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Tap water quality report

Spearfish, SD

EPA monitoring detected 13 contaminants across the 28 water suppliers serving Spearfish. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

28
water suppliers
16,215
people served
13
contaminants found
South Dakota rankings Lead in South Dakota PFAS in South Dakota

What was found in Spearfish'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
Nitrate
2080 µg/L 21%
of the EPA limit 10000 µg/L
 16/28 SYR4
Copper
733 µg/L 56%
of the EPA limit 1300 µg/L
 24/28 SYR4
Barium
613 µg/L 31%
of the EPA limit 2000 µg/L
 20/28 SYR4
Fluoride
500 µg/L 13%
of the EPA limit 4000 µg/L
 21/28 SYR4
Nitrite
127 µg/L 13%
of the EPA limit 1000 µg/L
 1/28 SYR4
Lead
18 µg/L 120%
of the EPA limit, in the worst sample — 15 µg/L
 24/28 SYR4
TTHM
13.3 µg/L 17%
of the EPA limit 80 µg/L
 8/28 SYR4
Gross Alpha, Excl. Radon And U
10.2 pCi/L 68%
of the EPA limit 15 pCi/L
 17/28 SYR4
Selenium
9 µg/L 18%
of the EPA limit 50 µg/L
 5/28 SYR4
Arsenic
6 µg/L 60%
of the EPA limit 10 µg/L
 5/28 SYR4
Chromium
5.6 µg/L 5.6%
of the EPA limit 100 µg/L
 3/28 SYR4
Total Haloacetic Acids (HAA5)
1.5 µg/L 2.5%
of the EPA limit 60 µg/L
 2/28 SYR4
Lead
0.0050 mg/L 33%
of the EPA limit 0.0150 mg/L
 27/28 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 Spearfish

SupplierPopulation served
SPEARFISH 13,803
MOUNTAIN PLAINS 2 HOMEOWNERS ASSOC 268
SAINT ONGE SEWER & WATER CO 255
LANTERN ESTATES 192
WALNUT PARK 180
SPEARFISH VALLEY MOBILE ESTATES 163
COUNTRY ROAD ESTATES 112
KEN'S TRAILER COURT 110
WESTFIELD ADDITION 104
WESTVIEW HOMEOWNERS ASSOCIATION 103
D & E WATER COMPANY 100
SPEARFISH MEADOWS 87
LOURIE LANE HOMEOWNERS ASSOC 75
RIVERSIDE MOBILE HOME COURT 75
WILD TURKEY ESTATES II 70
SPRING CREEK PRESERVE 68
MEADOW CREST SANITARY DISTRICT 63
DEBERG WELL USERS ASSOCIATION 54
SUNRISE HOMEOWNERS ASSOCIATION 50
CENTENNIAL VISTA ESTATES 44
VALLEY VIEW WATER ASSOCIATION 42
THE TIMBERS 33
WILD TURKEY ESTATES I 33
TWO BIT RANCH ESTATES 30
REYNOLDS COURT 28
CENTENNIAL HILLS HOME ASSOCIATION 25
CHRIS' MOBILE HOME COURT 25
BICENTENNIAL TRAILER COURT 23

Frequently asked questions about Spearfish tap water

Is Spearfish tap water safe to drink?

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

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

What contaminants are in Spearfish's water?

The contaminants EPA monitoring detected in Spearfish include Nitrate, Copper, Barium, Fluoride, Nitrite. 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.