Washington, DC tap water: lead, PFAS and hardness

Supplied by DC Water (District of Columbia Water and Sewer Authority) · EPA ID DC0000002 · 632,323 people

By Daryna Klochko · Data checked Oct 13, 2026
Short answer

Washington, DC tap water comes from DC Water, which serves 632,323 people. In Jan – Jun 2026 sampling, the lead 90th percentile was 2 ppb, against the 15 ppb action level. UCMR 5 testing found no PFOA or PFOS at reporting levels, but 2 other PFAS were detected. Hardness is 139 mg/L (8.1 gpg) on average: hard. EPA lists no health-based violations in the last 10 years (4 monitoring, reporting or notice records).

Lead · 90th pct 2 ppb Action level 15 ppb · Jan – Jun 2026 PFAS · UCMR 5 No PFOA/PFOS 2 other PFAS found · Jan 2024 – Oct 2024 Hardness 139 mg/L 8.1 gpg · hard EPA violations · 10 yrs 4 records 0 health-based · 18 in all since 1998

These numbers describe the water system, not your tap. Lead and copper often come from pipes and fixtures inside a home, so your water can differ. Where a goal (MCLG) is 0, EPA’s goal for that contaminant is zero. Legal limits are set above it.

Is Washington, DC tap water safe to drink?

In the latest results, every contaminant we list with a single federal limit was below that limit or action level. Lead was 2 ppb at the 90th percentile, below the 15 ppb action level. EPA’s goal for lead is zero. EPA lists no health-based violations in the last 10 years (4 monitoring, reporting or notice records). See how US tap water compares nationally.

What’s in Washington, DC tap water

Latest results from DC Water’s 2025 report and EPA records. One row per contaminant, with the type of limit in the limit column.

ContaminantResultLimitSampledSource
LeadComes mostly from home plumbing, not from the source water. 2 ppb 90th percentile reported to EPA; previous round (Jul – Dec 2025): 2 ppb 15 ppbAction level · goal 0Drops to 10 ppb on Nov 1, 2027 (Lead and Copper Rule Improvements). Jan – Jun 2026 EPA SDWIS record, DC0000002
PFOA and PFOS (PFAS)Two “forever chemicals” with a federal limit. Not detected 8 samples at 2 entry points; none at or above the reporting level (4 ppt) 4.0 ppt eachLegal limit (MCL) · goal 0Utilities must comply from 2029; EPA proposed 2031 in May 2026. Jan 2024 – Oct 2024 EPA UCMR 5 final occurrence data (Aug 2026 release)
Other PFASFound among the 27 other PFAS EPA had utilities test. 2 found PFPeA up to 4.7 ppt; PFHxA up to 3.1 ppt VariesSet per compound in EPA’s PFAS rule Jan 2024 – Oct 2024 EPA UCMR 5 final occurrence data (Aug 2026 release)
Total trihalomethanesByproducts of disinfection. 50 ppb Highest locational running annual average; range 17–73 80 ppbLegal limit (MCL) 2025 DC Water 2026 Drinking Water Quality Report (2025 data)
Haloacetic acids (HAA5)Byproducts of disinfection. 34 ppb Highest locational running annual average; range 14–48 60 ppbLegal limit (MCL) 2025 DC Water 2026 Drinking Water Quality Report (2025 data)

ppb = parts per billion (µg/L), ppt = parts per trillion (ng/L). The bar shows the result against the limit (black line). Limits: EPA drinking water regulations, PFAS rule, Lead and Copper Rule Improvements. “Not detected” means below the lab’s reporting level, not zero.

EPA violations

EPA’s SDWIS database lists 18 violation records for DC Water since 1998, 5 of them health-based. All have a return-to-compliance date.

Jan 2023 · Monitoring and reporting Surface Water Treatment Rule Back in compliance Mar 9, 2023
Jan 2023 · Monitoring Revised Total Coliform Rule Back in compliance Mar 9, 2023
Dec 2022 · Monitoring Revised Total Coliform Rule Back in compliance Mar 9, 2023
Dec 2022 · Monitoring and reporting Surface Water Treatment Rule Back in compliance Mar 9, 2023
Oct 2004 · Treatment technique Lead and Copper Rule Health-based Back in compliance Mar 15, 2006
Oct 2002 · Treatment technique · 2 records Lead and Copper Rule Health-based Back in compliance Nov 18, 2005
Jul 2001 · Treatment technique · 2 records Lead and Copper Rule Health-based Back in compliance Nov 19, 2005

Not listed: 9 older monitoring, reporting or notice records (1998–2005), none health-based.

Shown: health-based violations and everything from the last 10 years. Source: EPA SDWIS record, DC0000002, retrieved Oct 13, 2026.

How hard is Washington, DC water?

139 mg/L (8.1 gpg)
Average, hard; range 84–194 mg/L

The utility’s figures cover the whole system. To test the hardness at your tap, strips or a drop kit take minutes.

Classes: USGS (0–60 mg/L soft, 61–120 moderately hard, 121–180 hard, above 180 very hard). 1 gpg = 17.1 mg/L as calcium carbonate. Source: DC Water 2026 Drinking Water Quality Report (2025 data).

What to do with these numbers

Only what the data above points to.

Lead · 2 ppb

Lead comes from home plumbing

EPA’s goal for lead is zero. Older faucets, lead solder and lead service lines can add lead at your tap. A filter certified to NSF/ANSI 53 for lead reduces it.

Certified to reduce lead. Lead is not necessarily in your water.

All filters compared →
Hardness · up to 139 mg/L

Hard water

Above 120 mg/L (7.1 gpg) USGS calls water hard. Hardness has no federal health limit, but it leaves scale in kettles, water heaters and on fixtures. Filters for lead or chloramine do not reduce it. A water softener at the main line does.

Whole-house systems compared →
Chloramine

Chloramine taste and smell

DC Water disinfects with chloramine on purpose. If you dislike the taste, look for a filter certified to NSF/ANSI 42 for chloramine. For home dialysis and aquariums it must be reduced first.

Certified to reduce chloramine.

Under-sink filters compared →
Your tap, not the system

Test your own water

DC Water’s numbers come from its own sampling sites. A certified lab test of your faucet shows lead and copper from your plumbing and the chloramine level at your tap. How to test your own tap for lead, starting with your water utility.

All water tests compared →

Questions people ask

Does Washington, DC tap water have lead?
In Jan – Jun 2026 sampling, DC Water’s lead 90th percentile was 2 ppb (90th percentile reported to EPA; previous round (Jul – Dec 2025): 2 ppb). The federal action level is 15 ppb, and EPA’s goal is zero. Lead usually enters water from home plumbing, so only a test of your own tap shows your level.
Does Washington, DC tap water have PFAS?
UCMR 5 testing (Jan 2024 – Oct 2024, 2 entry points) found no PFOA or PFOS at reporting levels, but 2 other PFAS were detected. Other PFAS found: PFPeA up to 4.7 ppt, PFHxA up to 3.1 ppt. The federal limit for PFOA and PFOS is 4.0 ppt each, based on a running annual average. Utilities must comply from 2029. On May 18, 2026 EPA proposed letting systems ask for two more years, to 2031, and dropping the 2024 limits for PFHxS, PFNA, HFPO-DA and PFAS mixtures (the Hazard Index).
Is Washington, DC water hard?
DC Water reports an average hardness of 139 mg/L (8.1 gpg), ranging from 84 to 194 mg/L. By USGS classes that is hard.
Does Washington, DC use chlorine or chloramine?
DC Water disinfects with chloramine. DC Water’s report notes a temporary switch to free chlorine each spring.
Has DC Water had EPA violations?
EPA’s SDWIS database lists 18 violation records for DC Water since 1998, 5 of them health-based. All have a return-to-compliance date. EPA lists no health-based violations in the last 10 years (4 monitoring, reporting or notice records).
Who supplies water in Washington, DC?
DC Water (District of Columbia Water and Sewer Authority) (EPA ID DC0000002), a community water system serving 632,323 people through 133,500 connections. Main source: purchased surface water.

Sources and nearby

DC Water 2026 Drinking Water Quality Report (2025 data)dcwater.com EPA record for DC Water (DC0000002)echo.epa.gov EPA UCMR 5 data (PFAS and lithium)epa.gov Baltimore tap waterMDRichmond tap waterVAPhiladelphia tap waterPA How we researchMethod