Philadelphia – Pennsylvania
Philadelphia, the nation’s sixth-largest city, serves approximately 2.2 million residents with water through the Philadelphia Water Department (PWD). With a water distribution system dating back to 1801, the city’s infrastructure includes over 3,000 miles of water mains, three water treatment plants, and 13 pumping stations, delivering roughly 300 million gallons daily.
The Delaware and Schuylkill rivers provide Philadelphia’s water supply, both protected by extensive watershed management programs. PWD operates one of the oldest water systems in the United States, but continues to modernize its facilities and embrace innovative approaches like green infrastructure for stormwater management. The city has made significant investments in reducing combined sewer overflows and improving overall water quality through comprehensive watershed protection and advanced treatment technologies.
Philadelphia Water Quality: Current Status (2024-2025)
Latest Testing Results
- Lead Levels: The most recent testing period (January-December 2023) showed 90th percentile lead levels of 8.2 parts per billion (ppb), below the EPA action level of 15 ppb but higher than many newer water systems.
- Testing Scope: Philadelphia conducts over 500,000 water quality tests annually, including lead and copper monitoring at 100 high-risk residential sites selected based on age of plumbing and likelihood of lead presence.
- Compliance Status: Philadelphia’s water meets all federal and state drinking water standards for regulated contaminants. The system has maintained compliance with the Lead and Copper Rule since its implementation.
Source Water Protection
- Watershed Management: PWD manages over 17,000 acres of watershed lands in the city’s Schuylkill and Delaware river basins, implementing conservation practices to protect source water quality at its origins.
- River Water Quality: Both the Delaware and Schuylkill rivers have shown significant improvements in water quality over recent decades due to federal regulations and local watershed protection efforts.
- Drinking Water Intakes: Philadelphia’s three water treatment plants draw water from carefully selected points along the rivers to maximize source water quality and minimize treatment challenges.
Advanced Treatment Technology
- Pilot Treatment Programs: PWD is conducting pilot programs with advanced treatment technologies including granular activated carbon and membrane bioreactors to address emerging contaminants like PFAS.
- UV Disinfection: The Baxter and Belmont treatment plants utilize ultraviolet light disinfection in combination with chloramination to ensure microbiological safety while minimizing disinfection byproducts.
- Corrosion Control: Philadelphia implements optimal corrosion control treatment using zinc orthophosphate to minimize lead and copper leaching from plumbing systems.
Infrastructure Modernization
- Main Replacement Program: PWD is replacing approximately 40 miles of water mains annually, prioritizing pipes from the 1950s and earlier that have historically higher break rates.
- Green Stormwater Infrastructure: Philadelphia is leading the nation with over 1,100 green infrastructure projects including rain gardens, permeable pavement, and green roofs to reduce combined sewer overflows.
- Lead Service Line Initiative: PWD launched a comprehensive lead service line inventory project to identify all lead service lines in the system, estimating approximately 70,000 lines need assessment or replacement.
Drinking Water Innovations
Philadelphia is developing one of the nation’s most ambitious green infrastructure programs, using natural systems to improve water quality. The city’s Green Cities, Clean Waters initiative includes comprehensive watershed restoration, stream monitoring, and community engagement programs. PWD also operates a nationally recognized research and development program focused on emerging contaminants, climate change adaptation, and sustainable water management practices.
Recommendations for Philadelphia Residents
Use Filtered Water
If your home was built before 1987 or has lead service lines, use NSF-certified water filters (Standard 53) for drinking and cooking water. Philadelphia offers free filters to residents in targeted neighborhoods.
Get Free Water Testing
Philadelphia offers free lead testing for all residents. Call the Lead Paint Disclosure and Testing Hotline at (215) 685-2797 or visit phila.gov/water to schedule testing of your tap water.
Check Service Lines
Use Philadelphia’s online service line lookup tool to check if your property has a lead service line. Call 311 for assistance or to schedule a professional inspection through PWD’s Lead Service Line Program.
Frequently Asked Questions
Is Philadelphia’s tap water safe to drink?
Yes, Philadelphia’s tap water meets all federal and state drinking water standards and is tested over 500,000 times annually. The city treats water from the Delaware and Schuylkill rivers using advanced filtration and disinfection processes.
While the water leaving the treatment plants is safe, homes built before 1987 may have lead in their plumbing. Philadelphia Water Department recommends using NSF-certified filters if you live in older homes or apartments, especially if children or pregnant women are present. Free water testing and filters are available for qualifying residents.
How do I know if I have a lead service line?
Most Philadelphia homes built before 1950 have lead service lines. To check your property:
1. Use Philadelphia’s online service line lookup tool at pwdmaps.phila.gov/serviceLineLookup
2. Look for the water service line where it enters your home (usually in the basement). Lead pipes are dull gray, soft enough to scratch with a key, and won’t attract a magnet.
3. Call 311 to request a professional evaluation through PWD’s Lead Service Line Program.
PWD is working to inventory all service lines and offers free replacements for qualifying low-income households.
What is Philadelphia doing about PFAS in drinking water?
Philadelphia proactively monitors for PFAS (per- and polyfluoroalkyl substances) and currently detects these compounds at very low levels, well below EPA advisory levels. PWD is:
• Conducting pilot studies with granular activated carbon and other advanced treatment technologies
• Installing full-scale PFAS treatment at the Belmont and Baxter water treatment plants (scheduled for completion in 2025-2026)
• Working with upstream communities to reduce PFAS sources in the watersheds
• Publishing PFAS test results quarterly at phila.gov/water
Philadelphia will meet all future PFAS regulations and is preparing for the EPA’s upcoming National Primary Drinking Water Regulation for PFAS.
Why does Philadelphia water sometimes taste or smell different?
Occasional changes in taste or odor can occur for several reasons:
• Seasonal variation: Warmer temperatures may increase chlorine odors as disinfection levels are adjusted
• Source switching: When PWD switches between Delaware and Schuylkill river sources, slight differences in mineral content may be noticeable
• Harmless algae: Natural algae growth in reservoirs can create earthy or musty tastes, especially in warmer months
These changes don’t affect water safety. For persistent issues, call PWD at (215) 685-6300. Refrigerating water in an open container can improve taste.
Contaminants of Concern
PFAS Compounds
Source: Industrial discharges, firefighting foam, consumer products, and wastewater treatment plant discharges upstream
Health Effects: Potential increased risks of cancer, decreased vaccine response, increased cholesterol, and reproductive effects
Current Status: Present at very low levels; PWD installing advanced treatment by 2026 to be ahead of federal regulations
Lead
Source: Lead service lines (especially pre-1950 construction), lead solder, and older plumbing fixtures
Health Effects: Developmental delays in children, reduced IQ, learning difficulties, kidney damage, cardiovascular effects in adults
Current Levels: 90th percentile value of 8.2 ppb EPA Limit: Action level 15 ppb, but no level of lead is considered safe
Please read – our information
The information presented on cleanairandwater.net is compiled from official water quality reports, trusted news sources, government websites, and public health resources. While we strive for accuracy and thoroughness in our presentations, we are not scientists, engineers, or qualified water quality professionals.
Our mission is to present water quality information in an accessible, real-world format that helps people understand what’s in their water and make informed decisions about their health and safety. We believe that complex environmental information should be available to everyone in a format that’s easy to understand.
We make every effort to ensure our content is current and accurate, but we cannot guarantee that all information is complete or error-free. This website should not replace official communications from your local water utility or health department. We always recommend consulting official sources for the most up-to-date information regarding your specific water system.
Clean Air and Water is not liable for any unintentional errors, omissions, or outdated information. The content on this site is provided for informational purposes only and should not be considered professional advice.
