California Tap Water Quality Report

898 cities analyzed • 57,035,501 people served

Updated March 2026 • Data from EWG & EPA SDWIS

898

Cities Analyzed

8.9

Avg Above Guidelines

57,035,501

Total Population Served

Best Water Quality

Georgetown (0 above guidelines)

Most Concerns

Corona (25 above guidelines)

Most Common Contaminants in California

Contaminant	Found In	% of Cities
Haloacetic acids (HAA5) carcinogen	679 of 898	76%
Total trihalomethanes (TTHMs) carcinogen	613 of 898	68%
Nitrate carcinogen	602 of 898	67%
Manganese	578 of 898	64%
Fluoride	558 of 898	62%
Bromodichloromethane carcinogen	543 of 898	60%
Dibromochloromethane carcinogen	529 of 898	59%
Chloroform carcinogen	509 of 898	57%
Bromoform carcinogen	478 of 898	53%
Dibromoacetic acid	464 of 898	52%

City-by-City Water Quality Rankings

Ranked by number of contaminants above EWG health guidelines (most to fewest).

#	City	Detected	Above Guidelines	Above Legal	People Served
1	Corona	46	25	2	168,751
2	Pleasanton	43	23	2	79,871
3	Fresno	51	22	0	545,466
4	Anaheim	44	22	2	341,245
5	Lake Elsinore	42	22	1	165,586
6	Compton	35	22	0	74,877
7	Wildomar	42	22	0	4,026
8	Clovis	39	21	0	125,722
9	Dublin	41	21	2	98,776
10	Manteca	33	21	1	84,625
11	Lynwood	36	21	0	66,967
12	Livermore	41	21	2	35,672
13	Norwalk	45	21	1	17,790
14	La Habra Heights	34	21	2	5,682
15	Santa Ana	40	20	1	337,716
16	Garden Grove	41	20	1	174,226
17	Fullerton	42	20	1	141,874
18	Pacific Grove	37	20	0	92,450
19	Pico Rivera	38	20	2	40,600
20	La Crescenta	43	20	0	32,665
21	Santa Clarita	40	20	1	17,154
22	Villa Park	35	20	2	5,773
23	Irvine	38	19	0	468,941
24	Alhambra	40	19	0	204,393
25	Huntington Beach	33	19	0	201,000
26	Pomona	37	19	0	151,713
27	Temecula	35	19	0	144,088
28	Rialto	36	19	0	98,055
29	Santa Monica	30	19	0	93,076
30	Placentia	35	19	0	84,054
31	Newport Beach	31	19	0	68,572
32	Lathrop	36	19	1	35,080
33	Atascadero	38	19	2	30,457
34	San Fernando	29	19	0	23,946
35	Arroyo Grande	35	19	0	17,963
36	Nuevo	38	19	1	6,733
37	Perris	38	18	0	637,387
38	Orange	36	18	0	117,150
39	Azusa	33	18	0	110,044
40	Westminster	32	18	0	95,256
41	Simi Valley	33	18	0	94,738
42	Goleta	32	18	0	84,462
43	Buena Park	32	18	0	81,998
44	South Gate	36	18	2	76,443
45	Lodi	36	18	0	68,272
46	Paramount	31	18	0	55,200
47	Glendora	37	18	0	52,558
48	Delano	30	18	0	51,428
49	Camp Pendleton	35	18	1	45,000
50	Adelanto	28	18	0	39,930
51	Boulder Creek	35	18	0	21,145
52	Lomita	31	18	0	20,256
53	Altadena	32	18	0	16,126
54	Lindsay	31	18	0	12,659
55	Maywood	28	18	1	9,500
56	Solvang	30	18	0	6,126
57	Newhall	28	17	0	294,639
58	Burbank	33	17	0	105,451
59	Elmira	31	17	0	97,155
60	Inglewood	32	17	0	82,041
61	Tustin	38	17	2	66,600
62	Porterville	37	17	0	62,988
63	Santa Fe Springs	33	17	0	62,970
64	Cerritos	32	17	0	49,578
65	Arcadia	32	17	0	44,738
66	Moorpark	31	17	0	36,625
67	Ramona	29	17	0	35,135
68	Manhattan Beach	29	17	0	34,668
69	Montebello	33	17	2	26,554
70	South Pasadena	28	17	0	25,329
71	Norco	35	17	2	24,909
72	Shafter	30	17	0	21,036
73	Quartz Hill	28	17	0	19,100
74	Cudahy	29	17	2	14,000
75	Westlake Village	30	17	0	13,898
76	Big Bear City	27	17	0	12,738
77	La Canada Flintridge	27	17	0	10,070
78	West Covina	31	17	0	7,775
79	Moreno Valley	35	17	1	3,542
80	San Jose	32	16	0	1,934,171
81	Sacramento	36	16	1	520,746
82	El Monte	39	16	0	254,300
83	Rancho Cucamonga	29	16	0	202,248
84	Pasadena	31	16	0	170,950
85	Imperial Beach	33	16	0	106,000
86	Highland	26	16	0	103,758
87	Santa Barbara	35	16	1	98,420
88	Tracy	30	16	0	94,538
89	Carlsbad	30	16	0	92,865
90	Claremont	26	16	0	67,018
91	Rosemead	31	16	0	66,809
92	La Habra	25	16	0	63,118
93	Lakewood	26	16	0	63,066
94	Pittsburg	27	16	0	62,500
95	Fountain Valley	31	16	0	56,747
96	Montclair	26	16	0	56,422
97	San Clemente	25	16	0	51,545
98	Colton	29	16	1	46,525
99	Bellflower	29	16	1	46,300
100	Carmichael	25	16	0	41,193
101	Beverly Hills	35	16	0	40,856
102	Monrovia	29	16	2	37,787
103	Fallbrook	30	16	0	35,237
104	Paso Robles	27	16	0	31,221
105	Seal Beach	28	16	0	24,937
106	Corcoran	26	16	1	21,835
107	El Segundo	24	16	0	16,898
108	Nipomo	26	16	0	13,771
109	Signal Hill	33	16	0	11,795
110	Elizabeth Lake	23	16	0	1,790
111	Brisbane	30	16	0	1,471
112	Barstow	26	16	0	302
113	Prunedale	23	16	2	108
114	Thousand Oaks	25	15	0	640,000
115	Covina	22	15	1	369,059
116	Palmdale	21	15	0	286,142
117	Hawthorne	27	15	0	275,369
118	San Marcos	30	15	0	111,000
119	Ventura	27	15	0	110,763
120	Costa Mesa	27	15	0	110,000
121	Santa Maria	25	15	0	109,910
122	Torrance	28	15	0	106,183
123	Chino	28	15	0	84,560
124	Redlands	29	15	0	78,025
125	Chino Hills	24	15	0	77,964
126	Baldwin Park	30	15	0	68,714
127	Brentwood	30	15	0	64,342
128	San Dimas	26	15	0	56,426
129	Hemet	29	15	0	52,913
130	Yucaipa	31	15	0	51,900
131	Camarillo	35	15	0	46,848
132	Soquel	29	15	0	40,644
133	Truckee	23	15	0	36,730
134	Valley Center	28	15	0	29,708
135	Atwater	33	15	1	29,479
136	Vernon	29	15	0	28,000
137	Hollister	27	15	0	23,499
138	Patterson	28	15	0	23,304
139	Half Moon Bay	30	15	0	18,789
140	Ukiah	29	15	0	16,607
141	Carpinteria	26	15	0	15,996
142	California City	29	15	0	14,198
143	Avenal	22	15	0	13,819
144	Trabuco Canyon	30	15	0	13,659
145	Morro Bay	26	15	1	10,581
146	Crestline	25	15	0	10,030
147	Tehachapi	24	15	0	9,808
148	Guadalupe	21	15	0	8,352
149	Santa Ynez	24	15	0	7,022
150	Del Mar	33	15	0	3,929
151	Whittier	31	14	1	290,814
152	Palm Desert	28	14	0	270,000
153	Oxnard	20	14	0	240,000
154	San Bernardino	36	14	0	204,870
155	Concord	24	14	0	198,000
156	Chula Vista	27	14	0	189,371
157	Oceanside	30	14	0	173,048
158	Las Flores	18	14	0	164,604
159	Hayward	26	14	0	159,293
160	Jurupa Valley	36	14	0	133,292
161	Victorville	25	14	0	124,653
162	Santa Cruz	29	14	0	95,939
163	Redding	29	14	0	87,741
164	Calabasas	24	14	0	72,602
165	Tulare	28	14	0	70,733
166	Watsonville	31	14	0	65,231
167	Monterey Park	28	14	0	62,183
168	Gilroy	27	14	0	58,108
169	Palm Springs	22	14	0	57,507
170	Oakley	26	14	0	43,357
171	Ridgecrest	20	14	0	39,478
172	Foster City	26	14	0	36,556
173	Martinez	24	14	0	28,518
174	Lemoore	24	14	1	27,038
175	Rancho Santa Fe	31	14	0	21,539
176	Rosamond	25	14	0	17,516
177	Soledad	28	14	0	17,073
178	Olivehurst	25	14	0	16,595
179	La Palma	27	14	0	15,948
180	Mcfarland	24	14	0	15,506
181	Grover Beach	25	14	0	12,701
182	Kingsburg	23	14	0	12,380
183	Sonoma	23	14	0	11,725
184	Healdsburg	23	14	0	11,174
185	Sierra Madre	26	14	0	11,000
186	Susanville	22	14	0	8,641
187	Lake Arrowhead	27	14	2	7,008
188	Montara	28	14	0	5,298
189	Mojave	20	14	0	4,699
190	Bloomington	17	14	0	3,055
191	Terra Bella	23	14	0	2,656
192	Edwards AFB	26	14	0	2,577
193	Cedarpines Park	19	14	0	2,458
194	Boron	20	14	0	2,253
195	Clayton	24	14	0	549
196	Oakhurst	29	14	1	498
197	North Edwards	20	14	0	270
198	Chiriaco Summit	19	14	0	45
199	Burlingame	27	13	0	800,000
200	Long Beach	26	13	0	460,682
201	Sunnyvale	25	13	0	155,567
202	Escondido	23	13	0	137,941
203	Santa Clara	24	13	0	130,746
204	Fairfield	26	13	0	119,897
205	Merced	31	13	0	92,058
206	Encinitas	22	13	0	86,614
207	Ceres	20	13	0	48,706
208	Morgann Hill	24	13	0	47,374
209	Los Banos	23	13	0	46,639
210	Rohnert Park	23	13	0	42,484
211	Pacifica	26	13	0	38,546
212	Marina	26	13	0	36,214
213	Belmont	26	13	0	28,050
214	Loma Linda	28	13	0	24,791
215	El Verano	22	13	0	23,077
216	Millbrae	26	13	0	22,795
217	Taft	21	13	0	19,832
218	Arvin	26	13	1	19,669
219	Greenfield	27	13	0	18,967
220	San Jacinto	23	13	0	18,950
221	29 Palms	22	13	0	17,033
222	Whitethorn	18	13	0	12,133
223	Blythe	21	13	0	9,890
224	La Canada	17	13	0	9,300
225	Pismo Beach	19	13	0	8,036
226	Los Altos Hills	23	13	0	6,822
227	Ojai	28	13	0	6,100
228	Cambria	19	13	0	5,532
229	Moffett Field	24	13	0	5,300
230	Running Springs	16	13	0	5,268
231	Needles	14	13	0	5,183
232	China Lake	18	13	0	4,800
233	Littlerock	15	13	0	2,985
234	Green Valley Lake	18	13	0	2,962
235	Frazier Park	17	13	0	2,691
236	San Miguel	19	13	0	2,600
237	Twin Peaks	18	13	0	2,534
238	Santa Nella	18	13	0	2,211
239	Lake Arrowhead Ca 92352	18	13	0	745
240	Carmel	23	13	0	584
241	Wilmington	17	13	1	99
242	Paicines	20	13	0	25
243	Riverside	25	12	0	300,488
244	Spring Valley	18	12	0	227,957
245	Bakersfield	21	12	0	185,000
246	Vallejo	20	12	0	126,090
247	Downey	28	12	2	109,946
248	Hesperia	26	12	0	100,324
249	Santee	19	12	0	88,963
250	Mountain View	23	12	0	81,756
251	Citrus Heights	24	12	0	66,815
252	Novato	18	12	0	61,683
253	Petaluma	24	12	0	61,304
254	Lincoln	22	12	0	51,252
255	Poway	24	12	0	49,779
256	San Bruno	19	12	0	46,085
257	Lompoc	22	12	0	41,079
258	Laguna Beach	21	12	0	34,724
259	East Palo Alto	27	12	0	29,519
260	Windsor	16	12	0	28,397
261	Brawley	20	12	0	26,928
262	Sanger	23	12	0	26,241
263	Imperial	20	12	0	21,347
264	American Canyon	27	12	0	20,990
265	Temescal Valley	24	12	0	20,526
266	Cutten	18	12	0	19,726
267	Lamont	21	12	0	19,057
268	Twentynine Palms	22	12	0	18,795
269	Coalinga	20	12	0	17,277
270	Discovery Bay	25	12	0	16,790
271	Livingston	21	12	0	14,894
272	Big Bear Lake	23	12	0	12,609
273	Hillsborough	25	12	0	11,387
274	Scotts Valley	30	12	0	10,709
275	Calimesa	16	12	0	10,061
276	Dos Palos	17	12	1	7,452
277	Cotati	17	12	0	7,360
278	Huron	18	12	1	7,306
279	Los Osos	26	12	0	7,086
280	Cutler	15	12	0	6,200
281	Helendale	20	12	3	6,050
282	Point Mugu	20	12	0	3,500
283	Pixley	16	12	0	2,772
284	Sky Forest	18	12	0	2,644
285	Beale Afb	15	12	0	2,400
286	Cayucos	19	12	0	2,369
287	San Juan Bautista	18	12	0	2,335
288	Strathmore	18	12	0	1,690
289	Lebec	13	12	0	1,379
290	Campo	17	12	0	670
291	Redwood Estates	20	12	0	346
292	Usag Fort Hunter Liggett	18	12	0	258
293	Kenwood	20	12	0	208
294	Romoland	15	12	0	198
295	Monterey	20	12	1	136
296	Placida	12	12	0	44
297	Newberry Springs	15	12	2	40
298	Armona	15	12	0	0
299	Buellton	16	11	0	646,441
300	Apple Valley	14	11	0	316,866
301	Santa Rosa	20	11	0	175,775
302	Laguna Hills	17	11	0	170,236
303	Roseville	22	11	0	149,859
304	Vista	19	11	0	132,838
305	Antioch	23	11	0	115,074
306	Daly City	19	11	0	108,599
307	Walnut	21	11	0	100,449
308	Milpitas	18	11	0	77,961
309	Rowland Heights	20	11	0	54,660
310	Lake Forest	19	11	0	47,911
311	San Luis Obispo	18	11	0	47,708
312	Brea	18	11	0	47,589
313	El Centro	24	11	0	44,158
314	Desert Hot Springs	17	11	0	43,223
315	Port Hueneme	14	11	0	41,679
316	Calexico	22	11	0	40,357
317	Fair Oaks	19	11	0	35,377
318	Santa Paula	20	11	0	30,759
319	Yucca Valley	19	11	0	26,032
320	Mountain House	21	11	0	24,040
321	Wasco	20	11	0	22,608
322	South Lake Tahoe	26	11	0	21,414
323	Grand Terrace	22	11	0	19,503
324	Pinedale	22	11	0	16,735
325	Huntington Park	19	11	0	16,180
326	Fort Irwin	20	11	0	16,000
327	Vandenberg AFB	20	11	0	14,971
328	Parlier	17	11	0	14,576
329	Newman	22	11	0	12,351
330	Exeter	22	11	0	11,169
331	Oak View	24	11	0	11,005
332	Shasta Lake	16	11	0	10,657
333	Rio Vista	24	11	0	10,489
334	Clearlake	16	11	0	9,510
335	Orosi	13	11	0	8,300
336	Woodlake	16	11	0	7,950
337	Oceano	14	11	0	7,601
338	Joshua Tree	14	11	0	7,414
339	Willits	15	11	0	6,175
340	Avalon	22	11	0	4,096
341	San Francisco	14	11	0	3,500
342	La Grange	18	11	0	3,240
343	Aromas	20	11	0	2,988
344	Laytonville	13	11	0	2,000
345	Avila Beach	18	11	0	1,630
346	Bolinas	16	11	0	1,483
347	Lower Lake	17	11	0	1,355
348	Green Valley	15	11	0	1,190
349	Kettleman City	20	11	0	1,136
350	Felton	24	11	0	1,067
351	Pauma Valley	16	11	0	899
352	La Honda	16	11	0	832
353	Inyokern	15	11	0	805
354	Stinson Beach	12	11	0	583
355	Three Rivers	15	11	0	560
356	Llano	12	11	0	445
357	Kernville	18	11	2	336
358	Casitas Springs	24	11	0	238
359	Pescadero	21	11	0	150
360	Tampa	12	11	0	108
361	Sausalito	20	11	0	75
362	Gorman	13	11	0	70
363	Graton	14	11	0	45
364	Darwin	15	11	1	40
365	Nicasio	15	11	1	31
366	Helm	14	11	0	25
367	Fremont	20	10	0	344,855
368	Glendale	26	10	0	201,334
369	Corte Madera	19	10	0	193,937
370	Auburn	16	10	0	89,008
371	Napa	19	10	0	85,005
372	Indio	21	10	0	82,668
373	Turlock	18	10	0	72,682
374	Madera	17	10	0	66,172
375	Hanford	22	10	0	62,127
376	Benicia	22	10	0	28,000
377	Oroville	15	10	0	22,727
378	Marysville	17	10	0	21,654
379	Grass Valley	15	10	0	17,154
380	Fillmore	15	10	0	16,419
381	Mendota	19	10	0	11,404
382	Chico	21	10	0	10,900
383	Sonora	18	10	0	10,814
384	Live Oak	14	10	1	9,285
385	Cloverdale	13	10	0	8,869
386	Firebaugh	20	10	1	7,619
387	Heber	19	10	0	6,979
388	Fort Bragg	14	10	0	6,970
389	Paradise	17	10	0	6,518
390	Holtville	16	10	0	6,355
391	Guerneville	13	10	0	6,000
392	Yountville	12	10	0	3,436
393	Idyllwild	16	10	0	2,963
394	Seaside	17	10	0	2,800
395	Talmage	13	10	0	2,554
396	Tipton	13	10	0	2,543
397	Westmorland	17	10	0	2,202
398	Poplar	11	10	0	2,200
399	Devore	13	10	0	2,009
400	Midway City	16	10	0	2,000
401	Mariposa	13	10	0	2,000
402	Trona	13	10	0	1,818
403	Seeley	18	10	0	1,729
404	Los Alamos	15	10	0	1,534
405	Springville	15	10	0	1,500
406	Inverness	13	10	0	1,445
407	Gerber	14	10	0	1,200
408	Sea Ranch	13	10	0	1,160
409	Trinidad	12	10	0	1,072
410	Garberville	10	10	0	913
411	Tranquillity	15	10	0	807
412	San Martin	14	10	0	773
413	Alpine	10	10	0	560
414	San Simeon	14	10	0	462
415	Bridgeport	15	10	1	450
416	Edison	14	10	2	438
417	Coarsegold	13	10	0	370
418	Muir Beach	14	10	0	336
419	Johannesburg	12	10	1	303
420	Paskenta	11	10	0	244
421	Lemon Cove	10	10	2	109
422	Lake Oswego	14	10	0	104
423	Loomis	16	10	0	84
424	Bodega	14	10	0	77
425	Westport	13	10	0	70
426	Dillon Beach	14	10	0	66
427	Loma Mar	14	10	0	65
428	Valley Ford	14	10	2	61
429	Auberry	14	10	1	40
430	Agoura Hills	17	10	0	35
431	Blue Jay	10	10	0	25
432	Le Grand	14	10	0	0
433	Elk Creek	12	10	0	0
434	Los Angeles	24	9	0	3,868,811
435	Yuba City	15	9	0	75,322
436	Palo Alto	16	9	0	67,973
437	West Sacramento	15	9	0	53,355
438	Elk Grove	22	9	0	42,556
439	Stanford	16	9	0	32,235
440	Salinas	22	9	0	30,103
441	Vacaville	16	9	0	29,530
442	Eureka	14	9	0	27,078
443	Dinuba	16	9	0	26,913
444	Reedley	16	9	0	25,227
445	Arcata	14	9	0	20,359
446	Menlo Park	15	9	0	19,297
447	Mckinleyville	13	9	0	16,900
448	Orangevale	12	9	0	16,861
449	Crescent City	12	9	0	16,711
450	Dixon	18	9	0	11,784
451	San Andreas	16	9	0	11,545
452	Orange Cove	12	9	0	9,780
453	Waterford	12	9	0	8,788
454	Mammoth Lakes	20	9	0	8,234
455	Templeton	16	9	0	8,011
456	Sebastopol	15	9	0	7,522
457	Escalon	12	9	0	7,362
458	Gridley	14	9	0	7,356
459	Castroville	15	9	1	6,897
460	Hidden Valley Lake	11	9	0	6,235
461	Lakeport	15	9	0	4,762
462	Kelseyville	14	9	0	4,360
463	Forestville	10	9	0	4,150
464	Nevada City	12	9	0	3,148
465	Nice	16	9	0	2,731
466	Aptos	10	9	0	2,715
467	Gualala	11	9	0	2,593
468	Smith River	9	9	0	2,568
469	Sutter Creek	13	9	0	2,402
470	Pine Valley	12	9	0	1,645
471	Blue Lake	13	9	0	1,245
472	Valley Springs	12	9	0	900
473	River Pines	10	9	0	574
474	Clio	9	9	0	540
475	Los Gatos	14	9	0	500
476	Warner Springs	14	9	0	443
477	Palo Verde	11	9	0	410
478	Arnold	16	9	0	361
479	Coleville	11	9	0	325
480	San Lucas	11	9	0	315
481	Bodega Bay	10	9	0	188
482	Mendocino	9	9	0	160
483	Dana Point	11	9	0	125
484	Manchester	13	9	0	114
485	Death Valley	12	9	0	88
486	Woodside	12	9	0	66
487	Point Reyes	11	9	0	55
488	Corralitos	12	9	0	54
489	Palomar Mountain	15	9	0	50
490	Dunlap	13	9	0	33
491	Moss Landing	11	9	0	32
492	Mount Hamilton	13	9	0	28
493	Clearlake Oak	14	9	0	0
494	Arbuckle	13	9	0	0
495	Boonville	12	9	0	0
496	Bass Lake	14	9	0	0
497	Placerville	17	8	0	131,527
498	Redwood City	14	8	0	89,037
499	Folsom	13	8	0	75,728
500	Davis	20	8	0	67,217
501	Beaumont	16	8	0	49,241
502	Coachella	17	8	0	42,554
503	Banning	20	8	0	31,179
504	Granite Bay	11	8	0	28,971
505	Galt	18	8	0	26,536
506	Phelan	18	8	0	23,585
507	Oakdale	18	8	0	23,235
508	Chowchilla	20	8	0	13,576
509	South San Francisco	11	8	0	13,486
510	Delhi	11	8	0	7,784
511	Earlimart	13	8	0	7,679
512	Royal Oaks	17	8	0	6,500
513	Hilmar	13	8	0	5,504
514	St. Helena	12	8	0	5,386
515	Ivanhoe	12	8	0	4,347
516	Tahoe Vista	9	8	0	4,214
517	Weaverville	12	8	1	3,308
518	Twain Harte	13	8	0	2,378
519	Bradley	14	8	0	2,181
520	Lost Hills	13	8	0	1,726
521	Montague	10	8	0	1,495
522	Mi Wuk Village	12	8	0	1,069
523	Sultana	9	8	0	779
524	Graeagle	9	8	0	737
525	New Cuyama	11	8	1	700
526	Point Arena	9	8	0	667
527	Jacumba	9	8	0	561
528	Sana Barbara	10	8	0	550
529	Fulton	9	8	0	448
530	Tres Pinos	14	8	0	350
531	Ferndale	8	8	0	333
532	June Lake	12	8	0	310
533	Korbel	9	8	0	250
534	Hume	12	8	0	210
535	San Juan Capistrano	11	8	0	190
536	Jenner	13	8	0	190
537	Cazadero	9	8	0	150
538	Carmel Valley	9	8	0	129
539	Big Sur	8	8	0	129
540	Omaha	11	8	0	83
541	Encino	11	8	1	82
542	Crows Landing	10	8	0	70
543	Platina	8	8	0	55
544	Gaviota	10	8	0	54
545	Castro Valley	9	8	0	50
546	City Of Angels	11	8	0	0
547	Kerman	15	7	1	16,995
548	Anderson	16	7	0	11,147
549	Winton	11	7	0	9,500
550	Gonzales	20	7	0	8,576
551	Gustine	13	7	0	5,945
552	Meadow Vista	8	7	0	5,250
553	Jackson	8	7	0	4,786
554	Murphys	9	7	0	4,774
555	Borrego Springs	11	7	0	3,429
556	Rio Dell	7	7	0	3,300
557	Cabazon	10	7	0	2,271
558	Portola	8	7	0	2,100
559	Julian	9	7	0	1,768
560	Mount Hermon	10	7	0	1,650
561	Shasta	9	7	0	1,584
562	Willow Creek	9	7	0	1,298
563	Redway	9	7	0	1,207
564	Camp Meeker	9	7	0	1,171
565	Pine Grove	10	7	0	1,141
566	Loleta	7	7	0	937
567	Friant	12	7	0	772
568	Scotia	8	7	0	681
569	Weldon	10	7	0	632
570	Lake Isabella	11	7	0	500
571	Weott	7	7	0	456
572	Salyer	7	7	0	330
573	Myers Flat	8	7	0	330
574	Elk	10	7	0	280
575	Colusa	7	7	0	250
576	Cold Springs	10	7	0	168
577	Tuolumne	10	7	0	154
578	Los Olivos	15	7	0	129
579	Kirkwood	15	7	0	101
580	Duncans Mills	7	7	0	82
581	Coyote	10	7	0	68
582	Orinda	8	7	0	30
583	Kyburz	8	7	0	30
584	Cantil	10	7	0	19
585	Alderpoint	7	7	0	0
586	Brownsville	11	7	0	0
587	Gasquet	9	7	0	0
588	San Diego	15	6	0	3,276,208
589	Stockton	12	6	0	364,624
590	Ripon	7	6	0	212,000
591	Rancho Cordova	20	6	0	47,060
592	Rio Linda	13	6	0	15,404
593	La Puente	15	6	0	8,213
594	Yreka	7	6	0	7,746
595	Williams	9	6	0	5,255
596	Esparto	10	6	0	3,710
597	Jamestown	11	6	0	2,230
598	Lancaster	9	6	1	1,500
599	Del Rey	6	6	0	1,413
600	Fortuna	6	6	0	1,412
601	Ione	7	6	0	1,303
602	Yosemite Np	7	6	0	1,000
603	Baker	10	6	0	1,000
604	Orleans	7	6	0	636
605	Bear Valley	9	6	0	625
606	Mount Baldy	9	6	0	600
607	Dutch Flat	8	6	0	350
608	Hornbrook	12	6	0	280
609	Lakehead	6	6	0	264
610	Applegate	9	6	0	250
611	Colfax	8	6	0	250
612	Alamo	8	6	0	201
613	Floriston	7	6	0	110
614	Redwood Valley	9	6	0	90
615	Hughson	7	6	1	50
616	Big Creek	9	6	0	38
617	Snelling	11	6	0	36
618	Hickman	9	6	0	26
619	Biggs	11	6	0	0
620	Albion	7	6	0	0
621	Alpaugh	8	6	0	0
622	Burnt Ranch	7	6	0	0
623	Wheatland	9	6	0	0
624	Cassel	6	6	0	0
625	La Verne	10	5	0	18,606,473
626	Oakland	13	5	0	1,430,200
627	Riverbank	15	5	0	24,834
628	Red Bluff	13	5	0	14,076
629	Farmersville	14	5	0	10,397
630	Fowler	9	5	0	7,100
631	Keyes	7	5	0	5,672
632	Planada	8	5	0	4,500
633	Caruthers	6	5	1	2,503
634	Richgrove	6	5	1	1,617
635	Laton	5	5	0	1,551
636	Los Molinos	8	5	0	1,450
637	Herlong	9	5	0	831
638	Daggett	7	5	1	795
639	Lucerne Valley	8	5	0	726
640	Ludlow	8	5	2	500
641	La Selva Beach	12	5	0	400
642	Chandler	10	5	0	325
643	Thermal	8	5	1	316
644	Phillipsville	10	5	0	300
645	Casmalia	11	5	0	234
646	Calistoga	6	5	0	200
647	San Mateo	13	5	1	125
648	Danville	8	5	0	120
649	Mt. Hamilton	8	5	0	110
650	Keene	10	5	0	80
651	Newcastle	6	5	0	24
652	Pinecrest	6	5	0	10
653	Ontario	7	4	0	376,341
654	Lakeside	11	4	0	277,418
655	Bermuda Dunes	13	4	0	8,948
656	Orland	12	4	0	8,252
657	Winters	9	4	0	7,115
658	Arrowbear Lake	6	4	0	1,396
659	Knights Landing	7	4	0	944
660	Madison	8	4	0	876
661	Saugus	5	4	0	535
662	Angelus Oaks	6	4	0	450
663	Occidental	4	4	0	383
664	Blairsden	5	4	1	334
665	Valencia	6	4	0	211
666	Rancho Mission Viejo	11	4	0	210
667	Los Altos	5	4	0	200
668	North Fork	9	4	2	200
669	Alpine Meadows	8	4	0	200
670	Potrero	9	4	1	200
671	Camas	9	4	0	168
672	Acampo	6	4	2	153
673	Hercules	6	4	0	151
674	Walnut Creek	6	4	0	150
675	Ocotillo	6	4	0	150
676	Corral De Tierra	7	4	0	92
677	Morgan Hill	11	4	0	80
678	Aguanga	8	4	1	75
679	Wofford Heights	8	4	0	68
680	Miramonte	6	4	0	60
681	Zamora	5	4	0	50
682	Winterhaven	7	4	0	50
683	Suisun City	9	4	0	49
684	Mi Wuk	4	4	0	34
685	Yermo	7	4	0	34
686	Artois	6	4	0	0
687	Denair	6	4	0	0
688	Upland	9	3	0	78,891
689	San Joaquin	7	3	0	4,060
690	Bishop	7	3	0	3,819
691	Cottonwood	8	3	0	3,329
692	Sutter	5	3	0	2,904
693	Weed	5	3	0	2,790
694	Carnelian Bay	7	3	0	2,593
695	Lockeford	7	3	0	2,500
696	Hayfork	5	3	0	2,324
697	Independence	5	3	0	1,835
698	Linden	4	3	0	1,784
699	Maxwell	6	3	0	1,175
700	Upper Lake	4	3	0	989
701	Mineral	5	3	0	634
702	Ducor	3	3	0	616
703	Lytle Creek	4	3	0	475
704	Tehama	7	3	0	435
705	San Leandro	6	3	0	420
706	Desert Center	4	3	0	350
707	Larkspur	6	3	0	316
708	Billings	4	3	0	300
709	Greenbrae	7	3	0	300
710	Standard	5	3	0	252
711	West Hollyhood	6	3	0	250
712	Ballico	6	3	0	238
713	Yorba Linda	4	3	0	180
714	Elverta	4	3	0	166
715	Hopewell	5	3	0	135
716	Agua Dulce	5	3	0	109
717	Halcyon	3	3	1	105
718	Volcano	6	3	0	103
719	Guatay	6	3	1	100
720	Plumas Lake	6	3	0	100
721	Dunnigan	6	3	0	95
722	Moraga	3	3	1	93
723	Cedar Glen	4	3	0	80
724	Rancho Sante Fe	4	3	0	80
725	Mather	3	3	0	67
726	Canyon	7	3	0	66
727	Orcutt	6	3	0	66
728	Rancho Palos Verdes	6	3	1	65
729	Chualar	3	3	0	45
730	Wishon	4	3	1	42
731	Twain	3	3	0	32
732	Selma	3	3	0	25
733	Shoshone	5	3	0	0
734	Fiddletown	4	3	0	0
735	Biola	7	3	0	0
736	Butte City	5	3	0	0
737	Bieber	4	3	1	0
738	Downieville	5	3	0	0
739	Modesto	3	2	0	218,790
740	Woodland	3	2	0	129,820
741	Tahoe City	5	2	0	5,661
742	Riverdale	4	2	0	3,573
743	Alturas	5	2	0	2,715
744	Lake Almanor	4	2	0	1,874
745	Westwood	3	2	0	1,662
746	Loyalton	3	2	0	983
747	Big Pine	3	2	0	940
748	Angwin	3	2	0	758
749	Visalia	2	2	0	694
750	Crescent Mills	4	2	0	630
751	Miranda	2	2	0	492
752	Shingletoown	3	2	0	475
753	Bodfish	6	2	0	465
754	Princeton	5	2	0	382
755	Orick	2	2	0	346
756	La Quinta	2	2	1	340
757	Washington	3	2	0	330
758	Mentone	3	2	0	315
759	Grimes	3	2	1	305
760	Glenhaven	2	2	0	300
761	Penn Valley	2	2	0	300
762	Bountiful	4	2	0	274
763	Farmington	4	2	0	270
764	Anza	3	2	0	250
765	Klamath	2	2	0	200
766	Bedford	2	2	0	200
767	Ridgefield	3	2	0	181
768	Crowley Lake	3	2	0	175
769	Yuma	6	2	0	151
770	King City	6	2	0	150
771	Olancha	4	2	0	132
772	Lockwood	6	2	0	128
773	Wilton	3	2	0	118
774	Norden	5	2	1	115
775	San Marino	3	2	0	104
776	Mt Laguna	6	2	0	100
777	Greeley Hill	3	2	0	86
778	Canby	4	2	0	82
779	Lake Of The Woods	5	2	0	82
780	Eugene	4	2	0	80
781	Somerset	4	2	0	75
782	Redmond	4	2	0	70
783	Little Valley	3	2	0	70
784	Lone Pine	4	2	0	70
785	Groveland	3	2	0	59
786	Soulsbyville	3	2	0	59
787	Pleasant Hill	2	2	0	53
788	Ben Lomond	3	2	0	53
789	Glen Ellen	3	2	0	37
790	Piedra	2	2	0	36
791	Badger	5	2	0	33
792	Tujunga	4	2	0	25
793	Fawnskin	2	2	0	7
794	Calpine	2	2	0	0
795	Clipper Mills	6	2	0	0
796	Durham	3	2	0	0
797	Rancho Murieta	2	1	0	5,874
798	Represa	2	1	0	4,730
799	Quincy	4	1	0	4,300
800	Mt. Shasta	1	1	0	3,642
801	Homewood	3	1	0	1,351
802	Olympic Valley	3	1	0	1,165
803	Forest Falls	1	1	0	995
804	North Highlands	2	1	0	700
805	Cobb	1	1	0	693
806	Fort Jones	1	1	0	675
807	Bethel Island	1	1	0	644
808	Cedarville	1	1	0	600
809	Gilman Hot Springs	3	1	0	500
810	Duncan Mills	1	1	0	448
811	Middletown	1	1	0	373
812	Mt. Baldy	3	1	0	350
813	Soda Springs	4	1	0	310
814	Palo Cedro	1	1	0	300
815	Santa Ysabel	6	1	0	300
816	Geyserville	2	1	0	290
817	Grenada	2	1	0	289
818	Shaver Lake	6	1	1	250
819	Penngrove	3	1	0	237
820	Lee Vining	2	1	0	222
821	Jamul	2	1	0	219
822	El Dorado Hills	1	1	0	178
823	Silverdale	2	1	0	158
824	Reno	4	1	0	151
825	Isleton	4	1	1	150
826	Corning	1	1	0	140
827	Bethel Island Rd	1	1	0	140
828	Honolulu	3	1	0	130
829	Henderson	2	1	0	124
830	Forest Ranch	2	1	0	119
831	Copperopolis	2	1	0	100
832	Valyermo	4	1	0	100
833	San Ramon	2	1	0	100
834	Columbia	3	1	0	95
835	Courtland	2	1	1	90
836	North San Juan	4	1	0	90
837	Nelson	4	1	0	81
838	Walnut Grove	4	1	0	80
839	Woodbridge	5	1	0	75
840	Markleeville	1	1	0	70
841	Muphys	2	1	0	67
842	Macdoel	2	1	0	60
843	Angels Camp	1	1	0	60
844	Oregon House	2	1	0	60
845	Dobbins	3	1	0	60
846	Vinton	2	1	0	53
847	Rocklin	1	1	0	50
848	Spreckels	1	1	0	50
849	Plymouth	3	1	0	49
850	Shingle Springs	1	1	0	28
851	Buttonwillow	3	1	0	26
852	Butte Meadows	2	1	0	25
853	Prather	3	1	0	25
854	Vina	2	1	0	25
855	Birds Landing	2	1	1	25
856	Lewiston	2	1	0	19
857	Bridgeville	4	1	0	0
858	Sierraville	1	1	0	0
859	Berry Creek	1	1	0	0
860	Fall River Mills	3	1	0	0
861	Alleghany	1	1	0	0
862	Georgetown	4	0	0	9,409
863	Chester	2	0	0	2,145
864	Dunsmuir	0	0	0	1,707
865	Mccloud	1	0	0	1,300
866	Happy Camp	0	0	0	1,100
867	Grizzly Flats	1	0	0	1,093
868	Tulelake	1	0	0	966
869	Dorris	0	0	0	887
870	Shingletown	1	0	0	750
871	Eldorado Hills	0	0	0	750
872	Trinity Center	2	0	0	729
873	Saratoga	2	0	0	450
874	Paynes Creek	1	0	0	412
875	Mountain Center	0	0	0	232
876	Cherry Valley	0	0	0	210
877	Camptonville	1	0	0	180
878	Knights Ferry	2	0	0	168
879	Toms Place	0	0	0	150
880	Foresthill	1	0	0	150
881	Freedom	2	0	0	118
882	West Point	0	0	0	99
883	Long Barn	2	0	0	97
884	Callahan	1	0	0	70
885	Lake Hughes	0	0	0	57
886	Forsest Ranch	0	0	0	55
887	Greenville	1	0	0	54
888	66 Fir Tree Ct.	2	0	0	40
889	Railroad Flat	0	0	0	30
890	Woody	0	0	0	26
891	French Camp	0	0	0	26
892	Milford	0	0	0	25
893	Old Station	1	0	0	25
894	Tomales	2	0	0	25
895	Glennville	4	0	0	0
896	San Ardo	3	0	0	0
897	Burney	1	0	0	0
898	Emigrant Gap	2	0	0	0

Recommended Filtration for California

Based on the most common contaminants found across California (Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), Nitrate), we recommend a reverse osmosis system or high-quality carbon block filter to remove disinfection byproducts and their precursors.

Echo RO System

Removes up to 99.9% of contaminants. The gold standard for drinking water in California homes.

View RO Systems

Echo Whole-Home Filter

Protect every tap in your home from chlorine, VOCs, and disinfection byproducts.

View Whole-Home Filters

Echo Hydrogen Water Flask

Once your water is clean, supercharge it with molecular hydrogen for antioxidant and anti-inflammatory benefits.

Shop Hydrogen Flask

Frequently Asked Questions

Is California tap water safe to drink?

Water quality varies significantly across California. Of the 898 cities analyzed, the average city has 8.9 contaminants above EWG health guidelines. The best water quality was found in Georgetown. We recommend checking your specific city's report for detailed information.

What city has the best water in California?

Based on our analysis, Georgetown has the fewest contaminants above EWG health guidelines in California, with 0 above guideline levels.

What city has the worst water in California?

Based on our analysis, Corona has the most contaminants above EWG health guidelines in California, with 25 above guideline levels.

What's the best water filter for California residents?

For most California households, we recommend a reverse osmosis (RO) system for drinking water and a whole-home filter for showers and baths. The specific recommendation depends on your city's contaminant profile — check your city's report for personalized guidance.

National Water Quality Reports

Data sources: Environmental Working Group (EWG) Tap Water Database, U.S. EPA Safe Drinking Water Information System (SDWIS)

Last updated: March 2026

Methodology: Contaminant levels are compared against both EPA legal limits (Maximum Contaminant Levels) and EWG health guidelines, which are often stricter and based on the latest scientific research.

California Water Quality Report (2026)