Full Lead Service Line Replacement Is Closer Than We Thought
On November 25, 2025, EPA released the Federal Fiscal Year 2025 Drinking Water State Revolving Fund (DWSRF) Lead Service Line (LSL) grant allotments to states, including reallotments of prior year funds. EPA’s announcement also included updated national inventory data and expanded eligibility for the use of Infrastructure Investment and Jobs Act (IIJA) LSL funding.
One promising development coming out of the EPA announcement is the sharp decline in estimated LSLs nationwide. Initial Lead and Copper Rule Revisions (LCRR) inventory submissions suggest that the national total number of LSLs may be less than half of what was previously projected, signaling a potentially faster path to full replacement.
A Lower National LSL Estimate - With Important Caveats
EPA now estimates 4 million LSLs nationwide, based on initial inventory data provided by water systems and compiled by states, as required by the LCRR. This is a dramatic reduction from the 9.2 million estimate derived from the updated Drinking Water Infrastructure Needs Survey and Assessment (DWINSA) released in 2024.
This new estimate is encouraging, suggesting that we may be able to remove all LSLs faster, fully, and forever– sooner and at a lower price tag than expected. However, this lower count reflects a key assumption: If a state did not submit inventory data for a given water system, EPA considered all of that system’s service lines as non-lead. While this approach may underestimate the true national LSL burden, it also creates an incentive for more complete inventory reporting.
But the very good news is that LCRR inventories indicated that most states had moderately to substantially fewer LSLs than previously expected (blue dots in Fig. 1). Alaska, Oregon, and Florida saw the most dramatic shifts, with reductions in estimated LSLs ranging between 95% -100%. In Florida’s case, this likely reflects corrections to flawed survey data from 2024. Other states with notable reductions include Ohio and Illinois, two heavily lead-burdened states that reported nearly half the number of LSLs initially expected.
Only five states—Texas, Michigan, Kansas, Nebraska, and Mississippi—reported higher LSL counts, though the magnitude of these increases was relatively small. Notably, Texas saw the largest change, with an additional 119,145 LSLs, representing nearly a 5% increase (download our data to explore more). This uptick may stem from the state’s previous restrictions around the use of predictive modeling for inventories. Solely relying on more time- and labor-intensive physical verifications could contribute to a larger number of unknowns, particularly in large systems, which could lead to inflated LSL estimates as shown in our previous analyses.
Figure 1. Most states saw dramatic reductions in the estimated number of LSLs (blue dots). Comparison between estimated lead service lines (LSL) counts as determined by the updated 7th Drinking Water Infrastructure Needs Survey and Assessment (DWINSA, x-axis) and the Lead and Copper Rule Revisions service line inventories (LCRR, y-axis). Dots below the dotted line represent states whose updated estimate is lower than initially expected, while dots above the line indicate states with more LSLs than previously expected.
What These Shifts Mean for LSL Replacement
The lower national LSL estimates are encouraging. Some western states, like Oregon, New Mexico, Hawaii, and others, appear to have very few remaining lines and may be able to complete full replacement within the next year or even sooner. It’s also reassuring that states where we expect the heaviest LSL burdens, such as those with older housing stocks, continue to report comparatively higher LSL counts.
Most importantly, because the remaining rounds of IIJA funds are now tied to these updated inventories, resources will flow faster and more directly to the communities with the greatest documented lead burdens.
We’ll break down the specifics on how the new LSL estimates impact IIJA LSL allotments in our next blog.