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Tap water report · updated November 2026

Philadelphia tap water: hard water, PFOA samples up to 8.1 ppt (EPA limit 4)

What’s in the water Philadelphia Water Department delivers to 1.6 million people, from national testing by the U.S. Environmental Protection Agency (EPA) and the utility’s own report.

Short answer

Philadelphia tap water is hard: about 8.9 grains per gallon (152 milligrams per liter (mg/L)), depending on which treatment plant serves your neighborhood (98 to 168 mg/L), according to published water quality data from Philadelphia Water Department (2024). The U.S. Environmental Protection Agency’s (EPA’s) 2024 testing found PFOA and PFOS, the two PFAS “forever chemicals” EPA limits most tightly, at 8.1 and 6.0 parts per trillion (ppt) in its highest samples, above the 4 ppt limit utilities must meet by 2029. The system had no health-based violations in the five years through September 2026.

Sources: Philadelphia Water Department 2024 data, EPA UCMR 5, EPA SDWIS 2026Q3 · Sources and method

Hardness

8.9gpg

152 mg/L

Hard

Philadelphia Water Department, 2024 data

PFAS (PFOA, PFOS)

8.1ppt

PFOA, highest sample

Above EPA’s 4 ppt limit

EPA UCMR 5, sampled 2024

Disinfectant

Chloramine

Catalytic carbon removes it

Philadelphia Water Department

Violations

0

health-based, 5 years

None on record

EPA SDWIS, through September 2026

How Philadelphia compares with the 40 systems we track

  • Hardness

    8th hardest

    of 34 systems

  • PFOA / PFOS

    4th highest

    of 11 that detected any

  • Size

    8th largest

    of 40 by people served

Compare every system in the 2026 report →

01 · What it means

What these readings mean for your home

Each reading in plain English: what it is, how Philadelphia compares with the other systems we track, and whether there’s anything to do. The tags follow EPA’s limits and reference levels where EPA has one; for hardness, which has no EPA limit, they follow the U.S. Geological Survey (USGS) scale and Minnesota’s health department. New to the acronyms? Every term, in plain English.

Hardness

Worth acting on

Hardness is dissolved calcium and magnesium, picked up as water runs through rock. It isn’t a health issue (EPA has no limit for it). It’s what leaves white crust on faucets, spots on glasses and scale inside your water heater. It’s measured in grains per gallon (gpg); 1 gpg is about 17 mg of minerals in a liter.

Here: At 8.9 gpg, Philadelphia water is hard, the 8th-hardest of the 34 systems we track. Most homes here notice scale and spotting.

What to do: A water softener is the only whole-house system that removes hardness. Size it to your household so it doesn’t waste salt.

What the research says: Studies tie hard water to more soap use and scale. Observational studies link it with somewhat more eczema in babies, but in the largest trial a softener didn’t improve existing eczema. The studies →

Learn more →

PFAS (PFOA and PFOS)

Worth acting on

PFAS are a family of thousands of manufactured chemicals used in many consumer and industrial products. They break down very slowly, which is why people call them "forever chemicals." PFOA and PFOS are the two EPA regulates most tightly. They’re measured in parts per trillion (ppt): 1 ppt is about one drop in 20 Olympic swimming pools.

Here: Philadelphia’s highest PFOA sample was 8.1 ppt, about 2 times EPA’s 4 ppt limit, the 4th-highest of the 40 we track. 11 of the 40 had a sample over the limit; 29 had none detected at all. These are samples from EPA’s 2024 testing, not a violation: utilities have until 2029 to get under the limit on a yearly average.

What to do: A filter on the tap you drink and cook from handles it. Look for reverse osmosis certified to NSF/ANSI 58, or carbon certified to NSF/ANSI 53, for PFOA and PFOS by name.

What the research says: EPA and the National Academies link PFOA and PFOS exposure to higher cholesterol, lower vaccine response, lower birth weight and some cancers, mostly over years of drinking the water. The studies →

Learn more →

Disinfectant

Nothing to do

Utilities add a small amount of chlorine, or chloramine (chlorine combined with a little ammonia), so germs can’t grow in the pipes on the way to your tap. EPA allows up to 4 milligrams per liter (mg/L) of either and says water within its standards can be used for drinking, cooking and bathing.

Here: Philadelphia uses chloramine, like 20 other systems we track. It lasts longer in pipes than chlorine and is harder to filter.

What to do: For taste, use catalytic carbon or a filter certified to NSF/ANSI 42 for chloramine. Fish tanks and home dialysis need it removed completely.

What the research says: Health agencies call these levels acceptable for drinking and bathing; dialysis and fish tanks are the exceptions. Studies haven’t shown shower chlorine harms skin or hair. The studies →

Learn more →

Health-based violations

Nothing to do

A health-based violation means the utility broke a federal drinking water rule tied to health: it went over a limit, or skipped a required treatment step. Missing a paperwork deadline doesn’t count.

Here: Philadelphia’s system had none in the five years through September 2026. That’s normal for a large system: 36 of the 40 we track had none.

What to do: Nothing to do.

Learn more →

How Philadelphia compares: highest PFOA or PFOS sample

Parts per trillion (ppt), from EPA’s 2023–25 testing. The dashed line is EPA’s limit of 4.

  1. Miami33.0 PFOS
  2. El Paso8.5 PFOS
  3. Fort Worth8.3 PFOA
  4. Philadelphia8.1 PFOA
  5. Louisville7.5 PFOA
  6. Tampa6.9 PFOS
  7. Dallas6.3 PFOA
  8. San Jose6.2 PFOS
  9. Cincinnati6.1 PFOS
  10. Columbus5.3 PFOA
  11. Austin4.8 PFOS
Each bar is one system’s highest single sample, not a yearly average. 11 of 40 systems detected PFOA or PFOS; the other 29 had nothing at or above 4 ppt. All 40 systems

If you live in Philadelphia

Philadelphia’s water is hard. Softeners from brands that sell online, at their own store prices:

02 · The full results

Every PFAS result EPA recorded

In EPA’s national testing (sampled 2024), Philadelphia’s highest samples reached PFOA and PFOS, the two PFAS “forever chemicals” EPA limits most tightly, at 8.1 and 6.0 ppt, above EPA’s 4 ppt limit. These are individual samples, not a compliance finding: water systems have until 2029 to meet the limit, judged on a yearly average.

Results from EPA’s national testing program (UCMR 5) for Philadelphia Water Department, 3 sampling points, January 2024 to October 2024. Concentrations in parts per trillion (ppt).

EPA UCMR 5 PFAS results for Philadelphia
ChemicalSamplesDetectedHighestEPA limit
PFOA (perfluorooctanoic acid)1288.14
PFOS (perfluorooctane sulfonic acid)1266.04
PFHxS120none10
PFNA1224.510
HFPO-DA (GenX)120none10

"None" means every sample was under EPA’s reporting level (4 ppt for PFOA). PFHxS, PFNA and HFPO-DA (GenX) are three other PFAS chemicals; EPA proposed removing their limits in May 2026, and that isn’t final.

03 · Where it comes from

The source, and who else drinks it

Philadelphia’s water comes from the Delaware River, treated at the Baxter plant, and the Schuylkill River, treated at the Queen Lane and Belmont plants.

Philadelphia Water Department serves about 1.6 million people directly, and 1 other water system buys water from it, serving about 822,600 more. If you live in one of them, most of what’s on this page describes your water too, though hardness and disinfectant can change if your system blends in its own wells.

Which plant serves your neighborhood decides how hard your water is: Baxter’s Delaware River water averages 98 parts per million (ppm), while Queen Lane’s Schuylkill water averages 168.

Philadelphia’s water system had no health-based violations in the five years through September 2026, according to EPA’s federal database.

Largest systems that buy from Philadelphia Water Department

  • Aqua Pa Main System822,600

From EPA’s federal drinking water database (SDWIS), 2026Q3: community systems with an active connection buying from PA1510001. Population served.

ZIP codes Philadelphia Water Department reports serving (48)

19102 · 19103 · 19104 · 19106 · 19107 · 19111 · 19112 · 19113 · 19114 · 19115 · 19116 · 19118 · 19119 · 19120 · 19121 · 19122 · 19123 · 19124 · 19125 · 19126 · 19127 · 19128 · 19129 · 19130 · 19131 · 19132 · 19133 · 19134 · 19135 · 19136 · 19137 · 19138 · 19139 · 19140 · 19141 · 19142 · 19143 · 19144 · 19145 · 19146 · 19147 · 19148 · 19149 · 19150 · 19151 · 19152 · 19153 · 19154

From EPA’s UCMR 5 ZIP file. A ZIP can be served by more than one system; your water bill names yours. Look up any ZIP.

04 · Questions

Philadelphia water questions

Is Philadelphia tap water safe to drink?

The U.S. Environmental Protection Agency (EPA) doesn’t grade a city’s tap water as safe or unsafe; it sets limits and records violations. By that record, Philadelphia’s water system had no health-based violations of federal drinking water rules in the five years through September 2026. Separately, EPA’s 2024 testing found PFOA or PFOS (two PFAS “forever chemicals”) samples above the 4 parts per trillion (ppt) limit that utilities must meet, on a yearly average, by 2029. A filter certified to NSF/ANSI 53 or 58 for PFOA and PFOS addresses it at the tap.

Is Philadelphia tap water hard?

Philadelphia tap water is hard: about 8.9 grains per gallon (152 milligrams per liter (mg/L)), depending on which treatment plant serves your neighborhood (98 to 168 mg/L), according to published water quality data from Philadelphia Water Department (2024).

Does Philadelphia tap water have PFAS?

In the U.S. Environmental Protection Agency’s (EPA’s) national testing (sampled 2024), Philadelphia’s highest samples reached PFOA and PFOS, the two PFAS “forever chemicals” EPA limits most tightly, at 8.1 and 6.0 parts per trillion (ppt), above EPA’s 4 ppt limit. These are individual samples, not a compliance finding: water systems have until 2029 to meet the limit, judged on a yearly average.

Does Philadelphia use chlorine or chloramine?

Chloramine. The Philadelphia Water Department adds chlorine and ammonia so the disinfectant lasts longer in the pipes.

Has Philadelphia’s water system had violations?

Philadelphia’s water system had no health-based violations in the five years through September 2026, according to the U.S. Environmental Protection Agency’s (EPA’s) federal database.