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Tap water quality report

Yankton, SD

EPA monitoring detected 13 contaminants across the 3 water suppliers serving Yankton. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

3
water suppliers
15,686
people served
13
contaminants found
South Dakota rankings Lead in South Dakota PFAS in South Dakota

What was found in Yankton's water

The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Fluoride
740 µg/L 19%
of the EPA limit 4000 µg/L
 1/3 SYR4
Nitrate
300 µg/L 3%
of the EPA limit 10000 µg/L
 1/3 SYR4
TTHM
154 µg/L 193%
of the EPA limit, in the worst sample — 80 µg/L
 3/3 SYR4
Copper
110 µg/L 8.5%
of the EPA limit 1300 µg/L
 3/3 SYR4
Total Haloacetic Acids (HAA5)
81 µg/L 135%
of the EPA limit, in the worst sample — 60 µg/L
 3/3 SYR4
Lithium
69 µg/L
No EPA limit set
 1/3 UCMR-5
Barium
12.1 µg/L 0.6%
of the EPA limit 2000 µg/L
 1/3 SYR4
Lead
6.3 µg/L 42%
of the EPA limit 15 µg/L
 3/3 SYR4
Gross Alpha, Excl. Radon And U
0.7000 pCi/L 4.7%
of the EPA limit 15 pCi/L
 1/3 SYR4
Selenium
0.6900 µg/L 1.4%
of the EPA limit 50 µg/L
 1/3 SYR4
Chromium
0.4600 µg/L 0.5%
of the EPA limit 100 µg/L
 1/3 SYR4
Antimony, Total
0.2600 µg/L 4.3%
of the EPA limit 6 µg/L
 1/3 SYR4
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 3/3 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 single worst sample on record — 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 Yankton

SupplierPopulation served
YANKTON 15,411
EAST WINDS COURT, INC. 180
TIMBERLAND PARK 95

Frequently asked questions about Yankton tap water

Is Yankton tap water safe to drink?

EPA testing detected 13 contaminants in the water serving Yankton. 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 Yankton?

3 public water suppliers report drinking-water monitoring for Yankton, South Dakota to the EPA. Each is listed above with its population served.

What contaminants are in Yankton's water?

The contaminants EPA monitoring detected in Yankton include Fluoride, Nitrate, TTHM, Copper, Total Haloacetic Acids (HAA5). The full list, with the highest level found 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.