Water Quality in 51101 — Sioux City, IA
EPA data for SIOUX CITY WATER SUPPLY
Data source: U.S. Environmental Protection Agency (EPA) SDWIS Last verified: March 16, 2026
Your Water System
ZIP code 51101 in Sioux City, Iowa is served by SIOUX CITY WATER SUPPLY (EPA ID: IA9778054). This system provides water to approximately 85,791 people from surface water sources.
There are 2 community water systems serving this area.
Lead & Copper in Your Water
No Lead & Copper Rule sampling data available for systems serving this ZIP code.
Violation Summary
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| May 1, 2024 | Total Trihalomethanes (TTHM) | Monitoring | Resolved |
| May 1, 2024 | Total Trihalomethanes (TTHM) | Monitoring | Unresolved |
| May 1, 2024 | Total Trihalomethanes (TTHM) | Monitoring | Unresolved |
| May 1, 2024 | Total Trihalomethanes (TTHM) | Monitoring | Resolved |
| May 1, 2024 | Haloacetic Acids (HAA5) | Monitoring | Resolved |
| May 1, 2024 | Haloacetic Acids (HAA5) | Monitoring | Unresolved |
| May 1, 2024 | Haloacetic Acids (HAA5) | Monitoring | Unresolved |
| May 1, 2024 | Haloacetic Acids (HAA5) | Monitoring | Resolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for water systems serving this ZIP code:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 4 | No |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 4 | No |
Need help with your water quality?
Call to get connected with a local professional in your area.
Call (855) 384-4856This is a free service. You will be connected with an independent service provider.
Water Systems Serving This Area
| System Name | EPA ID | Population | Source |
|---|---|---|---|
| SIOUX CITY WATER SUPPLY | IA9778054 | 85,791 | Surface water |
| BEREA HEIGHTS INC | IA9778301 | 33 | Groundwater |
What You Can Do
- Review your annual Consumer Confidence Report (CCR) — Your utility publishes this each July
- Test your home’s water — Especially if you have older plumbing (pre-1986) that may contain lead
- Stay informed — Bookmark this page to check for updates on your water quality
Need help with water testing or filtration?
Call to get connected with a local professional in your area.
Call (855) 384-4856This is a free service. You will be connected with an independent service provider.
Other Water Quality Reports in Iowa
- 50002 (Adair) — 40 violations
- 50003 (Adel) — 15 violations
- 50005 (Albion) — 3 violations
- 50006 (Alden)
- 50008 (Allerton) — 1 violation
- 50009 (Altoona) — 9 violations
- 50010 (Ames) — 6 violations
- 50020 (Anita) — 1 violation
- 50021 (Ankeny) — 3 violations
- 50022 (Atlantic)
- 50025 (Audubon)
- 50027 (Barnes City) — 4 violations
- 50028 (Baxter) — 13 violations
- 50029 (Bayard) — 7 violations
- 50032 (Berwick)
- 50034 (Blairsburg)
- 50035 (Bondurant)
- 50036 (Boone) — 3 violations
- 50039 (Bouton) — 8 violations
- 50042 (Brayton) — 3 violations
Nearby Water Quality Reports
- 57049 (North Sioux City, SD) — 6 mi
- 57038 (Jefferson, SD) — 11 mi
- 68030 (Homer, NE) — 12 mi
- 57025 (Elk Point, SD) — 22 mi
- 68055 (Rosalie, NE) — 31 mi — 3 violations
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for SIOUX CITY WATER SUPPLY (IA9778054) on EPA.gov.
Frequently Asked Questions
Is the tap water in 51101 safe to drink?
Based on EPA records, the water system serving ZIP code 51101 has only monitoring/reporting violations, which are procedural in nature. However, individual home conditions (old pipes, well water) can affect quality.
Where does 51101’s water come from?
The primary water source for this area is surface water. SIOUX CITY WATER SUPPLY serves approximately 85,791 people.
How can I get my water tested?
Contact your local water utility for a free water quality report, or hire a certified lab for independent home water testing. The EPA recommends testing annually if you use a private well.
Does 51101 have lead in the water?
No Lead and Copper Rule sampling data is currently available in EPA records for water systems serving ZIP code 51101. If you are concerned about lead, contact your water utility or have your tap water independently tested.
What is the radon risk in 51101?
Radon zone data is not available for ZIP code 51101. The EPA recommends testing all homes for radon regardless of location, as radon levels can vary significantly even within the same neighborhood.