Sioux Falls water quality

Updated 2026-10-22 · South Dakota · Affiliate disclosure

We read 8 results from Sioux Falls’s 2025 water quality report. No results over a legal limit; 2 above a health goal or guideline.

Serves about 198,524 people · Water system ID SD4600294 · Read the district’s 2025 report (opens in a new tab)

Open this district in the water lookupCompare with your own test results, see the district map and get matched filters.

Results from the 2025 report

Each number is copied from the district’s report and links to the page it’s printed on. Where the report lists several plants, wells or purchased water, the highest is shown.

ContaminantResultHealth goalLegal limitWhat it means
Arsenichighest measured · range 1 to 1 · Lewis and Clark Regional Water System · 2025 report, page 41 ppb0.004 ppb10 ppbAbove the health goal250x the health goal
Lead90th percentile of homes tested, 0 over the action level · sampled 2024 · Customer taps · 2025 report, page 43 ppb0.2 ppb15 ppb (action level)Above the health goal15x the health goal
Antimonyhighest measured · range 0.31 to 0.31 · 2025 report, page 40.31 ppb1 ppb6 ppbBelow the health goal
Bariumhighest measured · range 0.02 to 0.02 · highest of 2 sources · 2025 report, page 40.02 ppm2 ppm2 ppmBelow the health goal
Chromium (total)highest measured · range 0.74 to 0.74 · Lewis and Clark Regional Water System, highest of 2 sources · 2025 report, page 40.74 ppbNone set100 ppbBelow the legal limit
Copper90th percentile of homes tested, 0 over the action level · sampled 2024 · Customer taps · 2025 report, page 40.1 ppm0.3 ppm1.3 ppm (action level)Below the health goal
Fluoridehighest measured · range 0.49 to 0.85 · Lewis and Clark Regional Water System, highest of 2 sources · 2025 report, page 40.85 ppm1 ppm4 ppmBelow the health goal
Lithiumhighest measured · range 42.7 to 70.9 · sampled 2023 · 2025 report, page 670.9 ppbNone setNoneNo health limit

Utility results describe the whole system, measured where water enters the pipes, not your tap. Your home’s plumbing can add lead or copper. 10 numbers we weren’t sure about are held back until a person checks.

EPA testing for PFAS and lithium

EPA’s own nationwide testing (UCMR 5) found these in Sioux Falls’s water between Aug 2023 and May 2024. These are EPA lab results, separate from the district’s report. Anything not listed was not detected.

  • Lithium70.9 ppbFound in 8 of 8 samples · highest resultAbove EPA’s health reference level of 10 ppb (a guide, not a legal limit)

Source: EPA UCMR 5 occurrence data. The highest single result is shown; one high sample doesn’t mean every glass is that high.

What you can do

Nothing here is an emergency notice: if the district has a violation, it must tell customers directly. If you’d like to lower these at your tap, these are the treatments that remove them, and the catalog shows the models certified for each. Ranking is by certified removal; commissions never change the order.

Arsenic

Found: Arsenic

What removes it: Reverse osmosis.

See filters that remove it

Lead

Found: Lead

What removes it: Certified carbon block or RO.

See filters that remove itWhat water filter removes lead?

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