Chlorate in Utah Drinking Water
Ranked by max chlorate detected (µg/L) · UCMR 3 data (2013–2015) · Data from EPA SDWIS & UCMR
Chlorate in Utah: what the data shows
Utah has 29 cities with chlorate data from the EPA's UCMR 3 program (2013–2015). Chlorate exceeded the 210 µg/L EPA lifetime health advisory in 9 of those cities. The state average max detected level is 186.2 µg/L. Chlorate is a disinfection byproduct that forms when chlorine dioxide or hypochlorite solutions are used to disinfect drinking water. It is most common in systems that use chlorine dioxide for taste-and-odor control or that store hypochlorite for extended periods. There is no federal MCL — the EPA lifetime health advisory is 210 µg/L. Chlorate can interfere with thyroid function by blocking iodide uptake, an effect of particular concern for pregnant women, infants, and people with thyroid conditions. Reverse osmosis and ion exchange (anion-specific) are effective at removing chlorate; standard activated carbon filters provide only modest reduction.
Cities exceeding 210 µg/L EPA lifetime HA (no MCL)
Chlorate data across Utah
Each dot is a city with UCMR 3 chlorate testing data. Cities where chlorate exceeds the 210 µg/L EPA lifetime health advisory are highlighted. Size reflects population served.
Top 10 cities by chlorate level in Utah
Highest Chlorate levels (µg/L)
All Utah cities ranked by chlorate level
| # | City | Level | Level | Over HA? | Violations | Grade |
|---|---|---|---|---|---|---|
| 1 | West Haven | 1100.0 µg/L | Over HA | 2 | B+ | |
| 2 | Eagle Mountain | 322.7 µg/L | Over HA | 25 | D | |
| 3 | Salt Lake City | 310.0 µg/L | Over HA | 26 | F | |
| 4 | Hurricane | 270.0 µg/L | Over HA | 8 | C+ | |
| 5 | Brigham City | 250.0 µg/L | Over HA | 14 | C- | |
| 6 | West Jordan | 225.2 µg/L | Over HA | 7 | C+ | |
| 7 | Ogden | 223.0 µg/L | Over HA | 5 | F | |
| 8 | Farr West | 215.3 µg/L | Over HA | 7 | B- | |
| 9 | Riverton | 211.6 µg/L | Over HA | 1 | B+ | |
| 10 | Draper | 208.6 µg/L | No | 18 | F | |
| 11 | Herriman | 200.9 µg/L | No | 13 | D+ | |
| 12 | Syracuse | 156.3 µg/L | No | 3 | B- | |
| 13 | Kearns | 155.3 µg/L | No | 6 | B | |
| 14 | Kaysville | 148.2 µg/L | No | 7 | C+ | |
| 15 | Plain City | 142.0 µg/L | No | 2 | B | |
| 16 | Coalville | 132.9 µg/L | No | 21 | F | |
| 17 | Magna | 116.2 µg/L | No | 1 | B+ | |
| 18 | Price | 110.0 µg/L | No | 5 | D | |
| 19 | Bluffdale | 108.3 µg/L | No | 7 | C | |
| 20 | South Jordan | 105.5 µg/L | No | 4 | C+ | |
| 21 | Layton | 105.4 µg/L | No | 1 | A- | |
| 22 | Clinton | 104.8 µg/L | No | 9 | C+ | |
| 23 | Elwood | 89.0 µg/L | No | 8 | B- | |
| 24 | Tooele | 80.0 µg/L | No | 5 | F | |
| 25 | Roy | 76.7 µg/L | No | 1 | B- | |
| 26 | North Salt Lake | 74.0 µg/L | No | 4 | C- | |
| 27 | St George City | 73.0 µg/L | No | 4 | B+ | |
| 28 | Wellsville | 43.0 µg/L | No | 16 | D+ | |
| 29 | Bountiful | 42.3 µg/L | No | 9 | D |
Frequently asked questions about chlorate in Utah
Is chlorate in Utah tap water dangerous?
Chlorate has no federal MCL. The EPA lifetime health advisory is 210 µg/L. 9 cities in Utah exceed this level. Chlorate can interfere with thyroid iodide uptake, which is a particular concern for infants, pregnant women, and people with hypothyroidism.
Where does chlorate in Utah water come from?
Chlorate is a byproduct of chlorine-based disinfectants — particularly chlorine dioxide and hypochlorite (bleach) solutions. Levels tend to be higher in systems that use chlorine dioxide for taste-and-odor treatment or store sodium hypochlorite at high concentrations or for long periods. Levels vary seasonally with disinfectant use.
How can I reduce chlorate exposure?
Reverse osmosis is the most effective home treatment for chlorate, typically removing 80–95%. Anion exchange systems also work but require regeneration. Standard activated carbon filters provide only limited chlorate reduction. Boiling does NOT remove chlorate.