Drinking water quality · 2023
· Verified
What's in Washington Dc, DC tap water
32 contaminants were measured in the Washington Dc, DC water system's 2023 annual report. Each is shown below against its federal limit.
- Reporting year
- 2023
- Contaminants measured
- 32
- Over federal limit
- 0
- Approaching the limit
- 0
- Service area
- DC
Where your water comes from · EPA SDWIS
Washington Dc, DC buys its drinking water from WASHINGTON AQUEDUCT DIVISION..
Source
Treatment
Distribution
Also buys water from WASHINGTON AQUEDUCT DIVISION..
Compliance history
Federal Safe Drinking Water Act violation & enforcement records (EPA SDWIS). A violation is a regulatory determination by the state or EPA — separate from the measured levels above.
- Maximum contaminant level exceededHealth-based9 violations on record · most recent Sep 2004resolved
- Treatment technique violationHealth-based5 violations on record · most recent Oct 2004resolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗
PFAS ("forever chemicals")
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| PFOSPerfluorooctanesulfonic acid, a PFAS 'forever chemical' once used in firefighting foam and coatings. | 2.1 ng/LAverageSystem-wide | 4 ng/LMCL | Within the limit |
| PFOAPerfluorooctanoic acid, a PFAS 'forever chemical' once used in nonstick and stain-resistant products. | 1.5 ng/LAverageSystem-wide | 4 ng/LMCL | Within the limit |
| Perfluorohexanesulfonic acidPerfluorohexanesulfonic acid, a PFAS 'forever chemical.' | 0.2 ng/LAverageSystem-wide | 10 ng/LMCL | Within the limit |
| Hexafluoropropylene oxide dimer acidHFPO-DA ('GenX chemicals'), a newer-generation PFAS replacement compound. | 0.001 ng/LAverageSystem-wide | None set | Within the limit |
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| TTHMTotal trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter. | 41 ug/LAverageSystem-wide | None set | Within the limit |
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | 28 ug/LAverageSystem-wide | None set | Within the limit |
| PerchlorateA chemical used in rocket fuel and fireworks that can also form during disinfection. | 0.2 ug/LAverageSystem-wide | None set | Detected — no federal limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| NitrateA compound from fertilizer runoff, septic systems, and erosion of natural deposits. | 2 mg/LMaximumDC Drinking Water | 10 mg/LMCLG | Within the limit |
| FluorideA mineral often added to drinking water to help prevent tooth decay. | 0.7 mg/LMaximumDC Drinking Water | 4 mg/LMCLG | Within the limit |
| Ammonia | 1 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| ChlorideA naturally occurring salt compound. | 32 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| SulfateA naturally occurring mineral from rock and soil. | 47 mg/LAverageSystem-wide | None set | Detected — no federal limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | 0.002 mg/L90th percentileAt the tap | 0.015 mg/LAction level | Within the limit |
| ArsenicA naturally occurring element that also enters water from industry and agriculture. | 0.4 ug/LMaximumDC Drinking Water | 0 ug/LMCLG | Within the limit |
| BariumA metal from erosion of natural deposits and industrial discharge. | 0.04 mg/LMaximumDC Drinking Water | 2 mg/LMCLG | Within the limit |
| AluminumA common element sometimes used as a treatment coagulant. | 39 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| CalciumA naturally occurring mineral that contributes to water hardness. | 39 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| IronA naturally occurring metal common in groundwater. | Not detected ug/LAverageSystem-wide | None set | Detected — no federal limit |
| LithiumA naturally occurring element found in some groundwater. | 2 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 9 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| ManganeseA naturally occurring metal from soil and rock. | 0.3 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| NickelA metal from natural deposits and industrial discharge. | 0.3 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| PotassiumA naturally occurring mineral from rock and soil. | 3 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 22 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| Strontium | 187 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| Vanadium | Not detected ug/LAverageSystem-wide | None set | Detected — no federal limit |
| ZincA naturally occurring metal that can also enter water from corroding pipes. | Not detected ug/LAverageSystem-wide | None set | Detected — no federal limit |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 0.2 mg/LRangeSystem-wide | 4 mg/LMCLG | Within the limit |
Other
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Twofourd | 0.6 ug/LMaximumSystem-wide | None set | Within the limit |
VOCs & pesticides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Dalapon | 1 ug/LMaximumSystem-wide | 200 ug/LMCLG | Within the limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| HardnessA measure of dissolved calcium and magnesium minerals. | 8AverageSystem-wide | None set | Detected — no federal limit |
| TOCTotal organic carbon — a measure of organic material dissolved in the water. | 1.37Reported levelDC Drinking Water | None set | Detected — no federal limit |
People also ask about Washington Dc, DC's water
+Is Washington Dc, DC tap water safe to drink in 2023?
Every one of the 32 contaminants measured in Washington Dc, DC's 2023 Consumer Confidence Report is below its federal limit. "Safe" under the EPA's drinking-water standards is health-based, not aesthetic — but by those standards, no measured contaminant in this report exceeds its enforceable threshold. Individual health concerns (e.g. immunocompromised, infant, pregnancy) may warrant additional filtering regardless of compliance.
+What contaminants are in Washington Dc, DC tap water?
32 contaminants were measured in Washington Dc, DC's 2023 Consumer Confidence Report, spanning metals, inorganic chemicals, and pfas ("forever chemicals"). 10 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Where does the data on this page come from?
Every value is transcribed from Washington Dc, DC's 2023 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.
+How often is Washington Dc, DC's water quality data updated?
Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2023 report; a new report will replace it once the utility publishes its next annual update.