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Tap water quality report

Castlewood, SD

EPA monitoring detected 7 contaminants across the 1 water supplier serving Castlewood. 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
698
people served
7
contaminants found
South Dakota rankings Lead in South Dakota PFAS in South Dakota

What was found in Castlewood'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
7300 µg/L 73%
of the EPA limit 10000 µg/L
Main supplier: CASTLEWOOD · 698 people · 2019
1/1 SYR4
Copper
2160 µg/L 166%
of the EPA limit, at the 95th percentile of samples — 1300 µg/L
Main supplier: CASTLEWOOD · 698 people · 2019
1/1 SYR4
TTHM
40.9 µg/L 51%
of the EPA limit 80 µg/L
Main supplier: CASTLEWOOD · 698 people · 2019
1/1 SYR4
Total Haloacetic Acids (HAA5)
16.799999999999997 µg/L 28%
of the EPA limit 60 µg/L
Main supplier: CASTLEWOOD · 698 people · 2019
1/1 SYR4
Gross Alpha, Excl. Radon And U
12.935 pCi/L 86%
of the EPA limit 15 pCi/L
Main supplier: CASTLEWOOD · 698 people · 2017
1/1 SYR4
Lead
5.17499999999999 µg/L 34%
of the EPA limit 15 µg/L
Main supplier: CASTLEWOOD · 698 people · 2019
1/1 SYR4
Lead
0.0010 mg/L 6.7%
of the EPA limit 0.0150 mg/L
Main supplier: CASTLEWOOD · 698 people · 2022
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 Castlewood

SupplierPopulation served
CASTLEWOOD 698

Frequently asked questions about Castlewood tap water

Is Castlewood tap water safe to drink?

EPA testing detected 7 contaminants in the water serving Castlewood. 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 Castlewood?

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

What contaminants are in Castlewood's water?

The contaminants EPA monitoring detected in Castlewood include Nitrate, Copper, TTHM, Total Haloacetic Acids (HAA5), Gross Alpha, Excl. Radon And U. 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.