COUNTY REPORT DC

District of Columbia County, District of Columbia

284 ZIP codes · Avg score 68/100 · Grade C · Updated 2026-06-04

Covering 284 ZIP codes, District of Columbia County falls in the average tier for tap water safety — violations appear in a meaningful share of areas, and the data suggests quality depends heavily on which specific part of the county a household sits in.

How District of Columbia County Compares

District of Columbia County68/100

District of Columbia avg68/100

National avg68/100

How District of Columbia County Compares

County Grade

68/100

Avg Safety Score

284

ZIP Codes

Water Systems

District of Columbia County scores 0 points above the District of Columbia state average (68/100) and 0 points above the national average (68/100).

Data: EPA SDWIS Last verified: 2026-06-04

County Grade

Avg Safety Score

284

ZIP Codes

Washington

Best ZIP: 20003 (72/100)

Parcel Return Service

Lowest ZIP: 56972 (50/100)

$725K

Median Home Value

$1,210

Avg Remediation (17% of home value)

ZIP Code Risk Map

Water Quality Map: District of Columbia County, District of Columbia

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

A B C D F

Key Risk Factors

Health risk index: 9.3 (asthma 10.2%, diabetes 7.8%)

Estimated additional annual cost per homeowner: $2,114, driven primarily by sea_level

Infrastructure: 0.396% avg pipe failure probability, 2% of ZIPs at high risk

Violation History (2022–2025)

→ Stable trend

EPA violation counts by year across District of Columbia County water systems. Health-based shown in red, total in blue.

2022

272 (272 health)

2023

272 (272 health)

2025

816 (816 health)

Peak year: 2025 with 816 violations. Past 5 years: 1360 total (1360 health-based).

Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.

County Health Indicators vs National Average

Asthma 10.2% (national: 8.9%)

Diabetes 7.8% (national: 10.5%)

Obesity 24.7% (national: 32.4%)

Black markers indicate national averages. Source: CDC PLACES, Census ACS.

Infrastructure Overview

40%

Pipe Failure Probability

ZIPs at High Infra Risk

Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.

Compound Risk Breakdown

Estimated additional annual cost per homeowner: $2,114

Sea Level Rise $1,500/yr

Underground Tanks $480/yr

Flood $71/yr

Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).

Water Safety Affordability

How much it costs to fix water issues relative to home values in District of Columbia County

$725K

Median Home Value

$1,210

Est. Remediation Cost

0.2%

of Home Value

Remediation as % of home value low burden

Remediation costs are relatively manageable for most homeowners in District of Columbia County, representing a small fraction of property value.

Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.

Health Outcomes vs National Average

CDC PLACES data for District of Columbia County residents

Asthma 10.2% (US avg: 8.9%)

Diabetes 7.8% (US avg: 11%)

Obesity 24.7% (US avg: 32.4%)

Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.

Water Systems with Most Violations

Top 4 systems in District of Columbia County ranked by EPA violation count.

#	Water System	Population	Violations
1	D.c. Water and Sewer Authority	632,323	8976
2	Joint Base Anacostia - Bolling	19,312	8976
3	Naval Station Washington - Wny	15,690	8976
4	Washington Aqueduct Division.	—	8976

Environmental Justice Indicator

District of Columbia County scores in the 73th percentile on the EPA EJScreen composite index, indicating elevated environmental burden relative to the national average. Approximately 35% of residents live in areas classified as disadvantaged communities. EJScreen measures cumulative environmental and demographic factors including air quality, proximity to hazardous sites, and socioeconomic vulnerability. Learn more at EPA.gov

All ZIP Codes in District of Columbia County

284 ZIP codes tracked in District of Columbia County.

#	ZIP Code	City	Safety Score	Grade	Violations	Home Value
1	20003	Washington	72	B	33 (6 health)	$954K
2	20004	Washington	72	B	33 (6 health)	$651K
3	20005	Washington	72	B	33 (6 health)	$636K
4	20006	Washington	72	B	33 (6 health)	$256K
5	20024	Washington	72	B	33 (6 health)	$497K
6	20027	Washington	72	B	33 (6 health)	—
7	20032	Washington	72	B	33 (6 health)	$391K
8	20036	Washington	72	B	33 (6 health)	$442K
9	20037	Washington	72	B	33 (6 health)	$744K
10	20230	Washington	72	B	33 (6 health)	—
11	20310	Washington	72	B	33 (6 health)	—
12	20330	Washington	72	B	33 (6 health)	—
13	20515	Washington	72	B	33 (6 health)	—
14	20520	Washington	72	B	33 (6 health)	—
15	20530	Washington	72	B	33 (6 health)	—
16	20013	Washington	69	C	33 (6 health)	—
17	20022	Washington	69	C	33 (6 health)	—
18	20023	Washington	69	C	33 (6 health)	—
19	20026	Washington	69	C	33 (6 health)	—
20	20029	Washington	69	C	33 (6 health)	—
21	20030	Washington	69	C	33 (6 health)	—
22	20033	Washington	69	C	33 (6 health)	—
23	20035	Washington	69	C	33 (6 health)	—
24	20038	Washington	69	C	33 (6 health)	—
25	20039	Washington	69	C	33 (6 health)	—
26	20040	Washington	69	C	33 (6 health)	—
27	20041	Washington	69	C	33 (6 health)	—
28	20042	Washington	69	C	33 (6 health)	—
29	20043	Washington	69	C	33 (6 health)	—
30	20044	Washington	69	C	33 (6 health)	—
31	20045	Washington	69	C	33 (6 health)	—
32	20046	Washington	69	C	33 (6 health)	—
33	20047	Washington	69	C	33 (6 health)	—
34	20049	Washington	69	C	33 (6 health)	—
35	20050	Washington	69	C	33 (6 health)	—
36	20051	Washington	69	C	33 (6 health)	—
37	20052	Washington	69	C	33 (6 health)	—
38	20053	Washington	69	C	33 (6 health)	—
39	20055	Washington	69	C	33 (6 health)	—
40	20056	Washington	69	C	33 (6 health)	—
41	20057	Washington	69	C	33 (6 health)	—
42	20058	Washington	69	C	33 (6 health)	—
43	20059	Washington	69	C	33 (6 health)	—
44	20060	Washington	69	C	33 (6 health)	—
45	20061	Washington	69	C	33 (6 health)	—
46	20062	Washington	69	C	33 (6 health)	—
47	20063	Washington	69	C	33 (6 health)	—
48	20064	Washington	69	C	33 (6 health)	—
49	20065	Washington	69	C	33 (6 health)	—
50	20066	Washington	69	C	33 (6 health)	—
51	20067	Washington	69	C	33 (6 health)	—
52	20068	Washington	69	C	33 (6 health)	—
53	20069	Washington	69	C	33 (6 health)	—
54	20070	Washington	69	C	33 (6 health)	—
55	20071	Washington	69	C	33 (6 health)	—
56	20073	Washington	69	C	33 (6 health)	—
57	20074	Washington	69	C	33 (6 health)	—
58	20075	Washington	69	C	33 (6 health)	—
59	20076	Washington	69	C	33 (6 health)	—
60	20077	Washington	69	C	33 (6 health)	—
61	20078	Washington	69	C	33 (6 health)	—
62	20080	Washington	69	C	33 (6 health)	—
63	20081	Washington	69	C	33 (6 health)	—
64	20082	Washington	69	C	33 (6 health)	—
65	20088	Washington	69	C	33 (6 health)	—
66	20090	Washington	69	C	33 (6 health)	—
67	20091	Washington	69	C	33 (6 health)	—
68	20097	Washington	69	C	33 (6 health)	—
69	20098	Washington	69	C	33 (6 health)	—
70	20201	Washington	69	C	33 (6 health)	—
71	20202	Washington	69	C	33 (6 health)	—
72	20203	Washington	69	C	33 (6 health)	—
73	20204	Washington	69	C	33 (6 health)	—
74	20206	Washington	69	C	33 (6 health)	—
75	20207	Washington	69	C	33 (6 health)	—
76	20208	Washington	69	C	33 (6 health)	—
77	20210	Washington	69	C	33 (6 health)	—
78	20211	Washington	69	C	33 (6 health)	—
79	20212	Washington	69	C	33 (6 health)	—
80	20213	Washington	69	C	33 (6 health)	—
81	20214	Washington	69	C	33 (6 health)	—
82	20215	Washington	69	C	33 (6 health)	—
83	20216	Washington	69	C	33 (6 health)	—
84	20217	Washington	69	C	33 (6 health)	—
85	20218	Washington	69	C	33 (6 health)	—
86	20219	Washington	69	C	33 (6 health)	—
87	20220	Washington	69	C	33 (6 health)	—
88	20221	Washington	69	C	33 (6 health)	—
89	20222	Washington	69	C	33 (6 health)	—
90	20223	Washington	69	C	33 (6 health)	—
91	20224	Washington	69	C	33 (6 health)	—
92	20226	Washington	69	C	33 (6 health)	—
93	20227	Washington	69	C	33 (6 health)	—
94	20228	Washington	69	C	33 (6 health)	—
95	20229	Washington	69	C	33 (6 health)	—
96	20232	Washington	69	C	33 (6 health)	—
97	20233	Washington	69	C	33 (6 health)	—
98	20235	Washington	69	C	33 (6 health)	—
99	20237	Washington	69	C	33 (6 health)	—
100	20238	Washington	69	C	33 (6 health)	—
101	20239	Washington	69	C	33 (6 health)	—
102	20240	Washington	69	C	33 (6 health)	—
103	20241	Washington	69	C	33 (6 health)	—
104	20242	Washington	69	C	33 (6 health)	—
105	20244	Washington	69	C	33 (6 health)	—
106	20245	Washington	69	C	33 (6 health)	—
107	20250	Washington	69	C	33 (6 health)	—
108	20251	Washington	69	C	33 (6 health)	—
109	20252	Washington	69	C	33 (6 health)	—
110	20254	Washington	69	C	33 (6 health)	—
111	20260	Washington	69	C	33 (6 health)	—
112	20261	Washington	69	C	33 (6 health)	—
113	20262	Washington	69	C	33 (6 health)	—
114	20265	Washington	69	C	33 (6 health)	—
115	20266	Washington	69	C	33 (6 health)	—
116	20268	Washington	69	C	33 (6 health)	—
117	20270	Washington	69	C	33 (6 health)	—
118	20277	Washington	69	C	33 (6 health)	—
119	20289	Washington	69	C	33 (6 health)	—
120	20299	Washington	69	C	33 (6 health)	—
121	20301	Washington	69	C	33 (6 health)	—
122	20303	Washington	69	C	33 (6 health)	—
123	20306	Washington	69	C	33 (6 health)	—
124	20307	Washington	69	C	33 (6 health)	—
125	20314	Washington	69	C	33 (6 health)	—
126	20317	Washington	69	C	33 (6 health)	—
127	20318	Washington	69	C	33 (6 health)	—
128	20319	Washington	69	C	33 (6 health)	—
129	20340	Washington	69	C	33 (6 health)	—
130	20350	Washington	69	C	33 (6 health)	—
131	20355	Washington	69	C	33 (6 health)	—
132	20370	Washington	69	C	33 (6 health)	—
133	20372	Washington	69	C	33 (6 health)	—
134	20375	Washington	69	C	33 (6 health)	—
135	20380	Washington	69	C	33 (6 health)	—
136	20389	Washington	69	C	33 (6 health)	—
137	20390	Washington	69	C	33 (6 health)	—
138	20392	Washington	69	C	33 (6 health)	—
139	20393	Washington	69	C	33 (6 health)	—
140	20394	Washington	69	C	33 (6 health)	—
141	20395	Washington	69	C	33 (6 health)	—
142	20401	Washington	69	C	33 (6 health)	—
143	20402	Washington	69	C	33 (6 health)	—
144	20403	Washington	69	C	33 (6 health)	—
145	20404	Washington	69	C	33 (6 health)	—
146	20406	Washington	69	C	33 (6 health)	—
147	20407	Washington	69	C	33 (6 health)	—
148	20408	Washington	69	C	33 (6 health)	—
149	20409	Washington	69	C	33 (6 health)	—
150	20410	Washington	69	C	33 (6 health)	—
151	20411	Washington	69	C	33 (6 health)	—
152	20412	Washington	69	C	33 (6 health)	—
153	20413	Washington	69	C	33 (6 health)	—
154	20414	Washington	69	C	33 (6 health)	—
155	20415	Washington	69	C	33 (6 health)	—
156	20416	Washington	69	C	33 (6 health)	—
157	20417	Washington	69	C	33 (6 health)	—
158	20418	Washington	69	C	33 (6 health)	—
159	20419	Washington	69	C	33 (6 health)	—
160	20420	Washington	69	C	33 (6 health)	—
161	20421	Washington	69	C	33 (6 health)	—
162	20422	Washington	69	C	33 (6 health)	—
163	20423	Washington	69	C	33 (6 health)	—
164	20424	Washington	69	C	33 (6 health)	—
165	20425	Washington	69	C	33 (6 health)	—
166	20426	Washington	69	C	33 (6 health)	—
167	20427	Washington	69	C	33 (6 health)	—
168	20428	Washington	69	C	33 (6 health)	—
169	20429	Washington	69	C	33 (6 health)	—
170	20431	Washington	69	C	33 (6 health)	—
171	20433	Washington	69	C	33 (6 health)	—
172	20434	Washington	69	C	33 (6 health)	—
173	20435	Washington	69	C	33 (6 health)	—
174	20436	Washington	69	C	33 (6 health)	—
175	20437	Washington	69	C	33 (6 health)	—
176	20439	Washington	69	C	33 (6 health)	—
177	20440	Washington	69	C	33 (6 health)	—
178	20441	Washington	69	C	33 (6 health)	—
179	20442	Washington	69	C	33 (6 health)	—
180	20444	Washington	69	C	33 (6 health)	—
181	20447	Washington	69	C	33 (6 health)	—
182	20451	Washington	69	C	33 (6 health)	—
183	20453	Washington	69	C	33 (6 health)	—
184	20456	Washington	69	C	33 (6 health)	—
185	20460	Washington	69	C	33 (6 health)	—
186	20463	Washington	69	C	33 (6 health)	—
187	20468	Washington	69	C	33 (6 health)	—
188	20469	Washington	69	C	33 (6 health)	—
189	20472	Washington	69	C	33 (6 health)	—
190	20500	Washington	69	C	33 (6 health)	—
191	20501	Washington	69	C	33 (6 health)	—
192	20502	Washington	69	C	33 (6 health)	—
193	20503	Washington	69	C	33 (6 health)	—
194	20504	Washington	69	C	33 (6 health)	—
195	20505	Washington	69	C	33 (6 health)	—
196	20506	Washington	69	C	33 (6 health)	—
197	20507	Washington	69	C	33 (6 health)	—
198	20508	Washington	69	C	33 (6 health)	—
199	20509	Washington	69	C	33 (6 health)	—
200	20510	Washington	69	C	33 (6 health)	—
201	20511	Washington	69	C	33 (6 health)	—
202	20521	Washington	69	C	33 (6 health)	—
203	20522	Washington	69	C	33 (6 health)	—
204	20523	Washington	69	C	33 (6 health)	—
205	20524	Washington	69	C	33 (6 health)	—
206	20525	Washington	69	C	33 (6 health)	—
207	20526	Washington	69	C	33 (6 health)	—
208	20527	Washington	69	C	33 (6 health)	—
209	20528	Washington	69	C	33 (6 health)	—
210	20529	Washington	69	C	33 (6 health)	—
211	20531	Washington	69	C	33 (6 health)	—
212	20532	Washington	69	C	33 (6 health)	—
213	20533	Washington	69	C	33 (6 health)	—
214	20534	Washington	69	C	33 (6 health)	—
215	20535	Washington	69	C	33 (6 health)	—
216	20536	Washington	69	C	33 (6 health)	—
217	20537	Washington	69	C	33 (6 health)	—
218	20538	Washington	69	C	33 (6 health)	—
219	20539	Washington	69	C	33 (6 health)	—
220	20540	Washington	69	C	33 (6 health)	—
221	20541	Washington	69	C	33 (6 health)	—
222	20542	Washington	69	C	33 (6 health)	—
223	20543	Washington	69	C	33 (6 health)	—
224	20544	Washington	69	C	33 (6 health)	—
225	20546	Washington	69	C	33 (6 health)	—
226	20547	Washington	69	C	33 (6 health)	—
227	20548	Washington	69	C	33 (6 health)	—
228	20549	Washington	69	C	33 (6 health)	—
229	20551	Washington	69	C	33 (6 health)	—
230	20552	Washington	69	C	33 (6 health)	—
231	20553	Washington	69	C	33 (6 health)	—
232	20554	Washington	69	C	33 (6 health)	—
233	20555	Washington	69	C	33 (6 health)	—
234	20557	Washington	69	C	33 (6 health)	—
235	20558	Washington	69	C	33 (6 health)	—
236	20559	Washington	69	C	33 (6 health)	—
237	20560	Washington	69	C	33 (6 health)	—
238	20565	Washington	69	C	33 (6 health)	—
239	20566	Washington	69	C	33 (6 health)	—
240	20570	Washington	69	C	33 (6 health)	—
241	20571	Washington	69	C	33 (6 health)	—
242	20572	Washington	69	C	33 (6 health)	—
243	20573	Washington	69	C	33 (6 health)	—
244	20575	Washington	69	C	33 (6 health)	—
245	20576	Washington	69	C	33 (6 health)	—
246	20577	Washington	69	C	33 (6 health)	—
247	20578	Washington	69	C	33 (6 health)	—
248	20579	Washington	69	C	33 (6 health)	—
249	20580	Washington	69	C	33 (6 health)	—
250	20581	Washington	69	C	33 (6 health)	—
251	20585	Washington	69	C	33 (6 health)	—
252	20586	Washington	69	C	33 (6 health)	—
253	20590	Washington	69	C	33 (6 health)	—
254	20591	Washington	69	C	33 (6 health)	—
255	20593	Washington	69	C	33 (6 health)	—
256	20594	Washington	69	C	33 (6 health)	—
257	20597	Washington	69	C	33 (6 health)	—
258	20599	Washington	69	C	33 (6 health)	—
259	20001	Washington	67	C	33 (6 health)	$845K
260	20002	Washington	67	C	33 (6 health)	$814K
261	20008	Washington	67	C	33 (6 health)	$894K
262	20009	Washington	67	C	33 (6 health)	$728K
263	20010	Washington	67	C	33 (6 health)	$868K
264	20011	Washington	67	C	33 (6 health)	$722K
265	20012	Washington	67	C	33 (6 health)	$838K
266	20015	Washington	67	C	33 (6 health)	$1209K
267	20016	Washington	67	C	33 (6 health)	$1206K
268	20017	Washington	67	C	33 (6 health)	$686K
269	20018	Washington	67	C	33 (6 health)	$672K
270	20020	Washington	67	C	33 (6 health)	$443K
271	20007	Washington	62	C	33 (6 health)	$1203K
272	20019	Washington	62	C	33 (6 health)	$438K
273	20373	Naval Anacost Annex	50	D	0	—
274	20374	Washington Navy Yard	50	D	0	—
275	20376	Washington Navy Yard	50	D	0	—
276	20388	Washington Navy Yard	50	D	0	—
277	20391	Washington Navy Yard	50	D	0	—
278	20398	Washington Navy Yard	50	D	0	—
279	56901	Parcel Return Service	50	D	0	—
280	56915	Parcel Return Service	50	D	0	—
281	56920	Parcel Return Service	50	D	0	—
282	56933	Parcel Return Service	50	D	0	—
283	56944	Parcel Return Service	50	D	0	—
284	56972	Parcel Return Service	50	D	0	—

Recommended Buyer Guides for District of Columbia County

Editorial-only picks, screened against the EPA detections on file.

Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county

Deep Dive Reports

Detailed analysis for District of Columbia County, District of Columbia

💧

Water Quality

EPA violations, contaminant trends, and enforcement actions across the county

⚠️

Lead Risk

Lead exposure scores, housing age analysis, and LCR testing trends

🏠

Home Affordability

Remediation costs vs. home values, equity trap analysis by ZIP

$1,210 avg remediation

🌊

Flood Risk

FEMA flood zones, insurance claims, and flood risk data across the county

Overview

District of Columbia County in District of Columbia covers 284 ZIP codes with an average Home Safety Score of C (68/100).

272 of 284 ZIP codes have recorded EPA violations. 1632 health-based violations have been documented.

← Back to District of Columbia water quality report

Data Sources

Water quality: EPA Safe Drinking Water Information System (SDWIS)
Home values: U.S. Census Bureau ACS (median estimates by ZCTA)

Updated daily.

Frequently Asked Questions

Is water safe in District of Columbia County?

District of Columbia County receives a grade of C. Some ZIP codes have recorded violations and residents in affected areas may want to test their water.

How many water systems serve District of Columbia County?

District of Columbia County is served by 4 public water systems that supply drinking water to residents across 284 ZIP codes.

What is the biggest environmental risk in District of Columbia County?

The primary environmental risk factor in District of Columbia County is sea_level. This contributes to an estimated additional annual cost of $2,114 per homeowner.

How does District of Columbia County compare to District of Columbia?

District of Columbia County has an average water safety score of 68/100, which is above the District of Columbia state average of 68/100.

Explore More

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District of Columbia State Overview →