wastewater infrastructure

Wastewater

D+

Overview

The nation’s more than 16,000 wastewater treatment plants are functioning, on average, at 81% of their design capacities, while 15% have reached or exceeded it. Growing urban environments signal a trend that these facilities will increasingly accommodate a larger portion of the nation’s wastewater demand. Though large-scale capital improvements have been made to systems experiencing sanitary sewer overflows, efforts have slowed in recent years. As many treatment plants and collection networks approach the end of their lifespans, the financial responsibilities for operation and maintenance will become more costly. Estimates indicate that utilities spent over $3 billion in 2019, or more than $18 per wastewater customer to replace the almost 4,700 miles of pipeline nationwide. Recently, the more prevalent use of asset management plans enables 62% of surveyed utilities to proactively manage wastewater infrastructure maintenance rather than reactively respond to pipeline and equipment failures. In 2019, though the annual water infrastructure capital investment gap was $81 billion, the sector has made strides to address current and future needs through resilience-related planning and innovations that produce profitable byproducts or cost savings from wastewater treatment.

Download Report
wastewater infrastructure

Introduction

A critical component that influences the well-being of any community is its system for removing and treating wastewater for the protection of human and environmental health. Wastewater infrastructure includes a network of sewer pipes that collect and carry household, business, and industrial effluents to wastewater treatment systems — onsite or centralized facilities. Within these treatment systems, wastewater undergoes processes to remove harmful constituents and reduce pollution to the Environmental Protection Agency (EPA) and/or state-regulated levels prior to being discharged into nearby waterbodies or, in some cases, recovered for water, energy, and nutrient reuse. 

Highlights

Approximately 20%

of Americans rely on septic tanks.

The nation’s wastewater footprint

includes over 800,000 miles of public sewers

and 500,000 miles of private lateral sewers.

Most wastewater treatment plants

are designed with an average lifespan

of 40 to 50 years.

wastewater infrastructure

Capacity & Condition

There are more than 16,000 publicly owned wastewater treatment systems of various sizes serving the majority of wastewater needs in the United States. The remainder of the population — approximately 20% of Americans — rely on onsite wastewater systems such as septic tanks.

Explore Capacity & Condition

Operations & Maintenance

Wastewater infrastructure may be owned by a public, private, or cooperative entity, and the operation and maintenance (O&M) may be conducted by the same party or subcontracted elsewhere. As utilities face the challenges of meeting increasingly stringent water quality regulations, funding significant infrastructure replacements, and/or affordably providing services amid growing public and environmental health risks, the option of merging (utility consolidation) may unlock financial, technical, and managerial resources to meet current needs and adapt to future demands.

Explore Operations & Maintenance

Funding & Future Need

Wastewater infrastructure may be funded by local user fees and taxes, state-specific grants or discretionary set-asides, and federal grants or financing mechanisms. Funding and financing differ through the simple fact that infrastructure financing, like any loan or bond, requires repayment over a 30- to 50-year period.

Explore Funding & Future Need
wastewater infrastructure

Public Safety & Resilience

In some communities where legacy infrastructure exists, wastewater and stormwater systems are integrated into a combined sewer network. When these areas experience heavy rainfall or rapid snowmelt, the capacity of the combined system is overtaxed and results in combined sewer overflows where large volumes of partially treated or untreated wastewater bypass the treatment process and enter local waterbodies. According to the EPA, there are approximately 860 combined sewer systems throughout the country. Over the last two decades, more than 200 of the nation’s largest combined sewer systems (those serving > 50,000 people) have been identified and had actions taken to reduce overflow discharges that degrade water quality. 

Explore Public Safety & Resilience

Innovation

Water Conservation and Monitoring Sensors

Across all sizes of wastewater treatment systems, technological and scientific innovations have made significant contributions to addressing the sector’s challenges. For example, water conservation appliances have reduced the volume of wastewater entering the system, treatment process innovations have more efficiently utilized existing capacity and limited resources, and real-time conveyance network monitoring can pinpoint and prioritize areas suffering from inflow and infiltration or in need of O&M. 

Sensors and monitoring innovations are being installed to collect real-time data on the wastewater conveyance network’s condition to inform and prioritize the system’s O&M schedule. After a wastewater utility in San Antonio, Texas, implemented in-pipe sensors, data was collected to optimize the network’s cleaning schedule, saving thousands of dollars in each location a sensor was installed. 

Additionally, in recent decades, resource recovery has increasingly shifted the traditional wastewater treatment mindset away from generating a product solely for disposal but reconceptualizing this “waste” as a “resource.” Innovations such as anaerobic digestors, indirect potable reuse, and biosolids reuse systems can recover water, energy, and nutrients from treated wastewater and may contribute to the resilience of treatment facilities, communities, and entire watersheds.

Raising the Grade

Solutions that Work

Infrastructure owners should engage in asset management practices across infrastructure sectors to extend the lifespan of assets and prioritize limited funding. Asset management must include continuous assessment of the condition of assets and prioritize investment decisions based upon a comprehensive suite of data.

More collaborations between researchers, technologists, wastewater utilities and operators, and federal decision-makers will be needed to develop and quickly deploy regulations, systems, public safety education, and policies that address 21st century concerns such as per- and polyfluoroalkyl substances (PFAS, forever chemicals) or novel biological components.

Expand EPA’s CWSRF program and the Water Infrastructure and Finance Innovation Act (WIFIA) with additional long-term, low-cost funding mechanisms for regionally and nationally significant, large-dollar-value projects.

Identify new grant programs and funding mechanisms whose goal is to eliminate and/or decouple the nation’s remaining combined sewer systems.

Develop a federal grant pilot program for publicly owned wastewater treatment plants whose purpose is to create or improve waste-to-energy systems that increase wastewater treatment efficiency.

Incorporate geographically specific, projected impacts of climate change into wastewater infrastructure planning and long-term funding decisions.

Utilities should ensure their rates cover the full cost of service including operations, maintenance, and capital needs; clearly communicate rate increases to the public; and balance local issues of affordability.

As all wastewater systems face multiple and increasing natural threats, a rule similar to America’s Water Infrastructure Act of 2020 should be implemented to direct utilities to develop, update, and implement vulnerability (risk and resilience assessments) and emergency response plans.

View Report Sources

U.S. Environmental Protection Agency, “Septic Systems Overview.”
The World Bank Group, “Population Growth (Annual %) – United States.”
Pew Research Center, Social & Demographic Trends, What Unites and Divides Urban, Suburban and Rural Communities, May 22, 2018.
Interview with Bluefield Research Group on “Segmenting Utility CAPEX – U.S. Municipal Water Infrastructure Forecast,” September 2019.
U.S. Environmental Protection Agency, Office of Research and Development, “State of Technology for Rehabilitation of Wastewater Collection Systems,” July 2010.
South Dakota Department of Environment and Natural Resources, Division of Environmental Services, “Recommended Design Criteria Manual,” March 1991.
U.S. Environmental Protection Agency, Office of Research and Development, Office of Water, “Onsite Wastewater Treatment Systems Manual,” February 2002.
Construction Dive, “NAHB: The Median Age of US Housing Continues to Climb.”
Tabuchi H, New York Times, “$300 Billion War Beneath the Street: Fighting to Replace America’s Water Pipes,” November 10, 2017.
Interview with Bluefield Research Group on “Underground Infrastructure: U.S. Water & Wastewater Pipe Network Forecast, 2019-2028,” November 2019.
U.S. Environmental Protection Agency, Office of Wastewater Management, Office of Water, “Primer for Municipal Wastewater Treatment Systems,” September 2004.
U.S. Environmental Protection Agency, Office of Research and Development, Water Supply and Water Resources Division, “National Database Structure for Life Cycle Performance Assessment of Water and Wastewater Rehabilitation Technologies (Retrospective Evaluation),” January 2014.
U.S. Environmental Protection Agency, “Former National Compliance Initiative: Keeping Raw Sewage and Contaminated Stormwater Out of Our Nation’s Waters.”
U.S. Environmental Protection Agency, Enforcement and Compliance History Online.
US Water Alliance, “Utility Strengthening Through Consolidation: Guiding Principles for the Water Sector,” 2019.
The United States Conference of Mayors, “Local Government Makes Record-High Investments in Public Water & Sewer Infrastructure.”
U.S. Environmental Protection Agency, Septic Systems, “Why Maintain Your Septic System.”
Black & Veatch Management Consulting, LLC, 2018-2019 “50 Largest Cities Water & Wastewater Rate Survey,” 2019.Water Works Association, “AWWA Utility Benchmarking: Performance Management for Water and Wastewater,” 2019.
Interview with Bluefield Research on “Underground Infrastructure: U.S. Water & Wastewater Pipe Network Forecast, 2019-2028,” published November 2019.
Congress of the United States, Congressional Budget Office, “Federal Support for Financing State and Local Transportation and Water Infrastructure,” October 2018.
American Society of Civil Engineers, “The Economic Benefits of Investing in Water Infrastructure: How a Failure to Act Would Affect the U.S. Economy Recovery.”
Congressional Research Service, “Federally Supported Water Supply and Wastewater Treatment Programs,” May 3, 2019.
The United States Conference of Mayors, “$125.5 Billion – Record Spending on Municipal Water and Sewer by Cities in 2017,” November 1, 2019.
The National Association of Clean Water Agencies, “Cost of Clean Water Index,” 2018.
Black & Veatch Management Consulting, LLC, 2018-2019 “50 Largest Cities Water & Wastewater Rate Survey,” 2019.
The United States Conference of Mayors, “$125.5 Billion – Record Spending on Municipal Water and Sewer by Cities in 2017,” November 1, 2019.
U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, “Water and Wastewater Annual Price Escalation Rates for Selected Cities Across the United States,” September 2017.
The World Bank, “Wastewater: A Resource that Can Pay Dividends for People, the Environment, and Economies, Says World Bank,” March 19, 2020.
Research Service, “Federally Supported Water Supply and Wastewater Treatment Programs,” May 3, 2019.
Society of Civil Engineers, “The Economic Benefits of Investing in Water Infrastructure: How a Failure to Act Would Affect the U.S. Economy Recovery.”
U.S. Environmental Protection Agency, National Pollutant Discharge Elimination System (NPDES), “Combined Sewer Overflow Frequent Questions.”
U.S. Environmental Protection Agency, Enforcement, “Former National Compliance Initiative: Keeping Raw Sewage and Contaminated Stormwater Out of Our Nation’s Waters.”
U.S. Environmental Protection Agency, PFOA, PFOS and Other PFASs, “Basic Information on PFAS.”
U.S. Environmental Protection Agency, Science Inventory, “Detection of Emerging, Clinically Relevant Antibiotic Resistance Genes in Wastewater from Treatment Plants in Urban and Rural Areas in the United States.”
American Society of Civil Engineers, “The Economic Benefits of Investing in Water Infrastructure: How a Failure to Act Would Affect the U.S. Economy Recovery.”
Water Environment Federation, “Current Priority: PFAS.”
U.S. Environmental Protection Agency, “Case Study and Information Exchange.”
Committee on Adaptation to a Changing Climate, Ayyub BM, ed., “Climate-Resilient Infrastructure: Adaptive Design and Risk Management,” Published online October 2, 2018.
U.S. Environmental Protection Agency, Water Resilience, “America’s Water Infrastructure Act: Risk Assessments and Emergency Response Plans.”
Water Online, “‘Massive Savings’ Earn SAWS Recognition as Insightful Utility and Among Top 10 Utility Papers Presented At WEFTEC19*,” September 26, 2019.
U.S. Environmental Protection Agency, “Mainstreaming Potable Water Reuse in the United States: Strategies for Leveling the Playing Field,” April 2018.
The Water Research Foundation, “Resource Recovery.”


PHOTO ATTRIBUTES

1. Photo by Caroline Sevier 

2. Photo by Ivan Bandura

Sign Up for Email Updates

Sign Up For Email Updates - Footer Popup

Select your home state, and we'll let you know about upcoming legislation.
  • Are you a current ASCE member?
  • This field is for validation purposes and should be left unchanged.

Back