Drinking Water

Quality Report

We have three drinking water treatment plants in Philadelphia…

2023 • Published in 2024

PWD’s Public Water System Identification # PA1510001

City of Philadelphia & Philadelphia Water Department

…But our water quality story is bigger than our borders.

A message from the Commissioner

Top-quality water means protection from source to tap.

Since upstream threats can impact drinking water downstream, our staff members are dedicated to safeguarding these source waters.

On water’s journey to you, we utilize technology like the Delaware Valley Early Warning System, test for potential threats like Per- and poly-fluoroalkyl substances (PFAS), and partner with upstream organizations to monitor other possible concerns.

Though, we’re doing significant work today, we’re also planning for tomorrow…

The new 25-year Water Revitalization Plan will allow us to continue to provide safe and reliable drinking water for the next generation. The plan will ensure system-wide resiliency for a range of emergency conditions.

In light of recent PFAS regulations set by the EPA, we’re in the planning and piloting phases to upgrade treatment plants with top, cost-effective technologies to meet these federal regulations when they begin.

Additionally, we’re working to identify lead sources and remove lead from plumbing in properties across the city. Due to updated Federal and State regulations, PWD is piloting free tests of water samples at schools and childcare facilities.

For Philadelphia Water Department staff, this work spills beyond our professions. Every day, our employees drink the water we deliver to our customers.

We know the importance of clean tap water you can trust.

Sincerely,

Randy E. Hayman, Esq.
Water Commissioner

Belmont Drinking Water Treatment Plant

Queen Lane Drinking Water Treatment Plant

Baxter Drinking Water Treatment Plant

Water treatment operations began on these sites over 100 years ago. Many of the current buildings that comprise our treatment plants were built over 60 years ago, dating to the 1950s and 60s.

A PWD employee collects a water sample from the river.
Monitoring source water to promote health and safety

We study PFAS and other potentially harmful chemicals from industry in the region.

a photo divided into fairly even thirds, the bottom showing one of our rivers, trees across the middle, and sky in the top third.
Reducing emergency response times

The Delaware Valley Early Warning System is a web-based tool keeping our source waters safe.

a smiling staff member in a navy blue PWD t-shirt, zip-up hoodie, and matching winter cap stands in front of the doors to a drinking water treatment plant.
High-quality staff, high-quality results

The experts working at our treatment plants take pride in using water drawn from our local rivers. Hundreds of millions of gallons of top-quality drinking water are produced every day.

hands hold up a copy of PWD's Water Revitalization Plan
Redundancy from both rivers, a once-in-a-generation investment

The Water Revitalization Plan allows us to create a drinking water system that can respond to events like natural disasters or emergencies.

Table of Contents

Image of a two-story beige building with trees on either side and a large blue rectangle representing a reservoir full of water behind it
1: Source & Treatment

Philly’s local water sources and what we do to keep water safe

Image of a parking lot, a girl, two cars and a tree. Parking lot's surface is cut away to reveal water pipes underneath.
2: Delivery

Safe transit through the system

Image of a small apartment building and trees on a street. The wall of the house is cut away to show kitchen and basement sinks and water pipes under the street that lead to the house
3: At your taps

The final stretch to your tap

a blue magnifying glass, zooming in on a section of water quality data tables
2023 Data tables & more

Look for these quick guides throughout the report:

A Closer Look

a hypothetical example of a bar chart shows four light blue rectangles at different heights

Charts and graphs let you see the data in a new way.

Here’s the story of why we do this test

Handwritten notes explain how and why we do these tests.

☑RESULT:

All results are better than the recommended federal levels.

Look here for key takeaways.

Contact Information

Philadelphia Water Department
1101 Market St.
Philadelphia, PA 190107

Public Water System ID #PA1510001

Brian Rademaekers
Public Information Officer, Public Affairs
(215) 380-9327

Sharing this report

water.phila.gov/2023-quality

Cover page of PWD's 2023 Drinking Water Quality Report
View as PDF

Please share this report with all people who drink this water, especially those who may not have received this notice directly (for example, people in apartments, nursing homes, schools and businesses). You can do this by posting this notice in a public place or distributing copies by hand and mail.

To receive a printed copy of this report, please email: waterquality@phila.gov

People with special health concerns

Some people may be more vulnerable to contaminants in drinking water than the general population. Immunocompromised persons, such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS and other immune system disorders, and some elderly people and infants can be particularly at risk from infections.

These people should seek advice about drinking water from their health care providers.

U.S. Environmental Protection Agency (EPA)/Centers for Disease Control (CDC) guidelines on appropriate means to lessen the risk of drinking water contaminants are available from the Safe Drinking Water Hotline: (800) 426-4791.

1

Source & treatment

Your water begins in freshwater streams

Philadelphia’s water comes from the Delaware River Watershed. The watershed begins in New York State and extends 330 miles south to the mouth of the Delaware Bay. The Schuylkill River is part of the Delaware River Watershed.

Protection starts at the sources

We take a holistic approach, beginning with Philadelphia’s water supply. We monitor waterways across the watershed and look for potential sources of contamination. We keep track of water availability and flow.

Our wide range of tools for protecting water sources includes:

Research
  • We study regional influences, such as natural gas drilling, and global influences like sea level rise.
Projects in the field
  • We protect against stormwater and agricultural runoff.
  • We monitor water contaminants.
Partnerships
  • We team up with organizations across the region to protect our entire watershed.

Philadelphia source watersheds

   Delaware River Watershed

   Schuylkill River Watershed

A map showing the Delaware and Schuylkill River Watersheds, which supply Philadelphia's water. The map includes the entire eastern border of Pennsylvania, most of New Jersey, and a bit of Delaware and Maryland (which aren't labeled). The Delaware watershed covers and loosely follows that border,, extending farther west into PA than it does east into NJ. It includes Allentown, Reading, and Philadelphia, PA, Trenton New Jersey, and downstream of us, Wilmington, DE. Scranton is included on the map but is outside the watershed. The Schuylkill watershed is a subsection of the Delaware's, on the west side, extending from north and west of Reading southeast to Philadelphia, where the Schuylkill River joins the Delaware.

Monitoring source water to promote health and safety

We protect our rivers from threats and pollution sources locally and beyond the City limits.

Per- and polyfluoroalkyl substances (PFAS) are a family of industrial chemicals. There are more than 9,000 different types that have been used for decades in various products, such as frying pans and cosmetics. These substances do not break down easily or quickly, so they’re sometimes called “forever chemicals.”

Exposure over time to certain types of PFAS substances can have effects on human health.

Philadelphia’s drinking water meets all current state and federal regulations for PFAS – and we support all upcoming federal regulations.

We are already piloting ways to address upcoming, stricter regulations. PWD is planning to upgrade our drinking water treatment plants with the best technologies to protect our water quality.

A PWD employee stands in a shallow section of an upstream waterway, collecting a sample of water for testing.

Planning for today and tomorrow

⮝ Routine testing for PFAS

We collect samples upstream and within the city’s waterways. We also test the finished, treated water sent to homes and business across the City.

Small-scale labs ⮞

Inside a container about the size of a trailer, PWD scientists test the methods planned for upgraded treatment plants.

A PWD scientist wearing a white lab coat, safety goggles, and blue disposable gloves draws a sample from a tap on our "mini plant".

Spotlight:

Delaware Valley Early Warning System (EWS)

Reducing emergency response times by communicating across the area.

Our drinking water is a resource shared by millions of people in towns and cities across the region. The Delaware Valley Early Warning System (EWS) protects drinking water by providing rapid notifications to organizations and utilities like PWD.

The web-based emergency communication system reports events like truck and freight accidents and chemical spills that may impact our source water.

Drinking Water Treatment Plants

An important early step in water’s journey.

We have three drinking water treatment plants.

Baxter pulls water from the Delaware River. Queen Lane and Belmont pull from the Schuylkill.

Each plant has a service area. Some areas in Philadelphia can receive a mix from multiple treatment plants.

Use this map or enter your address to see where your water is treated:

a simplified map of Philadelphia shows the Schuylkill and Delaware rivers, with Market and Broad Streets indicated for reference. PWD's three drinking water treatment plants are displayed - Belmont on the northern edge of West Philly, Queen Lane on the other side of the Schuylkill in the northwest, and Baxter up in the Northeast by the Delaware. Areas of the city are shaded in different colors and patterns to indicate which plant(s) provide water to those sections - Belmont is the primary source for the part of Philadelphia west of the Schuylkill - most of that area also recieves a mix of water from the other plants, with only a strip in the northern part of West Philly being served exclusively by the Belmont plant. Queen Lane serves Northwest Philadelphia, and Baxter serves all of the North and Northeast. Those areas meet around north Broad Street, with sections around and slightly west of Broad, and much of Center City and all of South Philly receiving a mix of water from Queen Lane and Baxter.
key indicating what the colors/patterns of shading in the map mean (map's alt text provides a detailed description)

Note: This map reflects typical day‑to‑day operations.
Areas receiving a mix may be altered in emergency situations.

Typical Treatment Processes

These are some of the stages water goes through during normal operating conditions.

Before water leaves the plant

We test our treated water for about 100 regulated contaminants, ranging from organisms like bacteria to chemicals like nitrate.

In 2023, we found no violations under state and federal regulations.

a scientist with short salt and pepper hair and close cropped beard, wearing a white lab coat and black glasses is seen in profile, peering into a microscope with pencil in hand.

Final touches

Chlorine + Ammonia

Chlorine protects us from organisms found in untreated water that can cause disease. Ammonia is added to make the chlorine last longer and reduce the bleach-like smell.

Fluoride

All water contains some fluoride. We adjust the natural levels slightly to help protect your teeth against decay.

Zinc orthophosphate

Zinc orthophosphate is a compound that helps form a protective coating on pipes. It prevents corrosion (or breaking down over time).

A Closer Look

Turbidity

Turbidity is a measurement of cloudiness from particles. A high turbidity reading means there are a lot of particles in the water. They could be sand, silt, or organic particles.

We monitor turbidity because it is a good indicator of the effectiveness of our filtration system.

Good to know: Turbidity is different from the cloudiness you sometimes see when air bubbles are trapped in your tap water. Air bubbles usually disappear after a few minutes.

How we test for turbidity
To test for turbidity, a sample is placed between a light source and a detector. If the water is turbid, less light can penetrate through the sample to reach the detector. In clear water, more light is able to pass through to be detected on the other side.

In turbid water, light shines into water and bounces off particles.

In clear water, light passes directly through to the detector.

2023 Average Results
Turbidity is measured with an instrument called a nephelometer. Measurements are given in NTU (nephelometric turbidity units). A bold line at the top of the chart indicates we must keep 95% of samples at or below 0.300 NTU. Dots for the three Drinking Water Treatment Plants are all well below that - Belmont is indicated a bit below 0.050 NTU, Queen Lane even lower around 0.025 NTU, and Baxter a touch over the 0.050 NTU line.
What this means for you

Why can high turbidity lead to a drinking water warning?
Turbidity itself has no health effects. However, it can interfere with disinfection. If we can’t measure turbidity during disinfection, we can’t be sure the process has worked properly.

☑Result:

Our water samples are consistently less turbid than limits set by the EPA.

2

Delivery

A safe path through the system

We have about 3,100 miles of water mains that deliver clean tap to customers. To ensure water stays safe as it moves from the plant to you, we take samples and monitor real-time water quality data, 24/7.

photo of a man filling a glass bottle from a monitoring tap in a utility box mounted on a cinderblock wall.

A Closer Look

Residual Chlorine

This test is done throughout the system. It checks that the chlorine added at plants remains at levels that keep water fresh and safe while staying within regulations.

Most recent results
A chart showing the range of acceptable levels of Residual Chlorine in parts per million (ppm). The lowest level allowed is indicated at 0.2 ppm, while the highest level allowed is indicated at 4.0 ppm. PWD's monthly average is shown to be right in the middle, indicated as a range shaded with diagonal lines from a just below 2.0 to a little above 2.5 ppm. (Exact range is 1.93-2.60ppm)
What this means for you

We travel the city to collect samples of drinking water from fire and police stations, pumping stations, and more.

We do over 400 of these tests every month!

☑Result:

Better than standards.

Spotlight:
Water Revitalization Plan

Upgrading our infrastructure

The Water Revitalization Plan (WRP) is our 25-year plan to strengthen essential drinking water infrastructure.

What will revitalization mean for Philadelphians?

It means improving water infrastructure: the pipes, treatment plants, facilities, and processes we rely on for safe water in every neighborhood.

We need to do this work now to be ready for the changes facing our city, including more severe storms and an aging system.

An ambitious approach

The Water Revitalization Plan identified approximately 400 projects focused on the improvement of existing facilities and the construction of several new facilities.

Key projects include:
  • Schuylkill River Crossing (Transmission piping)
  • Baxter Drinking Water Treatment Plant Upgrade
  • Belmont Drinking Water Treatment Plant Upgrade
  • Queen Lane Drinking Water Treatment Plant Upgrade
a very simple timeline shows three phases - "Feasibility" ends at 2023, where "Planning" begins. There is a "We are here" marker above that transition. The Planning phase continues until 2025, where the final, longest phase begins, labeled "Initial Construction for early key projects"

Why are we doing this now?

The City is facing a challenge similar to other large cities across the country: the need to update aging infrastructure.

The facilities you rely on for safe water are in need of major upgrades. Without these improvements, we’ll likely experience more unplanned repairs, which could be costly and disruptive for residents.

Tapping into the community

The WRP Stakeholder Advisory Group is comprised of community members with a vested interest in projects related to the WRP.

PWD is hosting regular community listening sessions both virtually and in-person around the city to inform Philadelphians about the plan.

Sign up to receive project news & learn how you can get involved.

⮞ water.phila.gov​/revitalization

3

At your taps

Water where you live, work, and play

When water leaves a water main, it enters a property’s service line. From there, the property’s plumbing system carries water to the taps or fixtures we use every day at home, school, or work.

A child, visible only from the waist and elbows down, wearing a black jacket and leggings with white lace-up boots with black laces, is sitting on some outdoor stairs with brick risers and stone slab treads. Her legs are crossed at the ankles, two steps below the one she's seated on, and her hands are folded on her knee. A reusable water bottle with the PWD logo and a black basket ball rest on the step above her feet. Another child's feet (in brown pants and white Chuck Taylor sneakers), water bottle, and pink backpack can be seen in the top right corner as well.

1 in 3

Approximate number of customers who don’t trust the pipes in their home.

Our most recent annual Customer Survey shows 37% of customers don’t trust their pipes at home. Flushing (see the next section) is an excellent way to trust your tap water!

Source: 2023 Comprehensive Survey Report

We hear you!

Thanks to customer surveys and neighborhood events like the Philly Water Bar, we hear loud and clear from the people of Philadelphia:

Safe drinking water is a top priority for our customers.

Patrons visiting the popup Philly Water Bar in the City Hall courtyard.

Does your tap water appear cloudy?

This is usually not a water quality issue. Water pressure in the main creates air bubbles in water. When you fill a glass with tap water, the bubbles rise from the bottom of the glass and are released at the top.

Call us to report a water quality issue if the bubbles don’t disappear after a few seconds.

Meet your service line

The service line is the pipe that carries clean water into your property from the city’s network of water mains.

a cutaway diagram showing the basement of a home and the pipes underground outside it. a larger pipe running under the street is labeled "City's water main" and a pipe running from the main into the basement of the home to the water meter is labeled "Your service line". This pipe is divided by a vertical column coming up to the curb stop. The section of the service line between the main and the curb stop is called the "service side" and the section between the curb stop and the house is called the "supply side".

The service line is a part of your property’s plumbing, even though it’s underground.

If you own your property, the service line is your responsibility.

Flush your pipes

Run fast, cold water from a faucet for 3–5 minutes. This will flush out water that’s been sitting in your pipes.

When to flush pipes: If you haven’t used water for 6 hours or more— usually first thing in the morning when you wake up or when you come home after work or school.

If your property has a lead service line: Flushing is important to do every day.

Cost: It costs only pennies (or less) per day!

How it works

Flushing pushes the water that is sitting in pipes out and down your drain until fresh water comes through the tap.

Fresh water starts at
our water mains.

diagram shows a section of water main with an arrow labeled "start" pointing away from it, along a customer's service line. The pipe enters the basement, where the water meter is, and then another section of pipe carries it to the rest of the house. A second arrow points upward to the first fixture it reaches where water can be run, to flush the pipes, typically a basement utility sink or bathtub or sink with aerator removed on the lowest level with a bathroom.

Running the tap gets rid of water sitting in pipes.

If lead is found in water, the source is somewhere in a property’s plumbing

a sink
In a home’s older fixtures & valves:

Lead can also be in solder where pipes are joined.

a small section of a property's service line is visible between the exterior wall (usually at the front of the property) and the building's water meter.
In a part of a service line:

This is one of the first places to look for lead.

cutaway diagram of a small brick home typical of Philadelphia row houses, showing the service line bringing fresh water from the water main under the street, into the basement of the home, where the water meter is located, and then pipes carry the water to fixtures in the home.
Age matters

Older fixtures and buildings are more likely to contain lead. Lead was used less after the 1950s, but fixtures and solder could still contain lead. Brass fixtures could contain lead until as late as 2014.

The good news?
We use Corrosion Control.

Zinc Orthophosphate, added during treatment, forms a protective coating on the inside of pipes.

For over 25 years, Philadelphia has successfully used this process to reduce the amount of lead that can dissolve from plumbing into water. However, different building plumbing systems and usage patterns can affect how well corrosion control works.

illustration of a pipe with very little buildup on the inside, so water can flow through it easily and remain clean and clear
With corrosion control
pipe shown with corrosion and residue built up on the inside, impeding the flow, and particles that have broken loose are visible in the water.
Without corrosion control

How do we know it works?
Tests at homes with lead plumbing show our treatment is working: corrosion control keeps lead levels below state and federal limits.

1 in 20

Estimated households with lead service lines in Philadelphia.

We have gathered a variety of sources for recent estimates, but this number is only an estimate. Further verification is needed.

Source: PWD Data

Sharing a map of service line materials for properties in Philadelphia.

We’re using data on service line materials collected during meter upgrade appointments. However, no materials identification method is 100% accurate. Further testing may be required to confirm the materials of the entire length of a service line.

IT’S THE LAW: We’re required by regulations to offer this information to the public.

a worker in blue shirt and overalls, yellow hard hat, reflective vest, and work gloves, is seen from the hips upward while digging a hole in the sidewalk in front of a brick building. The bottom of the front steps and an orange cone are visible in the background..

We offer a zero-interest loan for replacing lead service lines.

The Homeowners Emergency Loan Program (HELP) can cover the cost of a replacement.

⮞ Learn more & apply: www.phila.gov​/water/helploan

Two scientists, wearing white lab coats and safety glasses, at work in one of our labs. The one on the left is sitting at a lab table, using a computer. The one on the right is standing at another lab table, wearing blue disposable gloves, examining a water sample collection bottle, with several others lined up on the table. Various machines and a window are visible in the background.

Scientists in our labs analyze water samples collected in homes throughout Philadelphia.

A Closer Look

Carefully Monitoring Lead

In addition to regular tests in customer homes, we also perform rounds of sampling for lead and copper regulations.

We share the results with the EPA and the public.

The Environmental Protection Agency (EPA) requires that 90% of homes show lead levels less than 15 ppb.

Most recent results
lead levels plotted on a chart with a vertical scale of 0 to 16 parts per billion, with lines at 2 ppb intervals. The highest level allowed is indicated at 15 ppb. Results from 2016 are plotted with a dot between the 2 and 4 ppb lines, closer to 2. The 2017 indicator is just above 2 ppb. 2019 is marked slightly higher, about the same as 2016, and the 2022 indicator is back down to about 2 ppb. A note to the right says "The last 4 rounds of testing show levels well below limits." Below the chart, it says "For each round: We take samples from 50-100 homes that have lead service lines."
What this means for you

New guidelines will require more sampling and stricter limits. PWD expects to meet new requirements. We’re increasing our efforts to help keep lead out of drinking water.

☑Result:

Lead levels are consistently lower than limits set by the EPA.

US EPA Guidance

The EPA requires public water providers like the Philadelphia Water Department to monitor drinking water for lead at customer taps. If lead levels are higher than 15 parts per billion (ppb) in more than 10% of taps sampled, water providers must inform customers and take steps to reduce lead in water.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from material and components associated with service lines and home plumbing.

The Philadelphia Water Department is responsible for providing safe drinking water but cannot control the variety of materials used in plumbing components. If you haven’t turned on your tap for several hours, you can minimize the potential for lead exposure by flushing your tap before using water for drinking and cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline (800) 426-4791 or at: www.epa.gov/safewater/lead.

+

2023 Data tables & more

An introduction to the results

All of PWD’s results are better than the required and recommended federal levels designed to protect public health.

This data shows how our process keeps your drinking water safe.

By reporting these results in these tables, we are meeting a requirement of the EPA.

Some contaminants may pose a health risk at certain levels to people with special health concerns. Others are used as indicators for treatment plant performance.

PPM vs. PPB vs. PPT

Many of these results are reported as “parts per million (ppm)” or “parts per billion (ppb)”.

ppm (parts per million):
Denotes 1 part per 1,000,000 parts, which is equivalent to two-thirds of a gallon in an Olympic-sized swimming pool.

ppb (parts per billion):
Denotes 1 part per 1,000,000,000 parts, which is equivalent to half a teaspoon in an Olympic-sized swimming pool.

ppt (parts per trillion):
Denotes 1 part per 1,000,000,000,000 parts, which is equivalent to one drop in 20 Olympic-sized swimming pools.

Illustration: GoodStudio / Shutterstock.com, and Philadelphia Water Department

Glossary

Here are definitions for some words and phrases we use in the report and in our data tables.

  • Action Level: The concentration of a contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow. The action level is not based on one sample; instead, it is based on many samples.
  • Alkalinity: A measure of the water’s ability to resist changes in the pH level and a good indicator of overall water quality. Although there is no health risk from alkalinity, we monitor it to check our treatment processes.
  • E. coli (Escherichia coli): A type of coliform bacteria that is associated with human and animal fecal waste.
  • gpg (grains per gallon): A unit of water hardness. One grain per gallon is equal to 17.1 parts per million.
  • MCL (Maximum Contaminant Level): The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment technology.
  • MCLG (Maximum Contaminant Level Goal): The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.
  • mg/L (Milligrams per liter): One milligram per liter is equal to one part per million.
  • MRDL (Maximum Residual Disinfection Level): The highest level of disinfectant that is allowed in drinking water. The addition of a disinfectant is necessary for the control of microbial contaminants.
  • MRDLG (Maximum Residual Disinfection Level Goal): The level of a disinfectant in drinking water below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.
  • Minimum Residual Disinfectant Level: The minimum level of residual disinfectant required at the entry point to the distribution system.
  • NTU (nephelometric turbidity units): Turbidity is measured with an instrument called a nephelometer. Measurements are given in nephelometric turbidity units.
  • Pathogens: Bacteria, virus, or other microorganisms that can cause disease.
  • pCi/L (Picocuries per liter): A measure of radioactivity.
  • ppm (parts per million): Denotes 1 part per 1,000,000 parts, which is equivalent to two thirds of a gallon in an Olympic-sized swimming pool.
  • ppb (parts per billion): Denotes 1 part per 1,000,000,000 parts, which is equivalent to half a teaspoon in an Olympic-sized swimming pool.
  • ppt (parts per trillion): Denotes 1 part per 1,000,000,000,000 parts, which is equivalent to one drop in 20 Olympic-sized swimming pools.
  • Service Line: The pipe that brings water from the water main into your home or business.
  • SMCL (Secondary Maximum Contaminant Level): Non-enforcable Federal water quality guidelines that are established for managing aesthetic and cosmetic conditions of water (e.g. taste, odor, color).
  • SOC (Synthetic Organic Chemical): Commercially made organic compounds, such as pesticides and herbicides.
  • Total Coliform: Coliforms are bacteria that are naturally present in the environment. Their presence in drinking water may indicate that other potentially harmful bacteria are also present.
  • THAAs (Total Haloacetic Acids): A group of chemicals known as disinfection byproducts. These form when a disinfectant reacts with naturally occurring organic and inorganic matter in the water.
  • TOC (Total Organic Carbon): A measure of the carbon content of organic matter. This measure is used to indicate the amount of organic material in the water that could potentially react with a disinfectant to form disinfection byproducts.
  • TTHMs (Total Trihalomethanes): A group of chemicals known as disinfection byproducts. These form when a disinfectant reacts with naturally occurring organic and inorganic matter in the water.
  • Treatment Technique: A required process intended to reduce the level of a contaminant in drinking water.
  • Turbidity: A measure of the clarity of water related to its particle content. Turbidity serves as an indicator for the effectiveness of the water treatment process. Low turbidity measurements, such as ours, show the significant removal of particles that are much smaller than can be seen by the naked eye.
  • VOC (Volatile Organic Chemicals): Organic chemicals that can be either man-made or naturally occurring. These include gases and volatile liquids.
  • WTP: Water Treatment Plant
  • μg/L (Microgram per liter): One microgram per liter is equal to one part per billion.

What we test for and how

Public drinking water systems monitor their treated drinking water for approximately 100 regulated contaminants. These regulatory parameters are defined within federal rules, such as the Revised Total Coliform Rule, Surface Water Treatment Rule, Disinfectants and Disinfection Byproducts Rules, Lead and Copper Rule, and the Radionuclides Rule.

We monitor for the regulated parameters listed below.

Any contaminants found are noted in the tables on the following pages.

Inorganic Chemicals
  • Antimony
  • Arsenic
  • Barium
  • Beryllium
  • Cadmium
  • Chromium
  • Copper
  • Cyanide
  • Fluoride
  • Lead
  • Mercury
  • Nickel
  • Nitrate
  • Nitrite
  • Selenium
  • Thallium
Synthetic Organic Chemicals
  • 2,3,7,8 – TCDD (Dioxin)
  • 2,4 – D, 2,4,5 – TP (Silvex)
  • Alachlor
  • Atrazine
  • Benzopyrene
  • Carbofuran
  • Chlordane
  • Dalapon
  • Di(ethylhexyl) adipate
  • Di(ethylhexyl) phthalate
  • Dibromo­chlo­ro­pro­­pane
  • Dinoseb
  • Diquat
  • Endothall
  • Endrin
  • Ethylene Dibromide
  • Glyphosate
  • Heptachlor
  • Heptachlor epoxide
  • Hexachlo­ro­ben­zene
  • Hexachlo­ro­cyc­lo­­penta­diene
  • Lindane
  • Methoxychlor
  • Oxamyl
  • PCBs Total
  • Penta­chlo­ro­­phe­­nol
  • Picloram
  • Simazine
  • Toxaphene
Volatile Organic Chemicals
  • Benzene
  • Carbon Tetrachlo­ride
  • 1,2-Dichlo­ro­­e­thane
  • o-Dichlo­ro­ben­­zene
  • p-Dichlo­ro­ben­­zene
  • 1,1-Dichlo­ro­­eth­y­lene
  • cis-1,2-Dichlo­ro­eth­y­lene
  • trans-1,2-Dichlo­ro­­eth­y­lene
  • Dichloro­me­thane
  • 1,2-Dichloro­pro­pane
  • Ethylben­zene
  • Mono­chlo­ro­ben­zene
  • Styrene
  • Tetrachlo­ro­eth­­y­lene
  • Toluene
  • 1,2,4-Trichlo­­ro­ben­­zene
  • 1,11-Trichlo­­ro­­ethane
  • 1,1,2-Trichlo­ro­­ethane
  • Trichloro­eth­y­lene
  • o-Xylene
  • m,p-Xylenes
  • Vinyl Chloride
Radiological Contaminants
  • Uranium
  • Alpha Emitters
  • Radium 226
  • Radium 228

Other factors that can impact drinking water

Appealing to Your Senses

We work to ensure your water looks, tastes and smells the way it should.

To meet all water quality taste and odor guidelines, we test for the following: alkalinity, aluminum, chloride, color, hardness, iron, manganese, odor, pH, silver, sodium, sulfate, surfactants, total dissolved solids, turbidity, and zinc.

Temperature and Cloudiness

The temperature of the Schuylkill and Delaware Rivers varied seasonally in 2023 from approximately 37°–90° Fahrenheit. PWD does not treat the water for temperature.

Cloudiness in tap water most commonly happens in the winter, when the cold water from the water main is warmed up quickly in household plumbing. Cold water and water under pressure can hold more air than warmer water and water open to the atmosphere.

When really cold winter water comes out of your tap, it’s simultaneously warming up and being relieved of the pressure it was under inside the water main and in your plumbing. The milky white color is actually just tiny air bubbles. If you allow the glass to sit undisturbed for a few minutes, you will see it clear up gradually.

2023 Data tables

Lead & Copper
– Tested at customers’ taps: Testing is done every 3 years. Most recent tests were done in 2022.
EPA’s Action Level – for a representative sampling of customer homesIdeal Goal (EPA’s MCLG)90% of PWD customers’ homes were less thanNumber of homes considered to have elevated levelsViolationSource
Lead90% of homes must test less than 15 ppb0 ppb2.0 ppb3 out of 104NoCorrosion of household plumbing;
Erosion of natural deposits
Copper90% of homes must test less than 1.3 ppm1.3 ppm0.219 ppm0 out of 104NoCorrosion of household plumbing; Erosion of natural deposits; Leaching from wood preservatives
Inorganic Chemicals (IOC)
– PWD monitors for IOC more often than required by EPA.
ChemicalHighest Level Allowed (EPA’s MCL)Ideal Goal (EPA’s MCLG)Highest resultRange of Test Results for the YearViolationSource
Barium2 ppm2 ppm0.047 ppm0.024–0.047 ppmNoDischarges of drilling wastes; Discharge from metal refineries; Erosion of natural deposits
Chromium100 ppb100 ppb2 ppb0–2 ppbNoDischarge from steel and pulp mills; Erosion of natural deposits
Fluoride2 ppm*2 ppm*0.83 ppm0.66–0.83 ppmNoErosion of natural deposits; Water additive which promotes strong teeth; Discharge from fertilizer and aluminum factories
Nitrate10 ppm10 ppm3.82 ppm0.69–3.82 ppmNoRunoff from fertilizer use; Leaching from septic tanks; Erosion of natural deposits
  • * EPA’s MCL and MCLG is 4 ppm, but PADEP has set this lower MCL and MCLG which takes precedence.
Radiological Contaminants
Highest Level Allowed (EPA’s MCL)Ideal Goal (EPA’s MCLG)Highest resultRange of Test Results for the YearViolationSource
Alpha Emitters15 pCi/L0 pCi/L5.32 pCi/L0–5.32 pCi/LNoErosion of natural deposits
Total Chlorine Residual
– Continuously monitored at Water Treatment Plants
Sample LocationMinimum Disinfectant Residual Level AllowedLowest Level DetectedYearly RangeViolationSource
Baxter WTP0.2 ppm2.30 ppm2.30–3.40 ppmNoWater additive used to control microbes
Belmont WTP1.86 ppm1.86–2.71 ppm
Queen Lane WTP1.97 ppm1.97–3.53 ppm
Total Chlorine Residual
– Tested throughout the Distribution System.
Over 360 samples collected throughout the City every month.
Sample LocationMaximum Disinfectant Residual AllowedHighest Monthly AverageMonthly Average RangeViolationSource
Distribution System4.0 ppm2.60 ppm1.93–2.60 ppmNoWater additive used to control microbes
Bacteria in Tap Water
– Tested throughout the Distribution System.
Over 400 samples collected throughout the City every month.
Highest Level Allowed (EPA’s MCL)Ideal Goal (EPA’s MCLG)Highest Monthly % or Yearly Total of Positive SamplesMonthly Range (% of Samples)ViolationSource
Total ColiformNo more than 5% of samples can test positive in a single month*00.6%0%–0.6%NoNaturally present in the environment
E. coli00%0%NoHuman or animal fecal waste.
  • * Every sample that is positive for total coliforms must also be analyzed for E. coli. If a system has two consecutive total coliform positive samples, and one is also positive for E. coli, then the system has an MCL violation. There were no Level 1 or Level 2 assessments required under the Revised Total Coliform Rule in 2023.
Total Organic Carbon
– Tested at Water Treatment Plants
Treatment Technique RequirementBaxter WTP One Year AverageBelmont WTP One Year AverageQueen Lane WTP One Year AverageViolationSource
Percent of Removal Required25–45%25–45%25–45%n/aNaturally present in the environment
Percent of Removal Achieved*17–72%20–74%33–71%No
Number of Quarters out of Compliance*000
  • * PWD achieved TOC removal requirements in all quarters of 2022 at all WTPs. Compliance is based on a running annual average computed quarterly. The numbers shown represent a range of TOC results in weekly samples.
Turbidity, a measure of clarity
– Tested at Water Treatment Plants
Baxter WTP One Year AverageBelmont WTP One Year AverageQueen Lane WTP One Year AverageViolationSource
Treatment Technique Requirement: 95% of samples must be at or below 0.300 NTU100% below 0.300 NTU100% below 0.300 NTU100% below 0.300 NTUn/aSoil runoff, river sediment
Highest single value for the year0.099 NTU0.180 NTU0.153 NTUNo
Yearly Average0.058 NTU0.049 NTU0.028 NTU

We are required to monitor your drinking water for specific contaminants on a regular basis. The results of this monitoring indicate whether or not your drinking water meets health standards. PWD continuously operates and monitors water quality from a total of 160 filters at three drinking water treatment plants. In calendar year 2023, on one occasion, continuous on-line turbidity monitoring was interrupted on one of our filters and therefore we cannot be sure of the quality of the drinking water from this filter during the interruption. On June 4th, 2023, Filter #2 at the Queen Lane Plant was found in service without turbidity monitoring for a period of 62.5 hours. The monitoring interruption was a result of a software upgrade on the turbidimeter controller that left the turbidimeter in hold mode, creating an artificial steady turbidity reading, until operators recognized the data trend was not responding on June 4th, 2023. During this single filter monitoring interruption, the combination flow from the plant filters at Queen Lane Plant was continuously sampled and monitored with no change in turbidity levels. The software upgrade issue on the turbidimeter controller was later resolved by the manufacturer. No water quality emergency occurred due to the monitoring interruption, and this notice is for informational purposes only.

Disinfection Byproducts
Highest Level Allowed (EPA’s MCL) – One Year AverageRunning Annual Average 2023*System Wide Range of ResulstsViolationSource
Total Trihalomethanes (TTHMs)80 ppb52 ppb17–91ppbNoByproduct of drinking water disinfection
Total Haloacetic Acids (THAAs)60 ppb42 ppb16–63 ppbNoByproduct of drinking water disinfection
  • * Monitoring is conducted at 16 locations throughout the City of Philadelphia.
    This result is the highest locational running annual average in 2023.
Unregulated Contaminant Monitoring (UCMR)1
ChemicalTesting PeriodAverageRange
Bromide21/14/20200.034 ppm0–0.052 ppm
Total Organic Carbon (TOC)1/14/20202.27 ppm2.19–2.34 ppm
HAA5 Total31/14/202021.3 ppb14.8–31.3 ppb
HAA6BR Total41/14/20207.1 ppb3.8–10.3 ppb
HAA9 Total1/14/202028.2 ppb23.6–35.5 ppb
Manganese1/15/20200.55 ppb0–0.95 ppb
  • 1 Unless otherwise noted, samples were collected from finished water sampling locations.
  • 2 Bromide and TOC represent source water samples.
  • 3 HAA5 Total – Dibromoacetic Acid, Dichloroacetic Acid, Monobromoacetic Acid, Monochloroacetic Acid, and Trichloroacetic Acid
  • 4 HAA6Br Total – Bromochloroacetic Acid, Bromodichloroacetic Acid, Dibromoacetic Acid, Dibromochloroacetic Acid, Monobromoacetic Acid, and Tribromoacetic Acid
  • 5 HAA9 Total – Bromochloroacetic Acid, Bromodichloroacetic Acid, Chlorodibromoacetic Acid, Dibromoacetic Acid, Dichloroacetic Acid, Monobromoacetic Acid, Monochloroacetic Acid, Tribromoacetic Acid, and Trichloroacetic Acid

In 2020, PWD performed special monitoring as part of the Unregulated Contaminant Monitoring Rule (UCMR), a nationwide monitoring effort conducted by the EPA. Unregulated contaminants are those that do not yet have a drinking water standard set by the EPA. The purpose of monitoring for these contaminants is to help the EPA decide whether the contaminants should have a standard. For more information concerning UCMR, visit these websites: https://www.epa.gov/dwucmr/fourth-unregulated-contaminant-monitoring-rule or https://drinktap.org/Water-Info/Whats-in-My-Water/Unregulated-Contaminant-Monitoring-Rule-UCMR

Unregulated contaminants not detected at any of the sampling locations:
1-Butanol, 2-Methoxyethanol, 2-Propen-1-ol, alpha-Hexachlorocyclohexane, anatoxin-a, Butylated Hydroxyanisole, Chlorpyrifos, Cylindrospermopsin, Dimethipin, Ethoprop, Germanium, Microcystin Total, Nodularin, o-Toluidine, Oxyfluorfen, Permethrin Total, Profenofos, Quinoline, Tebuconazole, Tribufos

Secondary Chemicals

EPA has established National Secondary Drinking Water Regulations (NSDWRs) that set non-mandatory water quality standards. EPA does not enforce these “secondary maximum contaminant levels” (SMCLs). They are established as guidelines to assist public water systems in managing their drinking water for aesthetic considerations, such as taste, color, and odor. These contaminants are not considered to present a risk to human health at the SMCL.

Secondary MCLs: Aesthetic Impacts in Tap Water
ChemicalEPA’s SMCLBaxter WTP One Year RangeBelmont WTP One Year RangeQueen Lane WTP One Year RangeViolation*Source
Chloride250 ppm53–66 ppm58–109 ppm54–115 ppmNoMain component of many salts, may increase in winter months; Erosion of natural minerals; Used in the water treatment process in the form of ferric chloride.
Copper1.0 ppm0.098–0.218 ppm0.004–0.026 ppm0.022–0.037 ppmNoCorrosion of coper pipes in premise plumbing; Erosion of natural deposits.
Fluoride2 ppm**0.66 ppm0.83 ppm0.73 ppmNoErosion of natural deposits; Water additive that promotes strong teeth; Discharge from fertilizer and aluminum factories.
Iron0.3 ppm0 ppm0–0.012 ppm0–0.010 ppmNoCorrosion of iron water mains and premise plumbing; Erosion of natural minerals; Used in the water treatment process in the form of ferric chloride.
pH6.5-8.57.05–7.257.1–7.37.08–7.24NoAdjusted during the water treatment process.
Sulfate250 ppm8.32–28.9 ppm20.30–55.40 ppm10.90–89.90 ppmNoErosion of natural minerals; Runoff from mining operations.
Total Dissolved Solids500 ppm128–242 ppm200–374 ppm194–396 ppmNoErosion of natural minerals; May increase during winter months due to road salt runoff or during drought conditions.

PWD also monitored for Aluminum, Color, Manganese, and Silver in 2022; all results were below respective parameter detection limits.

  • * Individual results are averaged monthly and compliance is based on running annual average.
  • ** EPA’s MCL and MCLG is 4 ppm, but PADEP has set this lower MCL and MCLG which takes precedence.
Sources of Secondary Chemicals
ChlorideMain component of many salts, may increase in winter months; Erosion of natural minerals; Used in the water treatment process in the form of ferric chloride.
CopperCorrosion of coper pipes in premise plumbing; Erosion of natural deposits.
FluorideErosion of natural deposits; Water additive that promotes strong teeth; Discharge from fertilizer and aluminum factories.
IronCorrosion of iron water mains and premise plumbing; Erosion of natural minerals; Used in the water treatment process in the form of ferric chloride.
pHAdjusted during the water treatment process.
SulfateErosion of natural minerals; Runoff from mining operations.
Total Dissolved SolidsErosion of natural minerals; May increase during winter months due to road salt runoff or during drought conditions.

Sodium, Hardness, and Alkalinity in tap water

The parameters listed below are not part of EPA’s requirements and are provided for information purposes.

Sodium in Tap Water
Baxter WTP One Year AverageBelmont WTP One Year AverageQueen Lane WTP One Year Average
Average (ppm)21 ppm42 ppm34 ppm
Average (mg in 8 oz. glass of water)5 mg10 mg8 mg
Range (ppm)16–26 ppm29–55 ppm19–46 ppm
Range (mg in 8 oz. glass of water)4–6 mg7–13 mg5–11 mg
Hardness in Tap Water
Baxter WTP One Year AverageBelmont WTP One Year AverageQueen Lane WTP One Year Average
Average90 ppm or 5 gpg136 ppm or 8 gpg154 ppm or 9 gpg
Minimum78 ppm or 5 gpg109 ppm or 6 gpg82 ppm or 5 gpg
Maximum105 ppm or 6 gpg180 ppm or 11 gpg206 ppm or 12 gpg
Hardness defines the quantity of minerals, such as calcium and magnesium, in water. These minerals react with soap to form insoluble precipitates and can affect common household chores such as cooking and washing. Philadelphia’s water is considered “moderately hard” or “hard” depending on your service area.
Alkalinity in Tap Water
Baxter WTP One Year AverageBelmont WTP One Year AverageQueen Lane WTP One Year Average
Average38 ppm70 ppm68 ppm
Minimum26 ppm52 ppm33 ppm
Maximum50 ppm88 ppm94 ppm

Top Customer Questions

How do I get my water tested?

We offer free lead and copper tests for residential customers who have concerns about their water.

To request an appointment Call (215) 685-6300

Why do water utilities add fluoride to water?

It’s a natural element that helps prevent cavities. Philadelphia’s Health Department (and dentists) recommend that we add fluoride to a level that helps protect children’s teeth.

water.phila.gov/drinking-water/FAQ

How hard is Philadelphia’s water?

Philadelphia’s water is considered moderately hard. Hardness depends on the treatment plant that serves your area of the city.

See results in the Hardness data table

Can I replace a lead service line?

Yes. If you don’t want to contact a plumber directly, apply for our Homeowners Emergency Loan Program (HELP).

A zero-interest loan can cover the cost of replacement.

Learn more & apply water.phila.gov/help

Also: PWD will replace lead service lines for free if they are discovered during planned work on water mains.

water.phila.gov/lead

Why does water have an earthy flavor sometimes?

Earthy or musty flavors occur naturally in drinking water and are among the most commonly reported worldwide. When certain algae-type organisms grow in our rivers, detectable levels of these odors can make their way into the treated drinking water.

These natural compounds have no known health effects at their natural levels, and are found in various foods.

We take steps to reduce their presence when detected.

water.phila.gov/drinking-water/FAQ

Why does my tap water smell like a pool sometimes?

The smell of chlorine means your water is safe and treated to remove harmful organisms. You can reduce the smell by keeping a pitcher of fresh water in the refrigerator. This also reduces the earthy odor sometimes produced by algae in the rivers during spring.

water.phila.gov/drinking-water/FAQ

Why does my water look cloudy sometimes?

This is usually not a water quality issue. Water pressure in the main creates air bubbles in water. When you fill a glass with tap water, the bubbles rise from the bottom of the glass and are released at the top.

Call us to report a water quality issue if the bubbles don’t disappear after a few seconds.

Call (215) 685-6300

Should I use a filter?

The water we deliver to your property does not need a filter. Your plumbing can impact your water quality, especially when service lines are disturbed. This can happen during construction or repairs near your property. If you use a filter, you must follow all instructions from the manufacturer. It should be certified for lead reduction by the National Sanitation Foundation (NSF).

Learn more at nsf.org

Working together

You can help protect Philadelphia’s water quality.

Two are at the bottom of the hill using shovels to excavate an overturned shopping cart partially buried in the silt at the edge of a creek, under the arc of a concrete bridge. A third, holding a pair of work gloves in one hand while bracing against the bridge with the other, carefully steps down the hill to join them.

Join a cleanup.

Group cleanups help remove trash and litter from our waterways. There are a number of ways to stay informed about upcoming cleanups: visit the @PhillyH2O blog (water.phila.gov/blog), follow us on social media (@phillyh2o), email us at waterinfo@phila.gov, or call us at (215) 685-6300.

Keep trash out of our waterways.

Make sure to put your recyclable paper, metal, and plastics in a recycling bin. Put disposable gloves, masks, food waste, and other garbage in a trash can, so they don’t end up in our rivers and streams.

A group on a GSI tour, as seen from the back of the pack, walks along a path surrounded by trees and greenery.

Take a tour.

Tour a water treatment plant to learn more about how we test and treat our water, or visit Green Stormwater Infrastructure (GSI) sites to learn how Philadelphia is using GSI to keep our water cleaner and make our city greener. To schedule a tour, email waterinfo@phila.gov.

Always properly recycle or dispose of household hazardous wastes.

Don’t flush them down the toilet or down the sink, and don’t pour them into storm drains. Many storm drains flow directly to our streams and rivers.

a view of the Fairmount Water Works and the Schuylkill river as the sun begins to set, glistening on the water and casting a golden glow over the historic buildings.

Visit the Fairmount Water Works Interpretive Center.

The Fairmount Water Works Interpretive Center is a great resource for educational programming and information. Topics include our water infrastructure and watersheds, local native wildlife, and STEAM (science, technology, engineering, arts, and math) activities. fairmountwaterworks.org

Don’t flush anything but toilet paper.

Yes, even “flushable” wipes! They don’t dissolve like toilet paper and can lead to clogs and backups, causing waste to flow into our homes and our streets.

Close up shot of a Philly Water Bar "bartender" pouring fresh cold Philly Tap Water from a clear plastic pitcher bearing the PWD logo and frosted with cold into a paper cone a visitor holds out. A stack of paper drinking cones, a colorful wheel visitors can spin, and the bartenders' bright teal t-shirts and royal blue aprons fill the background.

Enjoy top-quality tap at the Philly Water Bar.

The Philly Water Bar is a relationship-building tool and interactive platform that educates and engages the public around Philadelphia’s top-quality tap water. water.phila.gov/water-bar

Stay informed

Sign up to receive water quality updates and more!

Get the latest news, useful information, and find out about upcoming events.

water.phila.gov/signup

An illustration of cell phone with an envelope icon on the screen, next to a larger envelope with icons spilling out of it - an alert symbol, a glass of water, a droplet (that matches the ones used to mark treatment plans on the map), and a partial zip code (with the last digits obscured by the envelope so it could be anywhere in Philadelphia)
Organizations we partner with
  • American Water Resources Association
  • American Water Works Association
  • Partnership for Safe Water
  • American Public Works Association
  • Association of Metropolitan Water Agencies
  • National Association of Clean Water Agencies
  • Partnership for the Delaware Estuary
  • Schuylkill Action Network
  • Schuylkill River Restoration Fund
  • Tookany/Tacony-Frankford (TTF) Watershed Partnership
  • U.S. Water Alliance
  • Water Environment Federation
  • Water Environment Research Foundation
  • Water Research Foundation
     
City of Philadelphia & Philadelphia Water Department
Philadelphia Water Department

1101 Market Street
Philadelphia, PA 19107
(215) 685-6300
water.phila.gov

Photography
Sahar Coston-Hardy, Philadelphia Water Department, Veracity Studios
© Philadelphia Water Department