Strontium Contamination

Strontium in California Drinking Water

Ranked by max strontium detected (µg/L) · UCMR 3 data (2013–2015) · Data from EPA SDWIS & UCMR

333

Cities Tested

Over HRL

% Over HRL

712.5 µg/L

State Avg

▼ 0% vs national

vs National

620

Health Violations

Analysis

Strontium in California: what the data shows

California has 333 cities with strontium data from the EPA's UCMR 3 program (2013–2015). Strontium was detected above the 1,500 µg/L EPA health reference level in 19 of those cities. The state average max detected level is 712.5 µg/L. Strontium occurs naturally in groundwater, particularly in areas with limestone and dolomite geology. It can also enter water from industrial waste and mining operations. There is no federal MCL for strontium, but the EPA established a health reference level (HRL) of 1,500 µg/L. Long-term exposure to strontium above the HRL may affect bone health, particularly in children, by substituting for calcium in developing bones. Reverse osmosis and ion exchange systems are effective at removing strontium from drinking water.

Comparison

Cities exceeding 1,500 µg/L EPA HRL (no MCL)

California

19 of 333 cities

← = Exactly at national rate

National avg

247 of 4292 cities

City Map

Strontium data across California

Each dot is a city with UCMR 3 strontium testing data. Cities where strontium exceeds the 1,500 µg/L EPA health reference level are highlighted. Size reflects population served.

Worst Offenders

Top 10 cities by strontium level in California

Highest Strontium levels (µg/L)

All Cities

All California cities ranked by strontium level

#	City	Level	Over HRL?	Violations	Grade
1	Patterson	3200.0 µg/L	Over HRL	35	B+
2	San Dimas	2650.0 µg/L	Over HRL	6	B-
3	Downey	2400.0 µg/L	Over HRL	14	B
4	Blythe	2400.0 µg/L	Over HRL	143	D
5	Newhall	2200.0 µg/L	Over HRL	1	B+
6	Tracy	2100.0 µg/L	Over HRL	45	C
7	Los Banos	2100.0 µg/L	Over HRL	29	B
8	Fillmore	2100.0 µg/L	Over HRL	13	B-
9	Newman	2100.0 µg/L	Over HRL	3	A-
10	Palm Desert	2000.0 µg/L	Over HRL	12	C+
11	Santa Barbara	1900.0 µg/L	Over HRL	52	F
12	Modesto	1800.0 µg/L	Over HRL	76	D
13	Ceres	1800.0 µg/L	Over HRL	129	F
14	Lindsay	1800.0 µg/L	Over HRL	240	F
15	Imperial	1700.0 µg/L	Over HRL	36	C+
16	Ventura	1600.0 µg/L	Over HRL	21	D+
17	Goleta	1600.0 µg/L	Over HRL	11	B
18	Point Mugu	1600.0 µg/L	Over HRL	11	A-
19	Carmel Valley	1520.0 µg/L	Over HRL	45	C+
20	Pleasanton	1500.0 µg/L	No	3	B-
21	Brentwood	1500.0 µg/L	No	91	F
22	El Centro	1500.0 µg/L	No	14	C-
23	San Jose	1400.0 µg/L	No	142	F
24	Hawthorne	1400.0 µg/L	No	3	B
25	Manteca	1400.0 µg/L	No	39	B-
26	Hollister	1400.0 µg/L	No	132	F
27	Moorpark	1400.0 µg/L	No	1	A-
28	Rancho Cordova	1300.0 µg/L	No	115	F
29	La Habra	1300.0 µg/L	No	0	A-
30	Fallbrook	1300.0 µg/L	No	3	A
31	Santa Paula	1300.0 µg/L	No	5	A-
32	Brawley	1300.0 µg/L	No	5	A-
33	Anaheim	1280.0 µg/L	No	8	C+
34	Huntington Beach	1240.0 µg/L	No	5	C-
35	Alhambra	1200.0 µg/L	No	7	A-
36	Glendale	1200.0 µg/L	No	0	A-
37	Temecula	1200.0 µg/L	No	12	C+
38	Oceanside	1200.0 µg/L	No	2	A-
39	Rancho Santa Margarita	1200.0 µg/L	No	0	A
40	Torrance	1200.0 µg/L	No	0	A-
41	Camarillo	1200.0 µg/L	No	4	B
42	Compton	1200.0 µg/L	No	8	B
43	Laguna Beach	1200.0 µg/L	No	2	B
44	Lake Forest	1200.0 µg/L	No	38	B-
45	San Clemente	1200.0 µg/L	No	3	A-
46	Beverly Hills	1200.0 µg/L	No	18	B
47	Calexico	1200.0 µg/L	No	7	B-
48	Ramona	1200.0 µg/L	No	36	C
49	Phelan	1200.0 µg/L	No	0	B+
50	Vernon	1200.0 µg/L	No	3	A
51	Port Hueneme	1200.0 µg/L	No	0	B+
52	Lomita	1200.0 µg/L	No	1	A-
53	Santa Fe Springs	1200.0 µg/L	No	1	B+
54	Rosemead	1182.8 µg/L	No	17	C-
55	Escondido	1140.0 µg/L	No	10	B
56	Irvine	1100.0 µg/L	No	84	F
57	La Mesa	1100.0 µg/L	No	0	A+
58	Oxnard	1100.0 µg/L	No	49	F
59	Chula Vista	1100.0 µg/L	No	1	B+
60	Pomona	1100.0 µg/L	No	6	C+
61	Corona	1100.0 µg/L	No	81	D
62	Bakersfield	1100.0 µg/L	No	690	F
63	Davis	1100.0 µg/L	No	47	B+
64	San Marcos	1100.0 µg/L	No	27	D
65	Walnut	1100.0 µg/L	No	1	A-
66	Inglewood	1100.0 µg/L	No	3	A-
67	Lynwood	1100.0 µg/L	No	0	B+
68	Woodland	1100.0 µg/L	No	52	F
69	Brea	1100.0 µg/L	No	0	A
70	Cerritos	1100.0 µg/L	No	0	B
71	Valley Center	1100.0 µg/L	No	15	F
72	Lakeside	1100.0 µg/L	No	0	A-
73	Manhattan Beach	1100.0 µg/L	No	1	A-
74	Shafter	1100.0 µg/L	No	25	A-
75	El Segundo	1100.0 µg/L	No	0	A-
76	Tustin	1090.0 µg/L	No	8	B
77	Santa Ana	1070.0 µg/L	No	8	C
78	Garden Grove	1070.0 µg/L	No	2	B
79	Fullerton	1070.0 µg/L	No	8	B
80	Orange	1070.0 µg/L	No	3	B
81	Westminster	1070.0 µg/L	No	2	A-
82	Placentia	1070.0 µg/L	No	0	B+
83	Buena Park	1070.0 µg/L	No	1	B+
84	Newport Beach	1070.0 µg/L	No	4	B+
85	Fountain Valley	1070.0 µg/L	No	0	A
86	Los Angeles	1040.0 µg/L	No	94	F
87	Seal Beach	1040.0 µg/L	No	0	A-
88	Sacramento	1000.0 µg/L	No	425	F
89	Perris	1000.0 µg/L	No	0	A
90	Rowland Heights	1000.0 µg/L	No	0	B+
91	Glendora	1000.0 µg/L	No	0	A-
92	Huntington Park	1000.0 µg/L	No	3	B+
93	Lathrop	1000.0 µg/L	No	44	B
94	Trabuco Canyon	1000.0 µg/L	No	2	A-
95	Scotts Valley	1000.0 µg/L	No	11	B-
96	Covina	990.0 µg/L	No	10	B
97	Spring Valley	990.0 µg/L	No	4	B
98	Hemet	990.0 µg/L	No	31	B-
99	Vista	980.0 µg/L	No	0	A-
100	Lodi	980.0 µg/L	No	16	C+
101	Colton	980.0 µg/L	No	5	B-
102	Long Beach	970.0 µg/L	No	2	C
103	Rancho Santa Fe	970.0 µg/L	No	3	A-
104	Pasadena	960.0 µg/L	No	92	F
105	Laguna Hills	960.0 µg/L	No	1	B+
106	Burbank	960.0 µg/L	No	1	A-
107	Poway	960.0 µg/L	No	0	A-
108	La Palma	960.0 µg/L	No	0	A-
109	Sierra Madre	960.0 µg/L	No	5	A
110	Encinitas	950.0 µg/L	No	55	F
111	Carlsbad	950.0 µg/L	No	0	A+
112	Ripon	950.0 µg/L	No	10	A-
113	San Diego	940.0 µg/L	No	43	F
114	Norwalk	940.0 µg/L	No	1	A-
115	Soledad	930.0 µg/L	No	28	C+
116	Whittier	900.0 µg/L	No	4	C+
117	Costa Mesa	899.0 µg/L	No	2	A-
118	Victorville	890.0 µg/L	No	1	B+
119	Paramount	890.0 µg/L	No	0	A-
120	Carpinteria	890.0 µg/L	No	5	A
121	Nuevo	890.0 µg/L	No	6	B+
122	La Crescenta	880.0 µg/L	No	3	B+
123	Santee	860.0 µg/L	No	14	B
124	Imperial Beach	840.3 µg/L	No	1	A
125	Lake Elsinore	840.0 µg/L	No	8	A
126	Santa Monica	840.0 µg/L	No	0	B
127	Discovery Bay	840.0 µg/L	No	3	A+
128	Riverbank	830.0 µg/L	No	75	D
129	Bellflower	820.0 µg/L	No	0	B+
130	Greenfield	820.0 µg/L	No	17	B
131	South Gate	800.0 µg/L	No	2	B
132	Stockton	790.0 µg/L	No	261	F
133	Pico Rivera	780.0 µg/L	No	4	B
134	Paso Robles	770.0 µg/L	No	42	F
135	Oak View	770.0 µg/L	No	12	B+
136	Ridgecrest	760.0 µg/L	No	26	A-
137	Firebaugh	760.0 µg/L	No	89	D
138	Quartz Hill	750.0 µg/L	No	1	A-
139	San Bernardin0	740.0 µg/L	No	0	A-
140	Norco	740.0 µg/L	No	39	F
141	Chowchilla	740.0 µg/L	No	25	A-
142	Marina	730.0 µg/L	No	4	A+
143	Bell Gardens	720.0 µg/L	No	0	B
144	Wasco	710.0 µg/L	No	26	B+
145	Fort Irwin	710.0 µg/L	No	60	B+
146	Adelanto	700.0 µg/L	No	13	C
147	Grand Terrace	690.0 µg/L	No	1	B
148	Jurupa Valley	680.0 µg/L	No	62	B
149	Lakewood	670.0 µg/L	No	1	A-
150	El Monte	660.0 µg/L	No	79	F
151	Merced	660.0 µg/L	No	9	C+
152	Turlock	660.0 µg/L	No	16	B-
153	Hamilton City	652.0 µg/L	No	0	A+
154	Montebello	650.0 µg/L	No	5	B
155	Cudahy	640.0 µg/L	No	3	B+
156	Highland	630.0 µg/L	No	3	B+
157	Tulare	630.0 µg/L	No	61	C-
158	Petaluma	630.0 µg/L	No	2	B
159	Apple Valley	630.0 µg/L	No	57	D
160	Indio	620.0 µg/L	No	12	F
161	Westlake Village	620.0 µg/L	No	8	F
162	Thousand Oaks	610.0 µg/L	No	1	A
163	Signal Hill	610.0 µg/L	No	6	B
164	Santa Maria	600.0 µg/L	No	36	F
165	Desert Hot Springs	600.0 µg/L	No	4	A
166	Vacaville	600.0 µg/L	No	26	F
167	Calabasas	590.0 µg/L	No	14	A-
168	Camp Pendleton	590.0 µg/L	No	13	B
169	Arvin	590.0 µg/L	No	81	C+
170	La Verne	580.0 µg/L	No	6	B+
171	Reedley	580.0 µg/L	No	12	B-
172	Baldwin Park	570.0 µg/L	No	1	A
173	Monterey Park	570.0 µg/L	No	1	B
174	Altadena	570.0 µg/L	No	2	B+
175	San Fernando	570.0 µg/L	No	1	A+
176	Ontario	560.0 µg/L	No	1	B+
177	Exeter	560.0 µg/L	No	41	B
178	Gilroy	550.0 µg/L	No	28	C+
179	Soquel	550.0 µg/L	No	1	A
180	Taft	550.0 µg/L	No	0	A-
181	Arroyo Grande	545.0 µg/L	No	93	F
182	Lompoc	540.0 µg/L	No	18	C
183	Arcadia	540.0 µg/L	No	2	B
184	Azusa	530.0 µg/L	No	2	B+
185	Watsonville	530.0 µg/L	No	74	F
186	Salinas	530.0 µg/L	No	639	F
187	Delano	530.0 µg/L	No	67	B
188	Riverside	520.0 µg/L	No	13	C
189	San Bruno	520.0 µg/L	No	0	A+
190	Nipomo	520.0 µg/L	No	1	A
191	Fresno	510.0 µg/L	No	523	F
192	Palmdale	510.0 µg/L	No	15	C+
193	Madera	510.0 µg/L	No	564	D
194	Atascadero	510.0 µg/L	No	1	B
195	Rialto	500.0 µg/L	No	6	B+
196	Sunnyvale	500.0 µg/L	No	3	A
197	Redding	500.0 µg/L	No	49	F
198	Atwater	500.0 µg/L	No	3	B+
199	Arcata	500.0 µg/L	No	3	A
200	Lamont	490.0 µg/L	No	40	B+
201	Livingston	490.0 µg/L	No	29	C-
202	Cupertino	480.0 µg/L	No	3	A+
203	Milpitas	470.0 µg/L	No	2	A-
204	Grover Beach	470.0 µg/L	No	34	F
205	Citrus Heights	460.0 µg/L	No	2	A
206	Chino	450.0 µg/L	No	9	B
207	Chino Hills	450.0 µg/L	No	2	A
208	Palm Springs	450.0 µg/L	No	16	B
209	San Luis Obispo	450.0 µg/L	No	27	F
210	Santa Clara	440.0 µg/L	No	5	B
211	Mountain View	430.0 µg/L	No	3	A
212	Pala	430.0 µg/L	No	30	C-
213	Gonzales	428.4 µg/L	No	53	F
214	Olivehurst	420.0 µg/L	No	2	A
215	Rosamond	420.0 µg/L	No	205	F
216	Simi Valley	410.0 µg/L	No	3	A
217	Porterville	410.0 µg/L	No	74	F
218	Elk Grove	410.0 µg/L	No	28	C
219	Oakdale	410.0 µg/L	No	34	C-
220	Kingsburg	410.0 µg/L	No	17	B
221	Fremont	400.0 µg/L	No	3	B-
222	Roseville	400.0 µg/L	No	11	B
223	Montclair	400.0 µg/L	No	0	B+
224	Twentynine Palms	400.0 µg/L	No	70	B+
225	Pacific Grove	397.7 µg/L	No	15	B-
226	Hesperia	390.0 µg/L	No	2	B
227	California City	390.0 µg/L	No	22	A-
228	San Bernardino	380.0 µg/L	No	192	F
229	Loma Linda	380.0 µg/L	No	3	A
230	Edwards Afb	380.0 µg/L	No	8	A-
231	Dinuba	380.0 µg/L	No	24	A-
232	Clovis	370.0 µg/L	No	221	F
233	Truckee	370.0 µg/L	No	7	A-
234	Coachella	370.0 µg/L	No	11	C-
235	Eureka	370.0 µg/L	No	3	A-
236	Sanger	370.0 µg/L	No	16	C
237	Fontana	360.0 µg/L	No	0	A-
238	Redlands	360.0 µg/L	No	2	B
239	Lemoore	360.0 µg/L	No	112	D
240	Livermore	360.0 µg/L	No	53	B
241	Yucca Valley	360.0 µg/L	No	7	A-
242	Kerman	360.0 µg/L	No	13	B
243	Parlier	360.0 µg/L	No	14	A-
244	Rancho Cucamonga	350.0 µg/L	No	0	B+
245	Healdsburg	350.0 µg/L	No	12	B+
246	Mckinleyville	348.0 µg/L	No	2	A-
247	Yucaipa	340.0 µg/L	No	9	C+
248	Avenal	340.0 µg/L	No	35	B
249	South Lake Tahoe	330.0 µg/L	No	15	C
250	Upland	330.0 µg/L	No	4	B+
251	Monrovia	330.0 µg/L	No	0	B+
252	Oakland	320.0 µg/L	No	13	B
253	Pittsburg	320.0 µg/L	No	0	A
254	Ukiah	320.0 µg/L	No	14	C+
255	South Pasadena	320.0 µg/L	No	5	A
256	San Jacinto	320.0 µg/L	No	9	B
257	Temescal Valley	320.0 µg/L	No	2	A
258	Coalinga	320.0 µg/L	No	267	D
259	Morro Bay	320.0 µg/L	No	12	A-
260	Clearlake	310.0 µg/L	No	5	B+
261	Oakley	300.0 µg/L	No	60	D
262	Windsor	300.0 µg/L	No	2	A+
263	Montara	296.0 µg/L	No	3	A-
264	Los Osos	286.7 µg/L	No	0	B+
265	Carmichael	280.0 µg/L	No	1	B+
266	Red Bluff	280.0 µg/L	No	23	F
267	Fortuna	279.0 µg/L	No	7	B-
268	Bermuda Dunes	278.0 µg/L	No	0	A+
269	Santa Cruz	260.0 µg/L	No	38	F
270	Beaumont	260.0 µg/L	No	2	A-
271	Rohnert Park	260.0 µg/L	No	21	F
272	Stanford	260.0 µg/L	No	3	A+
273	Boulder Creek	250.0 µg/L	No	119	F
274	Rio Linda	250.0 µg/L	No	2	A-
275	29 Palms	250.0 µg/L	No	3	B
276	Santa Rosa	240.0 µg/L	No	177	F
277	Fairfield	240.0 µg/L	No	7	B-
278	Daly City	240.0 µg/L	No	4	A
279	Palo Alto	240.0 µg/L	No	8	A-
280	Novato	240.0 µg/L	No	3	B+
281	Fair Oaks	240.0 µg/L	No	0	B+
282	El Verano	240.0 µg/L	No	0	B+
283	Millbrae	240.0 µg/L	No	1	A-
284	Farmersville	240.0 µg/L	No	20	B+
285	Corte Madera	210.0 µg/L	No	0	A-
286	Lincoln	210.0 µg/L	No	6	A-
287	Belmont	210.0 µg/L	No	3	A+
288	Banning	200.0 µg/L	No	15	B-
289	American Canyon	200.0 µg/L	No	15	A-
290	Sonoma	200.0 µg/L	No	5	B-
291	Concord	190.0 µg/L	No	19	B-
292	Antioch	190.0 µg/L	No	3	A
293	Martinez	180.0 µg/L	No	0	A
294	Galt	180.0 µg/L	No	27	B+
295	Hillsborough	180.0 µg/L	No	7	A
296	Burlingame	170.0 µg/L	No	14	A-
297	Vallejo	170.0 µg/L	No	6	A
298	Napa	170.0 µg/L	No	53	F
299	Benicia	170.0 µg/L	No	1	A-
300	Chico	150.0 µg/L	No	306	F
301	Mammoth Lakes	150.0 µg/L	No	24	B
302	Cottonwood	147.0 µg/L	No	7	B
303	Anderson	144.0 µg/L	No	14	C-
304	San Andreas	140.0 µg/L	No	17	B-
305	Mcfarland	140.0 µg/L	No	42	C+
306	West Sacramento	130.0 µg/L	No	1	B+
307	Cutten	130.0 µg/L	No	5	A+
308	Brooks	120.0 µg/L	No	2	B+
309	Susanville	119.0 µg/L	No	34	A-
310	Pacifica	110.0 µg/L	No	2	A
311	Corcoran	110.0 µg/L	No	3	A
312	Kirkwood	110.0 µg/L	No	0	A
313	Menlo Park	97.0 µg/L	No	2	A-
314	Hanford	92.0 µg/L	No	197	D+
315	Sonora	79.0 µg/L	No	25	D+
316	Half Moon Bay	72.0 µg/L	No	6	A
317	Yuba City	70.0 µg/L	No	24	A-
318	Granite Bay	64.0 µg/L	No	43	B-
319	Shasta Lake 4510007	63.6 µg/L	No	1	A+
320	Orangevale	59.0 µg/L	No	0	A
321	Placerville	55.0 µg/L	No	6	A-
322	Hayward	53.0 µg/L	No	0	A-
323	East Palo Alto	50.5 µg/L	No	8	A
324	Auburn	49.0 µg/L	No	8	A
325	Foster City	48.0 µg/L	No	2	A+
326	Oroville	48.0 µg/L	No	7	C-
327	Crescent City	48.0 µg/L	No	14	C
328	Redwood City	47.0 µg/L	No	10	B+
329	Paradise	46.0 µg/L	No	2	A
330	Folsom	45.0 µg/L	No	1	A-
331	Grass Valley	45.0 µg/L	No	8	A
332	Brownsville	34.9 µg/L	No	0	A-
333	Mendota	31.0 µg/L	No	3	A

FAQ

Frequently asked questions about strontium in California

Is strontium in California tap water harmful?

Strontium at low levels is not considered harmful, but the EPA set a health reference level (HRL) of 1,500 µg/L based on potential bone effects. 19 cities in California exceed this HRL. There is currently no federal MCL for strontium. Children may be more susceptible because strontium can substitute for calcium in developing bones.

How can I remove strontium from my drinking water?

Reverse osmosis and ion exchange (water softener) systems are effective at removing strontium from drinking water. Standard carbon filters are NOT effective. If your water comes from a well in an area with limestone or dolomite geology, consider testing for strontium.

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