Sioux City Tap Water Quality Report
Sioux City's water has 8 contaminants above EPA MCLGs. We recommend using a certified water filter.
Water system
SIOUX CITY WATER SUPPLY
People Served
85,797
Health-based violations since 2020
0
SIOUX CITY WATER SUPPLY. EPA SDWA violation data as of Q2 2026 (downloaded 2026-07-09).
Latest sample on file
May 2025 · SIOUX CITY WATER SUPPLY
Utilities publish newer results in their annual water quality report (Consumer Confidence Report).
Is Sioux City Tap Water Safe to Drink?
We strongly recommend using a certified water filter to reduce exposure: Sioux City's water has 8 contaminants above EPA health-based guidelines. Check our filter recommendations below for NSF-certified options that can remove the specific contaminants found in Sioux City's water.
SIOUX CITY WATER SUPPLY, Sioux City's water system, serves 85,797 people. Water quality testing is conducted regularly and reported to the EPA. The latest sample on file for SIOUX CITY WATER SUPPLY is from May 2025.
In EPA's 2023–2026 UCMR 5 testing, SIOUX CITY WATER SUPPLY measured lithium at up to 240 µg/L, which EPA counts as above its health reference level of 10 µg/L. That level is a screening value EPA uses to decide what to study further, not a legal limit, and this result does not change this page's water-quality summary.
Boil water advisories are issued by water systems and state agencies, and they change from day to day. Boil water advisories in Iowa
Sioux City Water Service Areas
What these numbers actually mean for Sioux City, IA
We read Sioux City, IA’s published record and send you a short report — which findings warrant a decision, which to ignore, and what to do about it. Including when the answer is nothing.
- 8 contaminants above EPA MCLGs and 6 contaminants with an EPA health goal detected in some samples (no level on file)
- 84 results on file
- 24 PFAS compounds on record
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Recommended Water Filters for Sioux City
Based on Sioux City's water quality data, these NSF-certified filters are recommended to remove contaminants above EPA MCLGs.
AquaTru
Classic
NSF Certified:
Flow Rate
0.04 gpm
Daily Production
600 gpd
Highlights:
- Best overall contaminant reduction score
- Most performance certifications
- Lifetime warranty
- NSF-42, NSF-53, NSF-58, NSF-401 certified
Removes 23 contaminants:
+18 more
Molybdenum, Barium, Chlorine, Arsenic, 83+ contaminants, Calcium, Chloride, Copper, Magnesium, Nitrate, Phosphorus, Sodium, Sulfate, Total Dissolved Solids, Zinc, Total THMs, Chloroform, Nitrate (as N)
AquaTru
Carafe
NSF Certified:
Flow Rate
0.3 gpm
Daily Production
4 gpd
Highlights:
- Verified PFAS reduction
- Glass collection vessel
- Plug-and-play installation
- NSF-53, NSF-42, NSF-58, NSF-401, NSF-372 certified
Removes 17 contaminants:
+12 more
Arsenic, 83+ contaminants, Copper, Total THMs, Chloroform, Chloride, Sulfate, Nitrate (as N), Molybdenum, Barium, Strontium, Uranium
Waterdrop
G3 P600
NSF Certified:
Flow Rate
600 gpm
Daily Production
600 gpd
Highlights:
- Space-saving design
- Good contaminant reduction
- NSF-58 certified
Removes 4 contaminants:
Waterdrop
G3 P800
NSF Certified:
Flow Rate
800 gpm
Daily Production
800 gpd
Highlights:
- High water production rate
- Modern design
- No tank needed
- NSF-42, NSF-53, NSF-58, NSF-372 certified
Removes 15 contaminants:
+10 more
Chlorine, Copper, Manganese, Potassium, Selenium, Total Dissolved Solids, Nitrate, Chloride, Sodium, Strontium
Filters for what Sioux City reported
Verify Your Water Quality with Independent Testing
With 8 contaminants above EPA MCLGs and 6 contaminants with an EPA health goal detected in some samples (no level on file), independent laboratory testing provides a second opinion and can track changes over time.
SimpleLab
Advanced Home Water Test
$269
Comprehensive water analysis testing over 200 contaminants including bacteria, heavy metals, and chemical compounds.
Tap Score
PFAS Forever Chemicals Test
$339.95
Specialized test for PFOA, PFOS, and 24 other forever chemicals. Essential for areas near military bases, airports, or industrial sites.
Tap Score
Haloacetic Acids (HAA9) Test
$275
Tests for disinfection byproducts formed when chlorine reacts with organic matter in water treatment.
With 8 contaminants above health guidelines, you may want to explore water purification options. Learn how to make distilled water at home for applications like humidifiers, CPAP machines, and baby formula.
What Sioux City's water readings can explain
Utility-reported data for Sioux City includes a chlorine-based disinfectant — the readings behind these common tap water questions. We publish a city-level hardness figure for Sioux City, resolved from its water systems where they report one and estimated from county sampling where they do not. Each page starts with the hot-tap and cold-tap check, then shows what your own water system reported.
On a private well near Sioux City? Public-water results do not apply to private wells. See Woodbury County well water testing and USGS risk data — modeled arsenic, nitrate, and the tests to run.
Water softener cost and installation in Sioux City
Sioux City's tap water measures 10.7 grains per gallon (183.0 mg/L) — very hard on the USGS scale, the range where scale on fixtures and appliances is the usual complaint.
Water softener cost for 10.7 gpg water in Sioux City — equipment and local installation labour for your ZIP code, with the sizing arithmetic shown in full. For the national picture first, read what a water softener costs — equipment, installation labour and ten-year ownership, each separated out. For Iowa as a whole, read water softener cost in Iowa — priced against the plumber wage published for the state.
Frequently Asked Questions About Sioux City Tap Water
Sioux City's water has 8 contaminants above EPA MCLGs. We strongly recommend using a certified water filter to reduce exposure to these contaminants. Check our filter recommendations below for NSF-certified options that can remove the specific contaminants found in Sioux City's water.
Spotted something off on this page?
Residents keep our data honest.
This form corrects our data; it does not reach SIOUX CITY WATER SUPPLY. For a problem with your water now (discolored water, no water, low pressure, a leak), contact SIOUX CITY WATER SUPPLY directly.
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