 Wastewater Treatment as a Service (WTaaS): Outsourced, performance-guaranteed treatment with tech-enabled monitoring. Contact us to know more about this!
 Advanced Treatment Technologies: Including membrane bioreactors, UV oxidation, and activated carbon for PFAS removal.
 Public-Private Partnerships (PPPs): To accelerate capital project deployment and compliance performance

Strategic Recommendations

1. Expand Federal and State Funding to accelerate system rehabilitation and treatment upgrades.
   
2. Enforce Industrial Accountability through updated EPA effluent rules targeting high-impact sectors.
   
3. Promote Water Reuse and Recycling by incentivizing dual-pipe systems and industrial greywater adoption. Contact us to help you with this!
4. Scale Decentralized Systems to relieve overburdened central infrastructure.
5. Integrate Digital Infrastructure for real-time treatment monitoring and early-warning systems.
   

References
 U.S. Environmental Protection Agency (EPA). (2023a). Clean Watersheds Needs Survey.
 U.S. Environmental Protection Agency (EPA). (2023b). National Water Reuse Action Plan. https://www.epa.gov/waterreuse
 U.S. Environmental Protection Agency (EPA). (2023c). NPDES Compliance Reports. https://www.epa.gov/npdes
 U.S. Environmental Protection Agency (EPA). (2024a). Infrastructure Investment Needs Overview. https://www.epa.gov/cwns
 U.S. Environmental Protection Agency (EPA). (2024b). Effluent Guidelines Program Plan 15. https://www.epa.gov/eg
 American Society of Civil Engineers (ASCE). (2023). Report Card for America’s Infrastructure. https://infrastructurereportcard.org
 United States Geological Survey (USGS). (2023). Septic System Impacts on Water Quality. https://www.usgs.gov
 Axios. (2024). Hurricane Francine and Climate-Driven Sewer Overflows. https://www.axios.com
 National Association of Water Companies (NAWC). (2024). 2024 Regulatory Year in Review. https://nawc.org