Sioux City, Iowa: Is the Tap Water Safe to Drink?
2026 EPA water quality data for 15 community water systems serving 87,475+ residents. See violations, PFAS results, lead test results, and safety grades — free.
Is Sioux City Tap Water Safe to Drink?
Sioux City has 15 community water systems. 14 of 15 graded systems meet all EPA standards (grade A or B), while 1 has recorded violations. No active health-based violations are currently open. Check individual system reports below for specifics.
Sioux City Water Quality Overview
Sioux City, Iowa is served by 15 community water systems providing water to approximately 87,475 residents. These systems draw from groundwater (14), gwudi (1) sources. Sioux City water systems have recorded 11 health-based violations in their history, though none are currently active. Including monitoring and reporting violations, there are 54 total violations on record.
Find Your Water System
Search by ZIP code to find your exact water provider and see its full EPA report.
All 15 water systems in Sioux City
Looking for water quality data across the whole state? See our full Iowa tap water safety report covering Iowa’s EPA-regulated water systems.
Sioux City Drinking Water: Frequently Asked Questions
Is Sioux City, Iowa tap water safe to drink?
Sioux City has 15 community water systems. 14 of 15 graded systems meet all EPA standards (grade A or B), while 1 has recorded violations. No active health-based violations are currently open. Check individual system reports below for specifics.
How many water utilities serve Sioux City, Iowa?
15 community water systems serve Sioux City, Iowa, providing water to approximately 87,475 people. Different neighborhoods may be served by different utilities. Enter your ZIP code at the top to find your specific provider.
Does Sioux City tap water have lead?
Lead in drinking water typically enters from old pipes and fixtures inside homes and buildings, not from the treatment plant. The EPA requires water systems to monitor for lead under the Lead and Copper Rule. Click any water system above to see its most recent 90th-percentile lead test results. Homes built before 1986 are most likely to have lead plumbing components.
What contaminants have been found in Sioux City drinking water?
EPA violation records for Sioux City water systems are listed on each utility's report page. Common regulated contaminants include disinfection byproducts (TTHMs, HAA5), coliform bacteria, nitrates, and lead. Click any utility above to see its full violation history going back 10 years.
How do I find out which water company serves my address in Sioux City?
Enter your Sioux City ZIP code in the search box at the top of this page. ClearWater will identify the specific water system serving your area and show you its EPA violation history, lead test results, and an overall safety grade. You can also check your water bill or your utility's annual Consumer Confidence Report (CCR).