The Power of Information

National Drinking Water Database

MTBE in Iowa

MTBE (methyl tert-butyl ether) is a fuel additive that had been used as an octane enhancer in unleaded gasoline; it contaminates groundwater due to spillage or leakage at gas stations, and has been banned or scheduled for phaseout in most states.

The Most Polluted Communities in Iowa

7 water utilities reported detecting MTBE in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by highest average MTBE level

RankSystem Population Served Positive test results of total reported tests Average Level
1Manning Water Supply
Manning, IA
1,4902 of 24.8 ppb
(3 to 6.6 ppb)
2Westside Water Supply
Westside, IA
3271 of 11.4 ppb
(1.4 ppb)
3Kiron Water Supply
Kiron, IA
2732 of 21.05 ppb
(0.5 to 1.6 ppb)
4Sioux Rapids Water Department
Sioux Rapi, IA
1,2981 of 11 ppb
(1 ppb)
5Kalona Water Dept
Kalona, IA
2,2932 of 21 ppb
(0.6 to 1.4 ppb)
6Minden Water Supply
Minden, IA
5642 of 40.92 ppb
(0 to 2.67 ppb)
7Mapleton Municipal Water Plant
Mapleton, IA
1,3221 of 10.7 ppb
(0.7 ppb)

Health Based Limits for MTBE

California Public Health GoalsDefined by the State of California Office of Environmental Health Hazard Assessment (OEHHA) as the level of contaminant that is allowed in drinking water. For acutely toxic substances, levels are set at which scientific evidence indicates that no known or anticipated adverse effects on health will occur, plus an adequate margin-of safety. PHGs for carcinogens or other substances which can cause chronic disease shall be based solely on health effects without regard to cost impacts and shall be set at levels which OEHHA has determined do not pose any significant risk to health.13 ppb

Violation Summary for MTBE in Iowa

There are no violations reported for this contaminant in Iowa