Recent monitoring in Washington shows middle-tier safety for DC — some systems are clean; others have logged EPA violations.

Data: EPA SDWIS Last verified: 2026-06-03

Water Quality Map: Washington, DC

Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.

A B C D F

Overview

We track water quality and home safety data for 274 ZIP codes in Washington, District of Columbia, covering 4 community water systems serving approximately 671,768 people.

274 of 274 ZIP codes (100%) have recorded EPA violations. 1644 health-based violations documented.

Home Safety Score

Average Home Safety Score for Washington: C (69/100)

The score combines three factors:

Factor	What It Measures
Water Quality	EPA violations and compliance history
Lead Levels	90th percentile lead concentration vs EPA action level
Radon Risk	EPA radon zone classification

Water Sources

Washington water systems draw from: Surface water.

Lead & Copper

• Average lead level (90th percentile): 0.0010 mg/L (EPA action level: 0.015 mg/L)
• 0 ZIP codes exceed the EPA lead action level

Radon Risk

Dominant radon zone: Zone 1 (High Risk)

• Zone 1 (High): 0 ZIP codes
• Zone 2 (Moderate): 0 ZIP codes
• Zone 3 (Low): 0 ZIP codes

The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.

Top Contaminants

Areas with Most Violations

All ZIP Codes in Washington

• 20001 [C] — 33 violations ⚠
• 20002 [C] — 33 violations ⚠
• 20003 [B] — 33 violations ⚠
• 20004 [B] — 33 violations ⚠
• 20005 [B] — 33 violations ⚠
• 20006 [B] — 33 violations ⚠
• 20007 [C] — 33 violations ⚠
• 20008 [C] — 33 violations ⚠
• 20009 [C] — 33 violations ⚠
• 20010 [C] — 33 violations ⚠
• 20011 [C] — 33 violations ⚠
• 20012 [C] — 33 violations ⚠
• 20013 [C] — 33 violations ⚠
• 20015 [C] — 33 violations ⚠
• 20016 [C] — 33 violations ⚠
• 20017 [C] — 33 violations ⚠
• 20018 [C] — 33 violations ⚠
• 20019 [C] — 33 violations ⚠
• 20020 [C] — 33 violations ⚠
• 20022 [C] — 33 violations ⚠
• 20023 [C] — 33 violations ⚠
• 20024 [B] — 33 violations ⚠
• 20026 [C] — 33 violations ⚠
• 20027 [B] — 33 violations ⚠
• 20029 [C] — 33 violations ⚠
• 20030 [C] — 33 violations ⚠
• 20032 [B] — 33 violations ⚠
• 20033 [C] — 33 violations ⚠
• 20035 [C] — 33 violations ⚠
• 20036 [B] — 33 violations ⚠
• 20037 [B] — 33 violations ⚠
• 20038 [C] — 33 violations ⚠
• 20039 [C] — 33 violations ⚠
• 20040 [C] — 33 violations ⚠
• 20041 [C] — 33 violations ⚠
• 20042 [C] — 33 violations ⚠
• 20043 [C] — 33 violations ⚠
• 20044 [C] — 33 violations ⚠
• 20045 [C] — 33 violations ⚠
• 20046 [C] — 33 violations ⚠
• 20047 [C] — 33 violations ⚠
• 20049 [C] — 33 violations ⚠
• 20050 [C] — 33 violations ⚠
• 20051 [C] — 33 violations ⚠
• 20052 [C] — 33 violations ⚠
• 20053 [C] — 33 violations ⚠
• 20055 [C] — 33 violations ⚠
• 20056 [C] — 33 violations ⚠
• 20057 [C] — 33 violations ⚠
• 20058 [C] — 33 violations ⚠
• 20059 [C] — 33 violations ⚠
• 20060 [C] — 33 violations ⚠
• 20061 [C] — 33 violations ⚠
• 20062 [C] — 33 violations ⚠
• 20063 [C] — 33 violations ⚠
• 20064 [C] — 33 violations ⚠
• 20065 [C] — 33 violations ⚠
• 20066 [C] — 33 violations ⚠
• 20067 [C] — 33 violations ⚠
• 20068 [C] — 33 violations ⚠
• 20069 [C] — 33 violations ⚠
• 20070 [C] — 33 violations ⚠
• 20071 [C] — 33 violations ⚠
• 20073 [C] — 33 violations ⚠
• 20074 [C] — 33 violations ⚠
• 20075 [C] — 33 violations ⚠
• 20076 [C] — 33 violations ⚠
• 20077 [C] — 33 violations ⚠
• 20078 [C] — 33 violations ⚠
• 20080 [C] — 33 violations ⚠
• 20081 [C] — 33 violations ⚠
• 20082 [C] — 33 violations ⚠
• 20088 [C] — 33 violations ⚠
• 20090 [C] — 33 violations ⚠
• 20091 [C] — 33 violations ⚠
• 20097 [C] — 33 violations ⚠
• 20098 [C] — 33 violations ⚠
• 20201 [C] — 33 violations ⚠
• 20202 [C] — 33 violations ⚠
• 20203 [C] — 33 violations ⚠
• 20204 [C] — 33 violations ⚠
• 20206 [C] — 33 violations ⚠
• 20207 [C] — 33 violations ⚠
• 20208 [C] — 33 violations ⚠
• 20210 [C] — 33 violations ⚠
• 20211 [C] — 33 violations ⚠
• 20212 [C] — 33 violations ⚠
• 20213 [C] — 33 violations ⚠
• 20214 [C] — 33 violations ⚠
• 20215 [C] — 33 violations ⚠
• 20216 [C] — 33 violations ⚠
• 20217 [C] — 33 violations ⚠
• 20218 [C] — 33 violations ⚠
• 20219 [C] — 33 violations ⚠
• 20220 [C] — 33 violations ⚠
• 20221 [C] — 33 violations ⚠
• 20222 [C] — 33 violations ⚠
• 20223 [C] — 33 violations ⚠
• 20224 [C] — 33 violations ⚠
• 20226 [C] — 33 violations ⚠
• 20227 [C] — 33 violations ⚠
• 20228 [C] — 33 violations ⚠
• 20229 [C] — 33 violations ⚠
• 20230 [B] — 33 violations ⚠
• 20232 [C] — 33 violations ⚠
• 20233 [C] — 33 violations ⚠
• 20235 [C] — 33 violations ⚠
• 20237 [C] — 33 violations ⚠
• 20238 [C] — 33 violations ⚠
• 20239 [C] — 33 violations ⚠
• 20240 [C] — 33 violations ⚠
• 20241 [C] — 33 violations ⚠
• 20242 [C] — 33 violations ⚠
• 20244 [C] — 33 violations ⚠
• 20245 [C] — 33 violations ⚠
• 20250 [C] — 33 violations ⚠
• 20251 [C] — 33 violations ⚠
• 20252 [C] — 33 violations ⚠
• 20254 [C] — 33 violations ⚠
• 20260 [C] — 33 violations ⚠
• 20261 [C] — 33 violations ⚠
• 20262 [C] — 33 violations ⚠
• 20265 [C] — 33 violations ⚠
• 20266 [C] — 33 violations ⚠
• 20268 [C] — 33 violations ⚠
• 20270 [C] — 33 violations ⚠
• 20277 [C] — 33 violations ⚠
• 20289 [C] — 33 violations ⚠
• 20299 [C] — 33 violations ⚠
• 20301 [C] — 33 violations ⚠
• 20303 [C] — 33 violations ⚠
• 20306 [C] — 33 violations ⚠
• 20307 [C] — 33 violations ⚠
• 20310 [B] — 33 violations ⚠
• 20314 [C] — 33 violations ⚠
• 20317 [C] — 33 violations ⚠
• 20318 [C] — 33 violations ⚠
• 20319 [C] — 33 violations ⚠
• 20330 [B] — 33 violations ⚠
• 20340 [C] — 33 violations ⚠
• 20350 [C] — 33 violations ⚠
• 20355 [C] — 33 violations ⚠
• 20370 [C] — 33 violations ⚠
• 20372 [C] — 33 violations ⚠
• 20375 [C] — 33 violations ⚠
• 20380 [C] — 33 violations ⚠
• 20389 [C] — 33 violations ⚠
• 20390 [C] — 33 violations ⚠
• 20392 [C] — 33 violations ⚠
• 20393 [C] — 33 violations ⚠
• 20394 [C] — 33 violations ⚠
• 20395 [C] — 33 violations ⚠
• 20401 [C] — 33 violations ⚠
• 20402 [C] — 33 violations ⚠
• 20403 [C] — 33 violations ⚠
• 20404 [C] — 33 violations ⚠
• 20405 [B] — 33 violations ⚠
• 20406 [C] — 33 violations ⚠
• 20407 [C] — 33 violations ⚠
• 20408 [C] — 33 violations ⚠
• 20409 [C] — 33 violations ⚠
• 20410 [C] — 33 violations ⚠
• 20411 [C] — 33 violations ⚠
• 20412 [C] — 33 violations ⚠
• 20413 [C] — 33 violations ⚠
• 20414 [C] — 33 violations ⚠
• 20415 [C] — 33 violations ⚠
• 20416 [C] — 33 violations ⚠
• 20417 [C] — 33 violations ⚠
• 20418 [C] — 33 violations ⚠
• 20419 [C] — 33 violations ⚠
• 20420 [C] — 33 violations ⚠
• 20421 [C] — 33 violations ⚠
• 20422 [C] — 33 violations ⚠
• 20423 [C] — 33 violations ⚠
• 20424 [C] — 33 violations ⚠
• 20425 [C] — 33 violations ⚠
• 20426 [C] — 33 violations ⚠
• 20427 [C] — 33 violations ⚠
• 20428 [C] — 33 violations ⚠
• 20429 [C] — 33 violations ⚠
• 20431 [C] — 33 violations ⚠
• 20433 [C] — 33 violations ⚠
• 20434 [C] — 33 violations ⚠
• 20435 [C] — 33 violations ⚠
• 20436 [C] — 33 violations ⚠
• 20437 [C] — 33 violations ⚠
• 20439 [C] — 33 violations ⚠
• 20440 [C] — 33 violations ⚠
• 20441 [C] — 33 violations ⚠
• 20442 [C] — 33 violations ⚠
• 20444 [C] — 33 violations ⚠
• 20447 [C] — 33 violations ⚠
• 20451 [C] — 33 violations ⚠
• 20453 [C] — 33 violations ⚠
• 20456 [C] — 33 violations ⚠
• 20460 [C] — 33 violations ⚠
• 20463 [C] — 33 violations ⚠
• 20468 [C] — 33 violations ⚠
• 20469 [C] — 33 violations ⚠
• 20470 [B] — 33 violations ⚠
• 20472 [C] — 33 violations ⚠
• 20500 [C] — 33 violations ⚠
• 20501 [C] — 33 violations ⚠
• 20502 [C] — 33 violations ⚠
• 20503 [C] — 33 violations ⚠
• 20504 [C] — 33 violations ⚠
• 20505 [C] — 33 violations ⚠
• 20506 [C] — 33 violations ⚠
• 20507 [C] — 33 violations ⚠
• 20508 [C] — 33 violations ⚠
• 20509 [C] — 33 violations ⚠
• 20510 [C] — 33 violations ⚠
• 20511 [C] — 33 violations ⚠
• 20515 [B] — 33 violations ⚠
• 20520 [B] — 33 violations ⚠
• 20521 [C] — 33 violations ⚠
• 20522 [C] — 33 violations ⚠
• 20523 [C] — 33 violations ⚠
• 20524 [C] — 33 violations ⚠
• 20525 [C] — 33 violations ⚠
• 20526 [C] — 33 violations ⚠
• 20527 [C] — 33 violations ⚠
• 20528 [C] — 33 violations ⚠
• 20529 [C] — 33 violations ⚠
• 20530 [B] — 33 violations ⚠
• 20531 [C] — 33 violations ⚠
• 20532 [C] — 33 violations ⚠
• 20533 [C] — 33 violations ⚠
• 20534 [C] — 33 violations ⚠
• 20535 [C] — 33 violations ⚠
• 20536 [C] — 33 violations ⚠
• 20537 [C] — 33 violations ⚠
• 20538 [C] — 33 violations ⚠
• 20539 [C] — 33 violations ⚠
• 20540 [C] — 33 violations ⚠
• 20541 [C] — 33 violations ⚠
• 20542 [C] — 33 violations ⚠
• 20543 [C] — 33 violations ⚠
• 20544 [C] — 33 violations ⚠
• 20546 [C] — 33 violations ⚠
• 20547 [C] — 33 violations ⚠
• 20548 [C] — 33 violations ⚠
• 20549 [C] — 33 violations ⚠
• 20551 [C] — 33 violations ⚠
• 20552 [C] — 33 violations ⚠
• 20553 [C] — 33 violations ⚠
• 20554 [C] — 33 violations ⚠
• 20555 [C] — 33 violations ⚠
• 20557 [C] — 33 violations ⚠
• 20558 [C] — 33 violations ⚠
• 20559 [C] — 33 violations ⚠
• 20560 [C] — 33 violations ⚠
• 20565 [C] — 33 violations ⚠
• 20566 [C] — 33 violations ⚠
• 20570 [C] — 33 violations ⚠
• 20571 [C] — 33 violations ⚠
• 20572 [C] — 33 violations ⚠
• 20573 [C] — 33 violations ⚠
• 20575 [C] — 33 violations ⚠
• 20576 [C] — 33 violations ⚠
• 20577 [C] — 33 violations ⚠
• 20578 [C] — 33 violations ⚠
• 20579 [C] — 33 violations ⚠
• 20580 [C] — 33 violations ⚠
• 20581 [C] — 33 violations ⚠
• 20585 [C] — 33 violations ⚠
• 20586 [C] — 33 violations ⚠
• 20590 [C] — 33 violations ⚠
• 20591 [C] — 33 violations ⚠
• 20593 [C] — 33 violations ⚠
• 20594 [C] — 33 violations ⚠
• 20597 [C] — 33 violations ⚠
• 20599 [C] — 33 violations ⚠

Data Sources

• Water quality: EPA Safe Drinking Water Information System (SDWIS)
• Lead/copper: EPA Lead and Copper Rule sampling data
• Radon: EPA Map of Radon Zones

Updated daily.

How Remediation Costs Compare in Washington

Equity impact data for Washington lands in the favorable tier — remediation claims a small slice of what properties here are worth.

Median Home Value

$727,800

Est. Remediation

$1,235

Remediation as % of home value 0.2%

Remediation costs in Washington are relatively low compared to home values. The $692–$2,498 estimated range is a small fraction of median property value. Home values are 1% below the District of Columbia average.

Washington: Lead Risk & Vulnerable Populations

0.001

mg/L Avg Lead (Limit: 0.015)

Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.

Lead risk in Washington appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.

Washington: Flood History & Water Damage Risk

The National Flood Insurance Program captures decades of claims at the local level, building a record of cumulative community flood exposure. For Washington, that record documents 503 claims and 9% of ZIP codes inside FEMA-designated flood zones. What makes those numbers relevant to water quality is the set of mechanisms flooding activates: heavy precipitation that floods treatment intake zones can introduce contaminants upstream of normal filtration; well casings in low-lying areas can be infiltrated by floodwaters carrying bacteria, sediment, and chemical residue; and distribution system pressure changes during flooding can create backflow conditions. These effects become more probable as flood frequency and magnitude increase — and the NFIP record indicates both are meaningful factors locally.

503

Total FEMA Flood Claims

$10,173

Avg Claim Payout

9%

ZIPs in FEMA Flood Zones

~25

Est. Claims/Year

Washington has a moderate flood history with 503 FEMA claims averaging $10,173 per payout. 9% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.

How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,235</strong> remediation cost per household.

Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.

Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.