Water Quality in Nampa, ID: 43 Violations - Grade N/A
12 water systems · 3 directly mapped ZIP records
Available EPA records report 43 violations across 3 directly mapped ZIP records with known counts for Nampa. This is compliance evidence, not a property-level tap-water verdict.
Data: EPA Safe Drinking Water Information System (SDWIS)
Water Quality by ZIP Code in Nampa
This table shows typed EPA water evidence only. Missing violation counts are displayed as N/A, not zero.
| ZIP Code | Violations | Health | |
|---|---|---|---|
| 83686 | 30 | 14 | View report → |
| 83651 | 9 | 1 | View report → |
| 83687 | 9 | 0 | View report → |
Violation Trend
EPA violations recorded for water systems serving Nampa.
| Year | Total violations | Health-based |
|---|---|---|
| 2023 | 2 | 2 |
| 2024 | 4 | 4 |
| 2025 | 4 | 4 |
| 2026 | 1 | 1 |
Water Quality Overview
Nampa, Idaho has directly mapped EPA water-system data for 3 ZIP codes. This page reports typed compliance facts and does not relabel the multi-source Home Safety Score as a drinking-water grade.
The available EPA records report 43 violations, including 15 health-based violations across 3 directly mapped ZIP records with reported counts.
Lead Levels
The average 90th percentile lead level across Nampa water systems is 0.0047 mg/L - within EPA limits. No exceedances appear among the 3 ZIP records with known lead status.
Water Systems Serving Nampa
Nampa is served by 12 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 136,828 people across 5 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 30 enforcement actions against water systems serving Nampa. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Nampa
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels and violation history
Request your CCR - your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test - certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration - NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories - monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in Nampa Water Systems
The following contaminants have been detected or caused violations across Nampa's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Barium | Inorganic | 2 mg/L | 12 | 2 | Yes |
| Stage 2 DBP Rule | Treatment Technique | N/A | 5 | 2 | Yes |
| Lead and Copper Rule | Treatment Technique | N/A | 5 | 1 | No |
| Revised Total Coliform Rule | Microbiological | N/A | 4 | 3 | No |
| Stage 1 DBP Rule | Treatment Technique | N/A | 3 | 2 | No |
| Lead | Inorganic | 0.015 mg/L | 2 | 1 | No |
| Combined Radium | Radionuclides | 5 pCi/L | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
Violation Trend Over Time
Year-by-year EPA violations recorded for water systems serving Nampa:
| Year | Total Violations | Health-Based |
|---|---|---|
| 2023 | 2 | 2 |
| 2024 | 4 | 4 |
| 2025 | 4 | 4 |
| 2026 | 1 | 1 |
Violations have decreased from 2 in 2023 to 1 in 2026, indicating improving compliance.
EPA Enforcement History
The EPA and state regulators have taken 21 enforcement actions against water systems serving Nampa. Recent actions:
| Date | Action Type |
|---|---|
| 2026-02-27 | State Informal Enforcement |
| 2026-02-24 | State Informal Action |
| 2026-01-25 | State Informal Enforcement |
| 2026-01-22 | State Informal Action |
| 2026-01-06 | State Order Extension |
| 2025-12-15 | State Informal Action |
| 2025-11-23 | State Informal Enforcement |
| 2025-11-20 | State Informal Action |
| 2025-10-25 | State Informal Enforcement |
| 2025-10-22 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2026-02-27.
Nampa vs. Nearby Idaho Cities
How Nampa's water quality compares to similar cities in Idaho:
| City | Direct EPA ZIPs | Violations | Systems | Population |
|---|---|---|---|---|
| Nampa | 3 | 43 | 12 | 136,828 |
| Meridian | 2 | 1 | 3 | 132,571 |
| Idaho Falls | 4 | 66 | 6 | 122,947 |
| Pocatello | 4 | 22 | 5 | 82,537 |
Water Quality by ZIP Code in Nampa
EPA coverage and recorded violations can differ across Nampa's ZIP codes. Missing counts are shown as unavailable, not zero:
Common Questions About Nampa Water
These are the most common questions residents search for about water quality in Nampa, Idaho:
Is Nampa water hard or soft? Water hardness varies by source. Nampa's 12 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Nampa tap water? City-level EPA records cannot determine safety at a specific tap. The measured subset contains 15 health-based violations; check the affected utility record and consider certified testing.
What is the best water filter for Nampa? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Nampa vs. Idaho Average
Understanding how Nampa compares to the broader Idaho average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below - water quality can vary significantly even within Nampa.
ZIP Codes in Nampa
Nampa spans 5 ZIP codes. EPA water-system coverage is available for 3 directly mapped ZIP codes. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Source reporting periods vary. See each cited source for its publication schedule.