Lead in Tap Water, Ranked: EPA Numbers for All 25 of America's Biggest Cities

We pulled the EPA's lead test results — the Lead and Copper Rule 90th-percentile numbers utilities are required to report — for the water systems serving all 25 of America's largest cities.

The headline: nobody is over the federal action level. The spread underneath it is the story. New York City's latest number is 10 parts per billion — two-thirds of the current limit, the highest of any big city, and exactly at the stricter limit that takes effect in 2027. Seven cities report zero.

All 25 biggest cities, ranked by lead in tap water

Most recent EPA-reported lead 90th percentile for each city's water system. The current federal action level is 15 ppb.

Rank	City	System	Lead 90th percentile	Year
1	New York	New York City System	10 ppb	2024
2	Chicago	City of Chicago	8.8 ppb	2025
3	Boston	MWRA	5.9 ppb	2025
4	Indianapolis	Citizens Water	5.2 ppb	2025
5	Houston	City of Houston	5.0 ppb	2024
6	Denver	Denver Water	3.9 ppb	2025
6	Los Angeles	LADWP	3.9 ppb	2023
8	Fort Worth	City of Fort Worth	3.0 ppb	2025
9	Phoenix	City of Phoenix	2.7 ppb	2024
10	Las Vegas	Las Vegas Valley Water District	2.1 ppb	2025
11	Philadelphia	Philadelphia Water Department	2.0 ppb	2025
11	Washington, DC	DC Water	2.0 ppb	2025
13	Seattle	Seattle Public Utilities	1.6 ppb	2025
13	San Antonio	San Antonio Water System	1.6 ppb	2024
15	Jacksonville	Jacksonville	1.5 ppb	2023
16	El Paso	El Paso Water	1.2 ppb	2025
17	Dallas	City of Dallas	1.1 ppb	2024
18	Nashville	Metro Water Services	0.8 ppb	2025
19	San Francisco	SFPUC	0 (non-detect)	2024
19	San Diego	City of San Diego	0 (non-detect)	2023
19	San Jose	San Jose Water	0 (non-detect)	2025
19	Austin	Austin Water	0 (non-detect)	2024
19	Columbus	City of Columbus	0 (non-detect)	2025
19	Oklahoma City	Oklahoma City	0 (non-detect)	2025
19	Charlotte	Charlotte Water	0 (non-detect)	2025

Every system name links to its full page — every contaminant it reported, not just lead — and all of them are on the map.

New York has been at 10 ppb for 25 years

New York City's 90th percentile has not come in below 10 ppb in any EPA-reported round since 1999. It touched the action level itself four times between 1999 and 2007, and hit 19 ppb — an exceedance — in 2010. The 2024 number, 10 ppb, ties the city's best in that entire series. It is also exactly the number the EPA just made the new limit: under the Lead and Copper Rule Improvements finalized in October 2024, the action level drops from 15 to 10 ppb in 2027. If New York's number doesn't move, the biggest water system in the country will be sitting precisely at the line.

Chicago is the other one to watch, for the opposite reason: its trend points up. From 5.6 ppb in 2021 to 8.8 in 2025 — a 57% rise across five reporting years, against a backdrop of the same rule's new requirement that cities replace their lead service lines.

The fixable-problem file

The same EPA series, run backwards, is the strongest argument that these numbers respond to treatment:

• Boston (MWRA): 48 ppb in 1997 — the worst reading of any of these systems, ever — down to 5.9 today.
• Columbus: exceeded the action level in four separate rounds (as high as 41.6 ppb in 2007). Latest round: non-detect.
• Washington, DC: 39 ppb in 1992 and 35 ppb in 2001, at the start of the lead crisis that rewrote federal reporting rules. Today: 2.0.
• Denver: 17 ppb in 2012, 3.9 today.
• Philadelphia: 22 ppb in 1992, 2.0 today.

Corrosion control works. Every one of those recoveries came from changing the water chemistry so it stops dissolving the pipes — the lead lines themselves are mostly still in the ground, which is why the numbers need watching.

Just outside the top 25

Five more major systems for context: Detroit at 7.5 ppb (2025) would rank third if it were a top-25 city. Milwaukee reported 5.3 (2023), Portland 4.9 (2025), Memphis 4.7 (2025), Baltimore 2.7 (2024). Portland's is the most recent big-city action-level exceedance in the data — 21 ppb in 2021.

One aside from the EPA's violation records: across all 30 systems here, only two carry an open health-based violation, and neither is about lead. New York and Portland are both listed under the surface-water treatment rules — New York for an uncovered finished-water reservoir, Portland for treatment it is still building — both open since 2017. We ranked drinking water violations by state separately.

How to read these numbers honestly

This is worst-case sampling, by design. The Lead and Copper Rule makes utilities sample homes most likely to have lead — houses with lead service lines or lead solder — and report the 90th percentile. So "10 ppb" means: among the riskiest taps sampled, 10% measured higher than 10 ppb. It's a stress test of the distribution system, not an average of what the city drinks.

Zero doesn't mean lead-free. A non-detect 90th percentile means at least 90% of worst-case taps had no detectable lead. Individual homes can still have it, because lead almost never comes from the treatment plant — it leaches from the service line and the plumbing between the main and your faucet. Two houses on the same block can differ.

Under the limit is not the same as safe. The action level is a treatment trigger, not a health threshold; the EPA's stated health goal for lead is zero. That's the entire reason the limit is dropping to 10 ppb in 2027 — and by that standard, the gap between New York's 10 and Charlotte's zero is not a rounding error.

Every number above is the EPA's own reported Lead and Copper Rule summary statistic (SDWIS), year noted per city. Look up any system in the country — yours included — on the map, or start with the lead pillar page for what the measurements mean.