Chico tap water, in plain English

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.

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.

• Health-based Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 4 times between February 2018 and February 2025. 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 Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 8 times between January 2022 and July 2022. The EPA record lists a level of 73 UG/L; the limit (MCL) is 60 UG/L. 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 2 times in September 2018. All have since returned to compliance, per EPA records.

• Health-based Nitrate: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 73 times between January 2003 and April 2024. The EPA record lists a level of 48.3 MG/L; the limit (MCL) is 45 MG/L. EPA records do not show all of these as returned to compliance.
• Health-based Combined Uranium: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 79 times between January 2016 and April 2024. The EPA record lists a level of 33.4 PCI/L; the limit (MCL) is 20 PCI/L. EPA records do not show all of these as returned to compliance.
• Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 24 times between December 2002 and April 2005. The EPA record for these does not include a measured level. 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 16 times between July 2003 and July 2016. 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 8 times between October 2005 and January 2012. 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 8 times between June 2005 and March 2007. 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 4 times in July 2003. All have since returned to compliance, per EPA records.

• Health-based Combined Uranium: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 16 times between April 2008 and October 2011. The EPA record lists a level of 23.1 PCI/L; the limit (MCL) is 20 PCI/L. All have since returned to compliance, per EPA records.
• Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 8 times between June 2004 and July 2004. The EPA record for these does not include a measured level. 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 12 times between December 1997 and August 2004. 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 12 times between January 2000 and January 2003. 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 between May 1996 and January 2003. 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 2000. All have since returned to compliance, per EPA records.

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.

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.

• Health-based Nitrate: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 10 times between November 2023 and August 2024. The EPA record lists a level of 13 MG/L; the limit (MCL) is 10 MG/L. 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 18 times between July 2003 and January 2006. The EPA record for these does not include a measured level. 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 3 times between August 2017 and December 2023. 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 2023. All have since returned to compliance, per EPA records.
• Monitoring 1,2,3-Trichloropropane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2020. EPA records do not show all of these as returned to compliance.

• Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between July 2009 and July 2025. 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 2 times in August 2023. 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 3 times in January 2022. 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 in January 2022. 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 once in January 2020. 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 2020. 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 2020. 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 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 January 2010. 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 4 times between January 1992 and June 1993. The EPA record lists a level of 0 ; the limit (MCL) is 0 . All have since returned to compliance, per EPA records.

• Health-based COPPER, FREE: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 4 times in January 2015. The EPA record for these does not include a measured level. 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 5 times in July 2022. 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 4 times in January 2002. All have since returned to compliance, per EPA records.

• Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in August 2000. 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: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between November 1996 and October 2025. EPA records do not show all of these as returned to compliance.
• Monitoring 1,2,3-Trichloropropane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between October 2021 and January 2022. EPA records do not show all of these as returned to compliance.
• Monitoring Coliform (TCR): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 4 times between August 2004 and July 2006. 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 3 times between January 1997 and January 1999. 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 2025. 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 once in July 1993. All have since returned to compliance, per EPA records.

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.

• 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 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 2025. 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 Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in April 2023. 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 July 2019. 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 March 2009. 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 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 once in October 2014. All have since returned to compliance, per EPA records.

• Health-based Interim Enhanced Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 4 times between March 2016 and May 2016. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
• Monitoring Surface Water Treatment Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 8 times between January 2016 and October 2016. 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 March 2009. 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 Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 4 times between May 2017 and September 2023. 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 2 times in January 2022. 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 2020. 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 3 times in January 2017. 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 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,2,4-Trichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring cis-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,3-DICHLOROPROPENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring TRICHLOROTRIFLUOROETHANE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Xylenes, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring DICHLOROMETHANE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring o-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring p-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Vinyl chloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,1-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,1-Dichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring trans-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,2-Dichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,1,1-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Carbon tetrachloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,2-Dichloropropane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Trichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring 1,1,2-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Tetrachloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• 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 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring CHLOROBENZENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Benzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Toluene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Ethylbenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.
• Monitoring Styrene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2017. EPA records do not show all of these as returned to compliance.

• Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times in June 2015. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
• Monitoring Nitrate-Nitrite: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2013. 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 once in July 1993. 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 3 times in June 2010. All have since returned to compliance, per EPA records.
• Monitoring Combined Radium (-226 and -228): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2007. 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 4 times between July 1993 and January 2007. 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 3 times in January 2007. All have since returned to compliance, per EPA records.

• Health-based Nitrate: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 18 times between November 2019 and October 2021. The EPA record lists a level of 11.3 MG/L; the limit (MCL) is 10 MG/L. 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 Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 15 times between June 2022 and August 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.

• Health-based Combined Uranium: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 10 times between April 2018 and October 2020. The EPA record lists a level of 35.3 PCI/L; the limit (MCL) is 20 PCI/L. All have since returned to compliance, per EPA records.
• Health-based Nitrate: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 22 times between January 2001 and October 2019. The EPA record lists a level of 62 MG/L; the limit (MCL) is 45 MG/L. All have since returned to compliance, per EPA records.
• Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 5 times between August 1997 and February 2016. The EPA record for these does not include a measured level. 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 2 times in August 2024. 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 3 times between October 2003 and January 2013. 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 October 2005 and January 2012. 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 2 times between January 1998 and March 2007. 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 2003. 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 once in October 2025. EPA records do not show all of these as returned to compliance.
• 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 2025. 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 2020. 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 2020. 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 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 2014. 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 once in July 1993. All have since returned to compliance, per EPA records.