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Tap water quality report

Jefferson, IA

EPA monitoring detected 19 contaminants across the 1 water supplier serving Jefferson. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

1
water supplier
4,182
people served
19
contaminants found
Iowa rankings Lead in Iowa PFAS in Iowa

What was found in Jefferson's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Nitrate
2200 µg/L 22%
of the EPA limit 10000 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Copper
1260 µg/L 97%
of the EPA limit 1300 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Fluoride
865.6499999999999 µg/L 22%
of the EPA limit 4000 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Barium
191 µg/L 9.6%
of the EPA limit 2000 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2013
1/1 SYR4
TTHM
88.85 µg/L 111%
of the EPA limit, at the 95th percentile of samples — 80 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Chloroform
61.75 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Total Haloacetic Acids (HAA5)
56.52999999999999 µg/L 94%
of the EPA limit 60 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Trichloroacetic Acid
29.73499999999999 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Bromodichloromethane
22.25 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Dichloroacetic Acid
18.604999999999997 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Monochloroacetic Acid
12.834999999999997 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Monobromoacetic Acid
8.8325 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Dibromochloromethane
5.65 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Lead
3.5850000000000004 µg/L 24%
of the EPA limit 15 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Arsenic
3.4699999999999998 µg/L 35%
of the EPA limit 10 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
cis-1,2-Dichloroethylene
2.145 µg/L 3.1%
of the EPA limit 70 µg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Dibromoacetic Acid
1.7649999999999997 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Bromoform
0.5000 µg/L
No EPA limit set
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2019
1/1 SYR4
Lead
0.00080 mg/L 5.3%
of the EPA limit 0.0150 mg/L
Main supplier: JEFFERSON WATER DEPARTMENT · 4,182 people · 2025
1/1 LCR
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 the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Jefferson

SupplierPopulation served
JEFFERSON WATER DEPARTMENT 4,182

Frequently asked questions about Jefferson tap water

Is Jefferson tap water safe to drink?

EPA testing detected 19 contaminants in the water serving Jefferson. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Jefferson?

1 public water supplier report drinking-water monitoring for Jefferson, Iowa to the EPA. Each is listed above with its population served.

What contaminants are in Jefferson's water?

The contaminants EPA monitoring detected in Jefferson include Nitrate, Copper, Fluoride, Barium, TTHM. The full list, with the level at the main supplier and the data source, is in the table above.

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.