CA / San Francisco
CA · Tap water records
San Francisco tap water, in plain English
Here is what the EPA's own data shows about tap water in San Francisco. According to EPA SDWIS data retrieved June 2026, San Francisco is served by 13 active community water systems, together reported to serve about 7,597 people.
As of June 2026, EPA records show 197 violations across the community water system(s) serving San Francisco, going back to the earliest EPA record. 93 of these are classified by the EPA as health-based (a contaminant recorded above the limit the EPA tracks); the rest are monitoring or reporting violations. Each is listed by system below, with its status.
What the EPA has on record, by system
Presidio Of San Francisco
3,500 served · surface water · PWSID CA3810700 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Joshua Valley Utility Company
1,500 served · groundwater · PWSID AZ0408017 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Hillcrest Estates Mhp
850 served · groundwater · PWSID WI6180285 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Villa Diann Mhp
420 served · groundwater · PWSID WI6180290 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Mountain Vale Village Mhp
388 served · groundwater · PWSID NH0513100 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Mile High Mobile Home Park
209 served · surface water · PWSID CO0101511 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Ridgewood Mobile Home Park
196 served · surface water · PWSID CO0130676 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
By Way Mobile Home Park
150 served · groundwater · PWSID OH2500212 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Longview Mobile Home Park
147 served · surface water · PWSID CO0116484 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
The Hideout At Glenwood Springs
94 served · groundwater · PWSID CO0223343 As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
Six Acres Water Company
66 served · surface water · PWSID CA4900608 - Health-based Groundwater Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 9 times between August 2021 and July 2024. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
- Health-based Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in July 2020. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
- Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 5 times between January 2015 and January 2021. EPA records do not show all of these as returned to compliance.
- Monitoring Alkalinity, Bicarbonate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Calcium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Alkalinity, Carbonate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Hardness, Total (as CaC03): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Hydroxide as Calcium Carbonate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Magnesium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring pH: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Sodium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Turbidity: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Arsenic: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Nitrite: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Trichlorofluoromethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring METHYL TERT-BUTYL ETHER: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,2,4-Trichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring cis-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,3-DICHLOROPROPENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring TRICHLOROTRIFLUOROETHANE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Xylenes, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring DICHLOROMETHANE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring o-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring p-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Vinyl chloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1-Dichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring trans-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,2-Dichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1,1-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Carbon tetrachloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,2-Dichloropropane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Trichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1,2-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Tetrachloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1,2,2-Tetrachloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring CHLOROBENZENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Benzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Toluene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Ethylbenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Styrene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Atrazine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Carbofuran: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Dalapon: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Dinoseb: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Diquat: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Endothall: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring OXAMYL: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Pentachlorophenol: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Picloram: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Simazine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
- Monitoring contaminant code null: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2014. All have since returned to compliance, per EPA records.
Sonoma County Mutual Water Company
40 served · surface water · PWSID CA4900640 - Health-based Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 83 times between December 2011 and July 2020. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Sunrise Mobilehome Park
37 served · groundwater · PWSID CA4500104 - Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2014. All have since returned to compliance, per EPA records.
What this means
A health-based violation means a contaminant was recorded above the limit the EPA tracks for it. A monitoring or reporting violation means a required test or report was late or missed — not that a contaminant was measured above a limit. “Returned to compliance” means the EPA recorded the issue as resolved.
This page summarizes the EPA's own records and does not assess whether your water is safe to drink. For the most current details, you can verify every record directly with the EPA, and contact your water system with questions.
Source: U.S. EPA Envirofacts SDWIS, retrieved June 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.