Chico Water Quality
California
According to EPA SDWIS, Chico, California is served by 28 community water systems covering about 23,356 people. The same extract lists 314 health-based violation records, most recently coded 0200 in 2025. Counts are historical EPA registry rows, not a current compliance or drinkability score.
Drinking water in Chico, California is delivered through 28 EPA-regulated community water systems serving an estimated 23,356 people. Each system is tracked in the EPA Safe Drinking Water Information System (SDWIS) under the Safe Drinking Water Act, which requires testing for regulated contaminants, consumer notification of violations, and publication of an annual Consumer Confidence Report.
PlainEnviro's health-based SDWIS extract shows 314 violation records across the 28 active community systems shown here. Monitoring and reporting records are not present in the extract. The records carry 8 distinct EPA contaminant codes: Surface Water Treatment Rule, LEAD AND COPPER RULE REVISIONS, Nitrate, Combined Uranium, Total Haloacetic Acids (HAA5) and 3 others. 1 TRI-reporting industrial facility is also located within the city limits.
A past EPA health-based registry row does not describe water delivered today or current compliance status; utilities notify customers and remediate under state primacy oversight when required. For current water-quality status and treatment practices, review your local utility's most recent Consumer Confidence Report or contact the California drinking water program. All records above reflect federal EPA SDWIS data and are not independently verified against state databases.
Community Water Systems
| System Name | Pop. Served | Violations | Status |
|---|---|---|---|
| DEL ORO WATER CO.-PARADISE PINES | 10,940 | 0 | Clean |
| DEL ORO WATER CO-FERNDALE | 1,662 | 0 | Clean |
| DEL ORO WATER COMPANY - STRAWBERRY DIV. | 1,295 | 12 | Health |
| DEL ORO RIVER ISLAND SERV TERR #1 | 1,280 | 176 | Health |
| DEL ORO CALIFORNIA PINES DISTRICT | 944 | 24 | Health |
| DEL ORO WATER CO.-JOHNSON PARK | 904 | 0 | Clean |
| DEL ORO WATER CO.-LIME SADDLE MARINA | 895 | 0 | Clean |
| DEL ORO TRAVER DISTRICT | 657 | 10 | Health |
| DEL ORO WATER CO.-STIRLING BLUFFS | 521 | 18 | Health |
| GRIDLEY FARM LABOR HOUSING | 460 | 0 | Clean |
| SIERRA MOON MUTUAL WATER COMPANY | 450 | 1 | Health |
| BUTTE CREEK ESTATES MUTUAL WATER CO | 399 | 0 | Clean |
| BENBOW-DEL ORO W.C. | 347 | 4 | Health |
| DEL ORO WATER CO.-MAGALIA | 340 | 4 | Health |
| DEL ORO WC - COUNTRY ESTATES DIST | 297 | 1 | Health |
| GRAN MUTUAL WATER CO | 290 | 0 | Clean |
| DEL ORO WC - BLACK BUTTE DISTRICT | 277 | 0 | Clean |
| ALMOND GROVE MOBILE PARK | 253 | 1 | Health |
| DEL ORO WC - ARBUCKLE DISTRICT | 185 | 0 | Clean |
| DEL ORO WATER CO. - HAT CREEK DISTRICT | 185 | 4 | Health |
| KEEFER CREEK ESTATES | 160 | 0 | Clean |
| DEL ORO WC - LARKSPUR MEADOWS | 116 | 2 | Health |
| DEL ORO WATER COMPANY - BUZZTAIL DIST. | 106 | 0 | Clean |
| DEL ORO WATER CO - METROPOLITAN DISTRICT | 92 | 18 | Health |
| WEST COTTONWOOD APARTMENTS | 90 | 1 | Health |
| DEL ORO RIVER ISLAND SERV TERR #2 | 89 | 37 | Health |
| BLUE OAK TERRACE MUTUAL | 81 | 0 | Clean |
| HARTLEY MUTUAL WATER SYSTEM | 41 | 1 | Health |
Does this city have health-based water violations?
These health-based records can represent Maximum Contaminant Level (MCL), Treatment Technique (TT), or Maximum Residual Disinfectant Level (MRDL) categories. A historical record does not establish that water is currently unsafe.
| Water system | Contaminant | Begin Date |
|---|---|---|
| DEL ORO WATER COMPANY - STRAWBERRY DIV. | Surface Water Treatment Rule | 2025-02-01 |
| DEL ORO WATER COMPANY - STRAWBERRY DIV. | Surface Water Treatment Rule | 2025-02-01 |
| WEST COTTONWOOD APARTMENTS | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| SIERRA MOON MUTUAL WATER COMPANY | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| ALMOND GROVE MOBILE PARK | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| HARTLEY MUTUAL WATER SYSTEM | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-08-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-08-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-08-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-06-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-06-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-06-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2024-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2024-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2024-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2024-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2024-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2024-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2024-04-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-02-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2024-02-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2024-01-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2024-01-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2023-11-01 |
| DEL ORO TRAVER DISTRICT | Nitrate | 2023-11-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-10-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-10-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-10-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-08-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-08-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-08-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-08-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-08-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-07-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-06-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-06-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Nitrate | 2023-06-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-04-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-01-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2023-01-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2022-10-01 |
| DEL ORO RIVER ISLAND SERV TERR #1 | Combined Uranium | 2022-10-01 |
What are Chico's health-based records for?
Chico's health-based violation records carry 8 distinct EPA codes: some name a substance, others the drinking-water rule that was breached. Counts are records on file in the EPA SDWIS extract, not current test results.
| Contaminant | Records | Systems |
|---|---|---|
| Nitrate | 123 | 4 |
| Combined Uranium | 105 | 3 |
| Coliform (TCR) | 40 | 5 |
| Surface Water Treatment Rule | 26 | 3 |
| Total Haloacetic Acids (HAA5) | 8 | 1 |
| Lead and Copper Rule Revisions | 4 | 4 |
| Interim Enhanced Surface Water Treatment Rule | 4 | 1 |
| Copper, Free | 4 | 1 |
TRI Facilities in Chico
| Facility | Total Releases |
|---|---|
| A&a Concrete Supply Inc Chico Plant | 0 lbs |
Frequently Asked Questions
What does EPA SDWIS list for drinking water in Chico, California? ▼
How many water violations does Chico have in this EPA extract? ▼
What contaminants were found in Chico water? ▼
How many water systems serve Chico? ▼
Where does Chico get its drinking water? ▼
Are there pollution sources near Chico? ▼
How does Chico compare in California?
Of the 909 California places with at least one community water system on file, Chico ranks #9 by number of systems (28).
Either side of it: Santa Rosa (41), Madera (31), Bishop (24), Los Angeles (22)
About This Data
Figures here are the current EPA SDWIS extract joined to the 28 community water systems whose service area lists Chico, ranked against the 909 California places with at least one system on file. Data current as of 2026-08-25.
Water system data comes from the EPA's Safe Drinking Water Information System (SDWIS). PlainEnviro's violation fetch is restricted upstream to records EPA flags as health-based and then joined to active community water systems. Monitoring and reporting violations are not included.
A health-based violation row in this extract is a historical EPA registry entry. It does not describe water delivered today or current compliance status. Many records are later resolved, and public water systems notify customers when required. For current conditions, contact your local water utility or the state drinking water program.
TRI facility data comes from the EPA Toxic Release Inventory. Facilities shown are those that self-report to the TRI program. PlainEnviro presents this data without advocacy framing.
Read our methodology - how this data is sourced, computed, and verified.