MARIPOSA, CA

Total Incidents:
184
Last Incident:
October 01, 2017

Note: Just because the latest incident is in 2017 or 2018 doesn't mean your water is free of contaminants! There is a considerable lag between when data is collected and when it is published by the EPA.

Contaminants

All Incidents

Water System Type Measure Violation Effects Begin Date
MCCLURE BOAT CLUB, INC. TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2017-10-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2016-07-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2016-07-01
MUSD - CATHEYS VALLEY ELEMENTARY SCHOOL Nitrate MCL, Single Sample Maximum Contaminant Level Violation Infants below the age of six months who drink water containing nitrate in excess of the MCL could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue-baby syndrome. 2016-06-01
MUSD - CATHEYS VALLEY ELEMENTARY SCHOOL Nitrate MCL, Single Sample Maximum Contaminant Level Violation Infants below the age of six months who drink water containing nitrite in excess of the MCL could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue-baby syndrome. 2016-06-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2016-04-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2016-04-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2016-01-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2016-01-01
MARIPOSA PINES MUTUAL Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2015-10-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-10-01
MARIPOSA PINES MUTUAL Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2015-10-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-10-01
USFS - DRY GULCH/DIRT FLAT CAMPGROUND Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2015-08-01
USFS - DRY GULCH/DIRT FLAT CAMPGROUND Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2015-08-01
YOSEMITE NPS-VOGELSANG Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2015-07-01
YOSEMITE NPS-VOGELSANG Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2015-07-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-07-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-07-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-04-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-04-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-01-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2015-01-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-10-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-10-01
FISHCAMP MUTUAL WATER COMPANY Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-08-01
FISHCAMP MUTUAL WATER COMPANY Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-08-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-07-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-07-01
YOSEMITE NPS-VOGELSANG Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-07-01
THE COTTAGES AT TENAYA LODGE Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-07-01
YOSEMITE NPS-VOGELSANG Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-07-01
THE COTTAGES AT TENAYA LODGE Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-07-01
USFS - DRY GULCH/DIRT FLAT CAMPGROUND Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-06-01
MCPR-CATHEY S VALLEY PARK Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-06-01
USFS - DRY GULCH/DIRT FLAT CAMPGROUND Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-06-01
MCPR-CATHEY S VALLEY PARK Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-06-01
CEDAR LODGE RESORT Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-04-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-04-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-04-01
CEDAR LODGE RESORT Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2014-04-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-01-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2014-01-01
BOOTJACK STOMPERS HALL Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-11-01
BOOTJACK STOMPERS HALL Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-11-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2013-10-01
MARIPOSA COUNTY PUBLIC WORKS DEPARTMENT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2013-10-01
TAVIS CORPORATION Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-08-01
TAVIS CORPORATION Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-08-01
THE COTTAGES AT TENAYA LODGE Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-07-01
PONDEROSA BASIN MUTUAL WTR CO Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-07-01
PONDEROSA BASIN MUTUAL WTR CO Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-07-01
THE COTTAGES AT TENAYA LODGE Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-07-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2013-04-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2013-04-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2013-04-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2013-04-01
MARIPOSA PINES MUTUAL Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-01-01
MARIPOSA PINES MUTUAL Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2013-01-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2013-01-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2013-01-01
CEDAR LODGE RESORT Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2012-11-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-10-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-10-01
MCPR-CATHEY S VALLEY PARK Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2012-10-01
MCPR-CATHEY S VALLEY PARK Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2012-10-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-10-01
MARIPOSA PUBLIC UTILITY DIST Total Haloacetic Acids (HAA5) MCL, Average Maximum Contaminant Level Violation Increased risk of cancer 2012-10-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-10-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-07-01
MARIPOSA PUBLIC UTILITY DIST Total Haloacetic Acids (HAA5) MCL, Average Maximum Contaminant Level Violation Increased risk of cancer 2012-07-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-07-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-07-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-07-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-07-01
MARIPOSA PUBLIC UTILITY DIST Total Haloacetic Acids (HAA5) MCL, Average Maximum Contaminant Level Violation Increased risk of cancer 2012-07-01
MARIPOSA PINES MUTUAL Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2012-06-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-04-01
MARIPOSA PUBLIC UTILITY DIST Total Haloacetic Acids (HAA5) MCL, Average Maximum Contaminant Level Violation Increased risk of cancer 2012-04-01
MARIPOSA PUBLIC UTILITY DIST Total Haloacetic Acids (HAA5) MCL, Average Maximum Contaminant Level Violation Increased risk of cancer 2012-04-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-04-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-04-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-04-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-04-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-01-01
MARIPOSA PUBLIC UTILITY DIST Total Haloacetic Acids (HAA5) MCL, Average Maximum Contaminant Level Violation Increased risk of cancer 2012-01-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2012-01-01
MARIPOSA PUBLIC UTILITY DIST Total Haloacetic Acids (HAA5) MCL, Average Maximum Contaminant Level Violation Increased risk of cancer 2012-01-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-01-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-01-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2012-01-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2011-10-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2011-10-01
MID -HORSESHOE BEND REC AREA Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2011-07-01
MID-BAGBY RECREATION AREA Coliform (TCR) MCL, Acute (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2011-07-01
YOSEMITE WEST WATER SYSTEM Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2011-07-01
MPWD-COULTERVILLE CSA 1 Coliform (TCR) MCL, Monthly (TCR) Maximum Contaminant Level Violation Not a health threat in itself; it is used to indicate whether other potentially harmful bacteria may be present5 2011-07-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2011-07-01
CEDAR LODGE RESORT Arsenic MCL, Average Maximum Contaminant Level Violation Skin damage or problems with circulatory systems, and may have increased risk of getting cancer 2011-07-01
MARIPOSA PUBLIC UTILITY DIST TTHM MCL, Average Maximum Contaminant Level Violation Liver, kidney or central nervous system problems; increased risk of cancer 2011-04-01