Water Quality in Twain Harte, CA: 13 Violations Recorded for Mapped Water Systems
5 water systems · 1 directly mapped ZIP records
Available EPA records report 13 violations across 1 directly mapped ZIP records with known counts for Twain Harte. 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 Twain Harte
This table shows typed EPA water evidence only. Missing violation counts are displayed as N/A, not zero.
| ZIP Code | Violations | Health | |
|---|---|---|---|
| 95383 | 13 | 2 | View report → |
Water Quality Overview
Twain Harte, California has directly mapped EPA water-system data for 1 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 13 violations, including 2 health-based violations across 1 directly mapped ZIP record with reported counts.
Lead Levels
The average of the reported 90th-percentile lead results across the ZIP codes of Twain Harte is 0.0126 mg/L; the EPA action level of 0.015 mg/L applies to a water system's own 90th-percentile result and is not a safety threshold (EPA's health goal for lead is zero). No exceedances appear among the 1 ZIP records with known lead status.
With 75% of homes built before 1986, Twain Harte 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.
Water Systems Serving Twain Harte
Twain Harte is served by 5 community water systems regulated under the Safe Drinking Water Act. About 3,663 people live in the area (1 ZIP code, Census); this is not the systems' reported service population.
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
EPA records list 10 enforcement actions against water systems serving Twain Harte. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Twain Harte
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 Twain Harte Water Systems
The following contaminants have been detected or caused violations across Twain Harte's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Stage 2 DBP Rule | Treatment Technique | N/A | 5 | 1 | Yes |
| Lead | Inorganic | 0.015 mg/L | 1 | 1 | No |
| Stage 1 DBP Rule | Treatment Technique | N/A | 1 | 1 | No |
The standard column shows the EPA Maximum Contaminant Level (MCL) except for lead and copper, whose value is an action level that triggers corrective steps and is not an MCL. Health-based violations are MCL, MRDL and treatment-technique violations.
EPA Enforcement History
The EPA and state regulators have taken 4 enforcement actions against water systems serving Twain Harte. Recent actions:
| Date | Action Type |
|---|---|
| 2025-09-15 | State Order Extension |
| 2025-08-27 | State Filed Judgment |
| 2023-06-15 | State Order Extension |
| 2023-03-09 | State Filed Suit |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-09-15.
Twain Harte vs. Nearby California Cities
How Twain Harte's water quality compares to similar cities in California:
| City | Direct EPA ZIPs | Violations | Systems | Population |
|---|---|---|---|---|
| Twain Harte | 1 | 13 | 5 | 3,663 |
| Crockett | 1 | 0 | 2 | 3,665 |
| Murphys | 1 | 2 | 1 | 3,682 |
| Penngrove | 1 | 2 | 5 | 3,628 |
Common Questions About Twain Harte Water
These are the most common questions residents search for about water quality in Twain Harte, California:
Is Twain Harte water hard or soft? Water hardness varies by source. Twain Harte's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Twain Harte tap water? City-level EPA records cannot determine safety at a specific tap. The measured subset contains 2 health-based violations; check the affected utility record and consider certified testing.
What is the best water filter for Twain Harte? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Twain Harte vs. California Average
Understanding how Twain Harte 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 Twain Harte.
ZIP Codes in Twain Harte
Twain Harte spans 1 ZIP code. EPA water-system coverage is available for 1 directly mapped ZIP code. 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.