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What is the infrastructure of the United States? There are highly visible components, like bridges, roads, ports, railroads, or even electrical grids. But Americans interact with one essential component on a daily basis, and it’s in critical condition: the ability to access, consume, and use clean water.

According to the Environmental Protection Agency (EPA), the cost of installing new drinking water infrastructure and rehabilitating, expanding, or replacing existing infrastructure over the next 20 years will total $625 billion — an increase of 32% from four years ago.

How the federal government assesses drinking water infrastructure

Every four years, the EPA conducts the Drinking Water Infrastructure Needs Survey and Assessment (DWINSA).[1] This report is used to update the infrastructure needs that are “necessary over the next 20 years for water systems to continue to provide safe drinking water to the public.”

What does the latest assessment say?

The financial need for drinking water infrastructure is on the rise. More than two-thirds of the $625 billion in estimated improvements is needed to distribute and transmit drinking water to homes.

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Although medium-sized water systems represent about 12% of the country’s total, they account for 44% of the financial need identified in the survey. These systems serve between 3,301 to 100,000 people.

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States with higher populations have the most need for water infrastructure investment.

The most populous states have the highest financial needs for water infrastructure improvements. In fact, California and Texas combined account for almost a quarter of the total financial need identified by DWINSA. Here are the top 10 states by needed investment in the next 20 years:

  • California – $83.52 billion
  • Texas – $61.25 billion
  • New York – $35.15 billion
  • Florida – $26.75 billion
  • Pennsylvania – $24.30 billion
  • Illinois – $22.21 billion
  • North Carolina – $20.00 billion
  • Georgia – $19.66 billion
  • Washington – $16.32 billion
  • Michigan – $16.26 billion

Addressing the significant challenge of lead

The latest DWINSA was the first to include an evaluation of the cost to replace lead service lines (LSLs[2]), the lead pipes that connect a water main to a building’s plumbing. Replacing LSLs significantly impacts the costs for water distribution and transmission improvements. A single LSL replacement costs up to $12,300. The assessment estimates that there are a total of 9.2 million lead service lines in the US, with Florida and Illinois projected to have more than one million each.

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Lead services lines in Florida and Illinois also account for nearly a quarter of the nation's total LSLs.

Projected number of lead services lines and percentage of national total by state
State Lead service lines Percent of US total
Florida 1,159,300 12.62%
Illinois 1,043,294 11.35%
Ohio 745,061 8.11%
Pennsylvania 688,697 7.50%
Texas 647,640 7.05%
New York 494,007 5.38%
Tennessee 381,342 4.15%
North Carolina 369,715 4.02%
New Jersey 349,357 3.80%
Wisconsin 341,023 3.71%

Both the EPA and the US Department of Housing and Urban Development have encouraged communities to prioritize infrastructure improvement projects which remove LSLs and reduce lead exposure. Lead in water can lead to a number of health concerns, and the Centers for Disease Control and Prevention has stated that “all sources of lead exposure for children should be controlled or eliminated.”

What doesn’t the DWINSA assessment cover?

In addition to potential sources of lead, the EPA is also investigating the impact of PFAS in the American water supply. PFAS are sometimes called “forever chemicals” or “forever plastics.” While DWINSA does not currently include any estimates or assessments related to infrastructure to mitigate these chemicals, preliminary research concludes that PFAS are present in American water supplies. The EPA plans to further investigate the level of exposure in public water supplies and how harmful PFAS are to people and the environment.

Finally, approximately 43 million people in the US rely on private wells for drinking water. These sources are not regulated by the federal government and are not included as part of the DWINSA survey. The United States Geological Survey’s National Water Quality Program is responsible for investigating the quality of water pumped from these domestic wells. However, no federal agency routinely tests these wells.

Where does this data come from?

The most recent edition of the EPA’s DWINSA — the largest and broadest since it was established in 1995 — is based on data from 3,526 public water systems from all 50 states, Puerto Rico, Washington, DC, and US territories, including systems serving Tribal lands. The results of the DWINSA inform the EPA’s recommendations related to the 2023 Drinking Water State Revolving Fund, which distributes finances to state and local governments to undertake drinking water infrastructure projects. The funds are secured under the Infrastructure Investment and Jobs Act (IIJA), which was signed into law in November 2021 and allocated $55 billion to expand access to clean drinking water.

Learn more about which cities have health issues with their water and the facts about public water system inspections. Get data directly in your inbox by signing up for our newsletter.

Drinking Water Infrastructure Needs Survey and Assessment
Last updated
September 2023

The EPA has been working closely with water systems and states for over 25 years to conduct the DWINSA. The survey and its methodology are widely accepted and often cited in various literature and studies. The DWINSA collects actual project and asset data from a random statistical sample of water systems, which minimizes bias and uncertainty in the survey and results. Rigorous water system project documentation is required based on a weight of evidence approach to demonstrate that a project is necessary, feasible, and has commitment. Consequently, the survey is credible, defensible, and statistically significant.


The service line questionnaire was optional; however, 75% of water systems provided responses about their service lines. To date, this is the best available data collected and assessed on service line materials in the US.