Is Washington, DC tap water safe?
Supplied by D.C. Water and Sewer Authority · serves 632,323 people (133,500 connections) · Purchased surface water · EPA ID DC0000002
Data: U.S. EPA · How we read the data · How we check it
Most of Washington gets its water from D.C. Water and Sewer Authority. Parts of the city are served by 2 smaller systems: Joint Base Anacostia – Bolling Water System (20,411 people), Naval Station Washington – Wny Water System (16,800 people). Your water bill names your system.
Buys water from Washington Aqueduct Division.. Treated water bought from another system can carry that system's contaminants.
Summary
No federal limits exceeded in EPA data.
- PFAS
- Detected, below limit2 of 29 PFAS found at least once. All averages below the federal limits.
- Lead
- Below action level2 ppb (parts per billion) at the 90th percentile: 9 in 10 homes sampled were at or below it. Action level 15 ppb, falling to 10 ppb in Nov 2027. Monitoring period ending Jun 2026. Your home's pipes can make yours higher.
- Violations
- None health-basedNo health-based violations since 2016.
- Built before 1986, or not sure what your service line is made of? Check your service line and test your tap. Utility data can't show your pipes.
- Tested your own tap? Compare your result with these numbers. Moving? Compare this system with another.
- Read D.C. Water and Sewer Authority's 2025 water quality report (Consumer Confidence Report, from the utility). It lists every regulated contaminant tested, including ones not on this page. Questions: (202) 364-3131.
PFAS (“forever chemicals”)
EPA UCMR 5: 2 entry points tested Jan 2024 to Oct 2024. "Average" is the highest entry-point average (non-detects counted as zero), the way EPA compares UCMR 5 results to the limits. ppt = parts per trillion. These results do not determine compliance.
| Contaminant | Highest average |
|---|---|
| PFOA Not detected Limit 4 ppt | – |
| PFOS Not detected Limit 4 ppt | – |
| PFHxS Not detected Limit 10 ppt | – |
| PFNA Not detected Limit 10 ppt | – |
| HFPO-DA (GenX) Not detected Limit 10 ppt | – |
| Hazard Index (a combined score for PFHxS, PFNA, GenX and PFBS, where above 1 is over the limit) Not detected Limit 1 | – |
| PFBS Not detected Guideline 2,000 ppt | – |
| PFBA Not detected Guideline 6,000 ppt | – |
| PFHxA Detected, below limit Guideline 3,000 ppt | 0.78 ppt |
| PFPeA Detected, no limit | 1.18 ppt |
29 PFAS tested, 2 detected at least once. "Not detected" means below EPA's reporting limit (about 2 to 20 ppt depending on the chemical), not proven zero. PFAS not listed were not detected. The limits for PFHxS, PFNA, GenX and the Hazard Index were proposed for rescission in May 2026. That proposal is not final. Systems have until 2029 to meet the limits.
Lithium
Not detected in 8 samples (reporting limit 9 ppb). About lithium.
Lead and copper
Latest 90th percentile: 2 ppb lead (Jan 2026 – Jun 2026). Below action level
Highest since 2016: 3.4 ppb (Dec 2017).
| Monitoring period | Lead (90th pct.) |
|---|---|
| Jan 2026 – Jun 2026 | 2 ppb |
| Jul 2025 – Dec 2025 | 2 ppb |
| Jan 2025 – Jun 2025 | 1 ppb |
Earlier results (9)
| Jul 2024 – Dec 2024 | 2 ppb |
| Jan 2024 – Jun 2024 | 2 ppb |
| Jul 2023 – Dec 2023 | 2 ppb |
| Jan 2023 – Jun 2023 | 2 ppb |
| Jul 2022 – Dec 2022 | 2 ppb |
| Jan 2022 – Jun 2022 | 2 ppb |
| Jul 2021 – Dec 2021 | 3 ppb |
| Jan 2021 – Jun 2021 | 2 ppb |
| Jul 2020 – Dec 2020 | 3 ppb |
Lead service lines: D.C. Water and Sewer Authority publishes a service line inventory where you can look up what your line is made of. It doesn't publish summary counts.
Look up your address · Source (the utility, collected by us on Nov 14, 2026, not EPA data) · Checking your own line
Lead comes from pipes and fixtures, not the source water, so it varies home to home. The 90th percentile means 9 in 10 sampled homes were at or below it. More on lead.
Violations
Health-based violations mean a contaminant exceeded a limit or a required treatment step was missed. Monitoring and reporting violations mean required tests or reports were late or missing, so the water's quality during that time is unknown. The total includes every violation in EPA's records, most of them paperwork.
Earlier EPA testing (2013–2020)
| Contaminant | Highest | Guideline |
|---|---|---|
| Manganese | 1.2 ppb | 300 ppb |
| Strontium | 0.26 ppm | 1.5 ppm |
| Molybdenum | 1.2 ppb | 40 ppb |
| Chlorate | 470 ppb | 210 ppb |
| Chromium-6 | 0.12 ppb | – |
| Vanadium | 1.3 ppb | 21 ppb |
Where it serves
Washington
270 ZIP codes the system reported serving
20001, 20002, 20003, 20004, 20005, 20006, 20007, 20008, 20009, 20010, 20011, 20012, 20013, 20015, 20016, 20017, 20018, 20019, 20020, 20022, 20024, 20026, 20027, 20029, 20030, 20032, 20033, 20035, 20036, 20037, 20038, 20039, 20040, 20041, 20042, 20043, 20044, 20045, 20047, 20049, 20050, 20052, 20053, 20055, 20056, 20057, 20058, 20059, 20060, 20061, 20062, 20063, 20064, 20065, 20066, 20067, 20068, 20069, 20070, 20071, 20073, 20074, 20075, 20076, 20077, 20078, 20080, 20081, 20082, 20090, 20091, 20201, 20202, 20203, 20204, 20206, 20207, 20208, 20210, 20211, 20212, 20213, 20214, 20215, 20216, 20217, 20218, 20219, 20220, 20221, 20222, 20223, 20224, 20226, 20227, 20228, 20229, 20230, 20232, 20233, 20235, 20237, 20238, 20239, 20240, 20241, 20242, 20244, 20245, 20250, 20251, 20252, 20254, 20260, 20261, 20262, 20265, 20266, 20268, 20270, 20277, 20289, 20299, 20301, 20303, 20306, 20310, 20314, 20317, 20318, 20319, 20330, 20340, 20350, 20355, 20370, 20372, 20373, 20374, 20375, 20376, 20380, 20388, 20389, 20390, 20391, 20392, 20393, 20394, 20395, 20398, 20401, 20402, 20403, 20404, 20405, 20406, 20407, 20408, 20410, 20411, 20412, 20413, 20414, 20415, 20416, 20417, 20418, 20419, 20420, 20421, 20422, 20423, 20424, 20425, 20426, 20427, 20428, 20429, 20431, 20433, 20434, 20435, 20436, 20437, 20439, 20440, 20441, 20442, 20444, 20447, 20451, 20453, 20456, 20460, 20463, 20468, 20469, 20470, 20472, 20500, 20501, 20502, 20503, 20504, 20505, 20506, 20507, 20508, 20509, 20510, 20511, 20515, 20520, 20521, 20522, 20523, 20524, 20525, 20526, 20527, 20528, 20529, 20530, 20531, 20533, 20534, 20535, 20536, 20537, 20538, 20539, 20540, 20541, 20542, 20543, 20544, 20546, 20547, 20548, 20549, 20551, 20552, 20553, 20554, 20555, 20557, 20559, 20560, 20565, 20566, 20570, 20571, 20572, 20573, 20575, 20576, 20577, 20578, 20579, 20580, 20581, 20585, 20586, 20590, 20591, 20593, 20594, 20597, 20599
Questions
Is Washington tap water safe to drink?
Most of Washington gets its water from D.C. Water and Sewer Authority. D.C. Water and Sewer Authority has no health-based violations since 2016. EPA testing found no PFAS above the federal limits. Federal data can't tell you about your own pipes: lead comes from service lines and plumbing, so test your tap if your home was built before 1986. For the official word, read the utility's annual Consumer Confidence Report.
Does Washington water have PFAS?
Yes. EPA's 2023–2025 testing of D.C. Water and Sewer Authority found 2 PFAS at least once. None of the averages were above the federal limits.
What is the lead level in Washington water?
The most recent 90th-percentile lead result for D.C. Water and Sewer Authority is 2 ppb, for the period ending Jun 2026. The federal action level is 15 ppb, falling to 10 ppb in November 2027. The 90th percentile means 9 in 10 homes sampled were at or below this number. Individual homes can be higher.
Check these numbers yourself
Every figure on this page comes from public EPA records. You don't have to take our word for it:
- EPA's own report for DC0000002: violations, enforcement and inspections, straight from EPA.
- EPA UCMR 5 data: the PFAS and lithium results (search the file for PWSID DC0000002).
- EPA SDWIS download: the lead results, population and violation records we use.
- D.C. Water and Sewer Authority's 2025 water quality report: the utility's own annual report, including contaminants EPA's national database doesn't carry (link checked Nov 14, 2026). Phone: (202) 364-3131.
- D.C. Water and Sewer Authority website
Found something that doesn't match? Tell us and we'll check it against EPA's records. How we check our data.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.