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Tap water quality report

Montello Waterworks

EPA monitoring tested this supplier for 73 contaminants and detected 15. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

73
contaminants tested
15
detected
1,329
people served
18
health-based violations
Wisconsin rankingsLead in WisconsinPFAS in Wisconsin
Water source
Ground water
Ownership
Local government
Counties served
Marquette

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

18
health-based violations
31
violations on file
3
still open
ViolationTypeStatusPeriod
TT Health-based Resolved 2025-04-29
TT Health-based Resolved 2025-04-29
TT Health-based Resolved 2025-04-29
TT Health-based Resolved 2024-10-17
MCL Health-based Resolved 2009-06-01 → 2009-06-30
MCL Health-based Resolved 2009-06-01 → 2009-06-30
MCL Health-based Resolved 2009-06-01 → 2009-06-30
MCL Health-based Resolved 2009-06-01 → 2009-06-30
MCL Health-based Resolved 2009-06-01 → 2009-06-30
TT Health-based Resolved 1994-07-01

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Fluoride
1070 µg/L 27%
of the EPA limit 4000 µg/L
worst single sample: 1100 µg/L
41/82 SYR4 2012–2017
Nitrate
3855 µg/L 39%
of the EPA limit 10000 µg/L
worst single sample: 3900 µg/L
24/24 SYR4 2012–2019
Copper
182.5 µg/L 14%
of the EPA limit 1300 µg/L
worst single sample: 230 µg/L
20/20 SYR4 2014–2017
Lead
5.51 µg/L 37%
of the EPA limit 15 µg/L
worst single sample: 9.5 µg/L
20/20 SYR4 2014–2017
Lead
0.0050 mg/L 33%
of the EPA limit 0.0150 mg/L
 19/19 LCR 2023
TTHM
2.24 µg/L 2.8%
of the EPA limit 80 µg/L
worst single sample: 2.5 µg/L
9/9 SYR4 2013–2019
Total Haloacetic Acids (HAA5)
0.8080 µg/L 1.3%
of the EPA limit 60 µg/L
worst single sample: 0.8200 µg/L
7/7 SYR4 2013–2019
Dibromoacetic Acid
0.7800 µg/L
No EPA limit set
 6/7 SYR4 2013–2019
Barium
19.85 µg/L 1%
of the EPA limit 2000 µg/L
worst single sample: 20 µg/L
4/4 SYR4 2014–2017
Chromium
1.585 µg/L 1.6%
of the EPA limit 100 µg/L
worst single sample: 1.6 µg/L
4/4 SYR4 2014–2017
Nitrate-Nitrite
3500 µg/L 35%
of the EPA limit 10000 µg/L
 4/4 SYR4 2014–2017
Bromoform
0.9270 µg/L
No EPA limit set
worst single sample: 0.9600 µg/L
3/9 SYR4 2013–2019
Dibromochloromethane
0.9640 µg/L
No EPA limit set
worst single sample: 0.9900 µg/L
3/9 SYR4 2013–2019
Combined Radium (-226 And -228)
1.495 pCi/L 30%
of the EPA limit 5 pCi/L
worst single sample: 1.5 pCi/L
2/2 SYR4 2014
Dichloroacetic Acid
0.2000 µg/L
No EPA limit set
 1/7 SYR4 2013–2019
58 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane2,4,5-TP2,4-DAntimony, TotalArsenicAtrazineBhc-GammaBenzeneBeryllium, TotalBromodichloromethaneChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneChloroformDichloromethaneDalaponDinosebDiquatEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonobromoacetic AcidMonochloroacetic AcidNitriteOxamylPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroacetic AcidTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Frequently asked questions about Montello Waterworks

Is Montello Waterworks tap water safe to drink?

EPA monitoring detected 15 contaminants in Montello Waterworks's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Montello Waterworks's water?

EPA monitoring detected Fluoride, Nitrate, Copper, Lead, Lead, and others. The full list with the level and data source for each is above.

How many people does Montello Waterworks serve?

Montello Waterworks reports serving 1,329 people in Wisconsin, per its EPA record.

Has Montello Waterworks had any water quality violations?

The EPA has 31 violations on file for Montello Waterworks, of which 18 are health-based (a contaminant limit or required treatment was breached) and 3 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.