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Tap water quality report

Dekalb

EPA monitoring tested this supplier for 80 contaminants and detected 18. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

80
contaminants tested
18
detected
40,290
people served
66
health-based violations
Illinois rankingsLead in IllinoisPFAS in Illinois
Water source
Ground water
Ownership
Local government
Counties served
DeKalb

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.

66
health-based violations
85
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 1998-12-01 → 2002-05-14
MCL Health-based Resolved 1998-12-01 → 2002-05-14
MCL Health-based Resolved 1995-01-01 → 1998-11-30
MCL Health-based Resolved 1995-01-01 → 1998-11-30
MCL Health-based Resolved 1995-01-01 → 1998-11-30
MCL Health-based Resolved 1995-01-01 → 1998-11-30
MCL Health-based Resolved 1995-01-01 → 1998-11-30
MCL Health-based Resolved 1995-01-01 → 1998-11-30
MCL Health-based Resolved 1995-01-01 → 1998-11-30
MCL Health-based Resolved 1995-01-01 → 1998-11-30

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
Copper
634.25 µg/L 49%
of the EPA limit 1300 µg/L
worst single sample: 1000 µg/L
66/91 SYR4 2013–2019
Chloroform
21.44 µg/L
No EPA limit set
worst single sample: 24.5 µg/L
30/30 SYR4 2012–2019
TTHM
24.015 µg/L 30%
of the EPA limit 80 µg/L
worst single sample: 26.3 µg/L
30/30 SYR4 2012–2019
Total Haloacetic Acids (HAA5)
15.981 µg/L 27%
of the EPA limit 60 µg/L
worst single sample: 20.9 µg/L
30/30 SYR4 2012–2019
Trichloroacetic Acid
9.9855 µg/L
No EPA limit set
worst single sample: 11.9 µg/L
30/30 SYR4 2012–2019
Bromodichloromethane
3.5 µg/L
No EPA limit set
worst single sample: 4.91 µg/L
28/30 SYR4 2012–2019
Lead
12.2 µg/L 81%
of the EPA limit 15 µg/L
worst single sample: 14 µg/L
26/91 SYR4 2013–2019
Lead
0.0130 mg/L 87%
of the EPA limit 0.0150 mg/L
 25/25 LCR 2026
Combined Radium (-226 And -228)
5.585 pCi/L 112%
of the EPA limit, at the 95th percentile of samples — 5 pCi/L
worst single sample: 5.8 pCi/L
24/39 SYR4 2012–2019
Dichloroacetic Acid
6.0325 µg/L
No EPA limit set
worst single sample: 8.96 µg/L
24/30 SYR4 2012–2019
Barium
864.8 µg/L 43%
of the EPA limit 2000 µg/L
worst single sample: 946 µg/L
15/15 SYR4 2012–2018
Fluoride
1136 µg/L 28%
of the EPA limit 4000 µg/L
worst single sample: 1150 µg/L
15/15 SYR4 2012–2018
Nitrate
540 µg/L 5.4%
of the EPA limit 10000 µg/L
 14/80 SYR4 2012–2019
Dibromochloromethane
1.618 µg/L
No EPA limit set
worst single sample: 1.86 µg/L
12/30 SYR4 2012–2019
Nitrate-Nitrite
522.5 µg/L 5.2%
of the EPA limit 10000 µg/L
worst single sample: 540 µg/L
8/25 SYR4 2012–2018
Arsenic
1.953 µg/L 20%
of the EPA limit 10 µg/L
worst single sample: 2.1 µg/L
7/15 SYR4 2012–2018
Lithium
18.9 µg/L
No EPA limit set
 3/10 UCMR-5 2023
Monochloroacetic Acid
3.98 µg/L
No EPA limit set
 1/30 SYR4 2012–2019
62 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalBenzeneBeryllium, TotalBromoformChlorobenzeneCyanideCadmiumCarbon TetrachlorideChromiumDichloromethaneDibromoacetic AcidEthylbenzeneHfpo-DaMercuryMonobromoacetic AcidNetfosaaNfdhaNmefosaaNitritePfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaSeleniumStyreneTetrachloroethyleneThallium, TotalTolueneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
ANDERSON, MATT
Phone
815-748-2050
Email
[email protected]

Frequently asked questions about Dekalb

Is Dekalb tap water safe to drink?

EPA monitoring detected 18 contaminants in Dekalb'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 Dekalb's water?

EPA monitoring detected Copper, Chloroform, TTHM, Total Haloacetic Acids (HAA5), Trichloroacetic Acid, and others. The full list with the level and data source for each is above.

How many people does Dekalb serve?

Dekalb reports serving 40,290 people in Illinois, per its EPA record.

Has Dekalb had any water quality violations?

The EPA has 85 violations on file for Dekalb, of which 66 are health-based (a contaminant limit or required treatment was breached) and 0 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.