Water Quality in Grass Valley, CA: 2 Violations — Grade B
Grade B · Score 81/100 · 5 water systems · Updated 2026-05-03
Grass Valley's water is mostly safe. Minor violations exist but are primarily monitoring-related.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Water systems in Grass Valley, CA have accumulated 2 EPA violations across the full compliance record — a dataset that captures reportable health-based exceedances, monitoring lapses, and enforcement actions filed with the federal Safe Drinking Water Information System.
Water Quality by ZIP Code in Grass Valley
Water quality varies across Grass Valley's 2 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 95945 | B | 78 | 1 | 0 | View report → |
| 95949 | B | 83 | 1 | 0 | View report → |
Water Quality Overview
Grass Valley, California receives a water quality grade of B with an overall score of 81 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving Grass Valley have accumulated 2 EPA violations (all monitoring/reporting type). These violations are tracked across 2 ZIP codes serving approximately 54,074 people.
What Grade B Means
A grade of B indicates good compliance with EPA drinking water standards. While not perfect, Grass Valley's water systems meet the vast majority of federal requirements. Minor violations may exist but typically relate to monitoring or reporting rather than health-based standards.
Lead Levels
The average 90th percentile lead level across Grass Valley water systems is 0.0008 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 60% of homes built before 1986, Grass Valley has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Radon Risk
Grass Valley is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Grass Valley
Grass Valley is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 54,074 people across 2 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
How to Check Your Water in Grass Valley
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
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
Grass Valley vs. Nearby California Cities
How Grass Valley's water quality compares to similar cities in California:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Grass Valley | B | 2 | 5 | 54,074 |
| Lincoln | B | 1 | 2 | 54,574 |
| Rowland Heights | B | 0 | 1 | 54,660 |
| Ceres | C | 7 | 3 | 54,751 |
Common Questions About Grass Valley Water
These are the most common questions residents search for about water quality in Grass Valley, California:
Is Grass Valley water hard or soft? Water hardness varies by source. Grass Valley's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Grass Valley tap water? Grass Valley's water receives a grade of B (81/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Grass Valley? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Grass Valley vs. California Average
Understanding how Grass Valley compares to the broader California 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 Grass Valley.
ZIP Codes in Grass Valley
Grass Valley spans 2 ZIP codes. The ZIP with the lowest water quality score is 95945. Each ZIP code has its own water quality profile based on the specific water system serving that area. 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
Updated daily.
Frequently Asked Questions
Your Water is Safe — Here's How to Keep It That Way
Grade B is excellent news. Here's what proactive homeowners do to maintain water quality:
Annual Water Testing
EPA recommends annual testing even with clean water. Home test kits: $20-$50. Catches changes before they become problems.
Maintenance Filtration
A basic carbon filter removes chlorine taste and catches emerging contaminants like PFAS that aren't yet fully regulated.
Plumbing Check
Even safe city water picks up lead from home pipes. If your home was built before 1986, a one-time pipe inspection is recommended.