Washington DC (District of Columbia)
Washington DC’s drinking water comes from the Potomac River and meets all federal compliance standards as of 2024. However, the city faces ongoing challenges with lead service lines (over 41,000 still need replacement) and certain contaminants that exceed health guidelines recommended by independent scientists, though they meet current federal limits. DC Water has implemented a $1.5 billion Lead Free DC program with the goal of replacing all lead pipes by 2030, with about 4,300 lines replaced since the program began in 2019.
Washington DC Water Quality: Current Status (2024-2025)
- Water Source: All water in Washington DC comes from the Potomac River near Great Falls, treated at the Dalecarlia Reservoir by the Washington Aqueduct (a division of the U.S. Army Corps of Engineers), and then sold to DC Water. Epicwaterfilters
- Distribution System: Water is pumped to reservoirs throughout the city, which are located at different elevations to supply water to points below them, flowing downhill via gravity to homes and businesses. Epicwaterfilters
- Monitoring: DC Water’s monitoring program tests more than 40,000 samples annually from various sources across the District, exceeding requirements to ensure clean and reliable water delivery. Dcwater
Lead Service Line Status
- Total Lead Lines: DC Water estimates the District has more than 42,000 service lines with lead or galvanized-iron pipe that need replacement with copper pipe. Dcwater As of June 2023, DC Water estimated 41,157 service lines will need to be replaced through the Lead Free DC program. Wusa9
- Replacement Progress: As of May 2023, Lead Free DC has replaced 4,287 lead service lines with copper pipes since 2019. Wusa9
- Replacement Goal: DC Water has released a plan to replace all lead pipelines by 2030, with an estimated cost of $1.5 billion, a significant increase from the original estimate of $300-500 million. WTOP News
- Replacement Programs: The District allocated $8.5 million to DC Water in FY22 to cover the complete cost of lead water service pipe replacement on private property when DC Water replaces the public portion during capital improvement projects. Dc
Water Quality Testing Results
- Compliance Status: For the latest quarter assessed by the EPA (April-June 2024), DC’s tap water was in compliance with federal health-based drinking water standards. Ewg
- Contaminant Concerns: According to the Environmental Working Group (EWG), test results through 2024 showed 37 contaminants in DC’s water, with 13 at levels above EWG’s health-based limits. Ewg
- Key Contaminants: Key contaminants of concern include TTHMs (total trihalomethanes), chromium, arsenic, radium, and haloacetic acids (HAA5), some at levels exceeding EWG’s recommended health guidelines. HomeWater
Health Concerns and Context
- Lead Exposure History: In 2016, researcher Marc Edwards estimated that Washington DC’s earlier lead crisis was “20 to 30 times worse” than the Flint water crisis, according to testimony cited by The Washington Post. Wikipedia
- Current Perspective: According to environmental advocates, the city’s lead pipes continue to contribute to contamination, though paradoxically DC is in compliance with federal drinking water regulations for lead due to what they describe as “a confusing and inadequate system of safeguards.” Nrdc
- Health Guidelines vs. Regulations: Federal compliance doesn’t guarantee water meets latest health guidelines, as legal limits for contaminants haven’t been updated in almost 20 years. Ewg
Ongoing Monitoring and Resources
Annual Reporting: The District of Columbia publishes an Integrated Report that provides information on the city’s water quality, combining reporting requirements of the Clean Water Act. Dcnk from their taps despite improvements. Jamie Davis, a Flint resident, says “I don’t think I’ll ever get to the point where I’m comfortable [using the water] without it being filtered.” Acs
Service Line Map: DC Water has created an interactive map showing residents which pipe lines are made of lead or other potentially dangerous metals, with information gathered from historical data and inspections. Wikipedia
Water Testing: Residents can call DC Water at 202-787-4044 to request a water test kit if concerned about lead in their tap water. Dc
Frequently Asked Questions
Is Washington DC’s tap water safe to drink?
The water meets all federal standards enforced by the EPA and is considered safe to drink. However, lead can leach from lead service lines and home plumbing, particularly in older homes. If you have lead pipes, using an NSF-certified filter (Standard 53) provides an extra layer of protection, especially for households with children, pregnant women, or elderly residents.
How do I know if my home has a lead service line?
DC Water maintains an interactive map of service line materials throughout the city. Visit geo.dcwater.com/Lead and enter your address. The map shows whether your public and private service lines are made of lead, copper, or other materials. If information is unavailable or you’re unsure, you can request an inspection by calling DC Water at 202-787-4044.
What contaminants are of concern in DC’s water?
While DC’s water meets federal standards, the Environmental Working Group (EWG) has identified several contaminants that exceed their recommended health guidelines, including disinfection byproducts (TTHMs and haloacetic acids), chromium, arsenic, and radium. These contaminants may pose long-term health concerns despite being below federal legal limits, which environmental advocates argue haven’t been updated to reflect current science.
How much will it cost to replace my lead service line?
The cost of replacing lead service lines on private property typically ranges from $2,000-$3,000. However, DC has established funding programs to assist homeowners. If DC Water is already replacing public lines in your area, replacement of your private line may be covered at no cost. Other assistance programs are available for eligible residents outside of scheduled capital improvement projects.
Contaminants of Concern
Chromium (including Hexavalent Chromium)
Primary source: Natural deposits and industrial pollution
Health concerns: Known carcinogen, particularly hexavalent chromium (made famous by the Erin Brockovich case)
Status: Chromium levels in Washington DC water have exceeded Environmental Working Group’s recommended safety levels by 4.3 times
Lead
Primary source: Lead service lines and old plumbing fixtures
Health concerns: Developmental delays in children, learning difficulties, kidney problems, high blood pressure
Status: While overall levels meet federal standards, homes with lead service lines remain at risk Most lead pipes in DC have not been replaced and those remaining may cause contamination issues for residents