Santa Rosa tap water, in plain English

As of July 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.

• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in October 2017. All have since returned to compliance, per EPA records.

• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in June 2022. All have since returned to compliance, per EPA records.

As of July 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.

As of July 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.

As of July 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.

As of July 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.

• 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 June 2014. All have since returned to compliance, per EPA records.

As of July 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.

• Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 8 times between October 2019 and 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.
• Health-based TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 10 times between October 2017 and April 2020. The EPA record lists a level of 0.089 MG/L; the limit (MCL) is 0.08 MG/L. EPA records do not show all of these as returned to compliance.
• Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in July 2021. EPA records do not show all of these as returned to compliance.
• Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in July 2021. EPA records do not show all of these as returned to compliance.
• Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in May 2019. All have since returned to compliance, per EPA records.

• Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 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 Arsenic: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in January 2021. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. EPA records do not show all of these as returned to compliance.

As of July 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.

• Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times between January 2015 and October 2015. The EPA record lists a level of 0.072 MG/L; the limit (MCL) is 0.06 MG/L. All have since returned to compliance, per EPA records.
• Health-based TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in July 2014. The EPA record lists a level of 0.082 MG/L; the limit (MCL) is 0.08 MG/L. All have since returned to compliance, per EPA records.

• Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2012. All have since returned to compliance, per EPA records.
• Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between January 2005 and January 2006. All have since returned to compliance, per EPA records.
• Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between January 2005 and January 2006. All have since returned to compliance, per EPA records.

• Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 2024. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. EPA records do not show all of these as returned to compliance.
• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 13 times between July 1993 and January 2024. All have since returned to compliance, per EPA records.
• Monitoring Antimony, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Aluminum: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Beryllium, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Barium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Cadmium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Chromium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Fluoride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Mercury: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Alkalinity, CaCO3 Stability: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Perchlorate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Selenium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Thallium, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2018. EPA records do not show all of these as returned to compliance.
• 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 2018. EPA records do not show all of these as returned to compliance.
• Monitoring contaminant code null: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2017. All have since returned to compliance, per EPA records.
• Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in August 2012. All have since returned to compliance, per EPA records.
• Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2006. All have since returned to compliance, per EPA records.
• Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2005. All have since returned to compliance, per EPA records.

• Health-based Groundwater Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in April 2019. 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 LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 2024. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. EPA records do not show all of these as returned to compliance.
• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between June 2021 and October 2022. EPA records do not show all of these as returned to compliance.

As of July 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.

• Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 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 Trichloroethylene: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 9 times between July 2014 and July 2016. The EPA record lists a level of 0.00854 MG/L; the limit (MCL) is 0.005 MG/L. All have since returned to compliance, per EPA records.
• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. EPA records do not show all of these as returned to compliance.
• 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 June 2009. All have since returned to compliance, per EPA records.
• Monitoring Nickel: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2007. All have since returned to compliance, per EPA records.

As of July 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.

• Monitoring contaminant code null: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in September 2025. EPA records do not show all of these as returned to compliance.
• Monitoring Arsenic: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in March 2001. All have since returned to compliance, per EPA records.
• Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in March 2001. 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 once in March 2001. 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 once in March 2001. All have since returned to compliance, per EPA records.
• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between July 1993 and March 1997. All have since returned to compliance, per EPA records.

• Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in September 2021. EPA records do not show all of these as returned to compliance.

As of July 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.

• Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 2024. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. EPA records do not show all of these as returned to compliance.
• Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2019. EPA records do not show all of these as returned to compliance.
• Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2019. EPA records do not show all of these as returned to compliance.
• 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 July 1993. All have since returned to compliance, per EPA records.

• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in June 2022. All have since returned to compliance, per EPA records.

• Health-based Arsenic: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between January 2021 and April 2021. The EPA record lists a level of 0.016 MG/L; the limit (MCL) is 0.01 MG/L. EPA records do not show all of these as returned to compliance.

• Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2019. EPA records do not show all of these as returned to compliance.
• Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2019. EPA records do not show all of these as returned to compliance.

• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 5 times between July 1993 and October 2020. 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 April 2009. All have since returned to compliance, per EPA records.
• Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2009. All have since returned to compliance, per EPA records.

• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2025. EPA records do not show all of these as returned to compliance.
• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between June 2009 and January 2024. EPA records do not show all of these as returned to compliance.
• Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between January 2005 and January 2018. EPA records do not show all of these as returned to compliance.
• Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between January 2005 and January 2018. EPA records do not show all of these as returned to compliance.

As of July 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.

• Health-based Arsenic: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times in October 2017. The EPA record lists a level of 0.017 MG/L; the limit (MCL) is 0.01 MG/L. All have since returned to compliance, per EPA records.
• Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 6 times between April 2020 and July 2020. EPA records do not show all of these as returned to compliance.

As of July 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.

As of July 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.

• Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 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 Long Term 2 Enhanced Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in February 2023. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
• Health-based Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between August 2007 and January 2021. The EPA record for these does not include a measured level. 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 2025. EPA records do not show all of these as returned to compliance.
• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. EPA records do not show all of these as returned to compliance.
• Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 6 times between October 2016 and January 2021. All have since returned to compliance, per EPA records.
• Monitoring Coliform (Pre-TCR): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in December 2019. All have since returned to compliance, per EPA records.
• Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in October 2019. All have since returned to compliance, per EPA records.
• Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2018. All have since returned to compliance, per EPA records.
• Monitoring Coliform (TCR): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in February 2016. 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 between January 2019 and April 2019. EPA records do not show all of these as returned to compliance.
• 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 June 2009. 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 once in July 1991. All have since returned to compliance, per EPA records.

As of July 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.

As of July 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.

As of July 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.

• Health-based Arsenic: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 36 times between October 2007 and October 2017. The EPA record lists a level of 0.0139 MG/L; the limit (MCL) is 0.01 MG/L. 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 once in October 2010. All have since returned to compliance, per EPA records.

• Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 2024. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
• Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. EPA records do not show all of these as returned to compliance.