Water Quality in Black Diamond, WA: No Violations — Grade A
Grade A · Score 95/100 · 5 water systems · Updated 2026-05-03
Black Diamond's water meets all EPA standards with no health-based violations.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Unlike many metros where compliance gaps appear somewhere in the record, Black Diamond, WA holds a violation-free federal history — EPA data covers 5 local water systems and every one has cleared every applicable threshold without a single flagged event.
Water Quality by ZIP Code in Black Diamond
Water quality varies across Black Diamond's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 98010 | A | 95 | 0 | 0 | View report → |
Water Quality Overview
Black Diamond, Washington receives a water quality grade of A with an overall score of 95 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
No EPA violations have been recorded for the 5 water systems serving Black Diamond. This is a positive indicator, though it does not guarantee the absence of all contaminants — some substances (like PFAS) are not yet fully regulated.
What Grade A Means
A grade of A indicates excellent compliance with EPA drinking water standards. Black Diamond's water systems have maintained strong performance in both contaminant monitoring and regulatory compliance.
Lead Levels
The average 90th percentile lead level across Black Diamond water systems is 0.0020 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
Water Systems Serving Black Diamond
Black Diamond is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 3,120 people across 1 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 5 enforcement actions against water systems serving Black Diamond. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Black Diamond
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
EPA Enforcement History
The EPA and state regulators have taken 5 enforcement actions against water systems serving Black Diamond. Recent actions:
| Date | Action Type |
|---|---|
| 2025-09-25 | State Order Extension |
| 2024-07-29 | State Order Extension |
| 2024-07-08 | State Order Extension |
| 2024-07-01 | State Order Extension |
| 2023-05-23 | State Order Extension |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-09-25.
Black Diamond vs. Nearby Washington Cities
How Black Diamond's water quality compares to similar cities in Washington:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Black Diamond | A | 0 | 5 | 3,120 |
| Malaga | A | 0 | 2 | 3,128 |
| Hansville | C | 0 | 1 | 3,086 |
| Port Gamble | B | 0 | 1 | 3,086 |
Common Questions About Black Diamond Water
These are the most common questions residents search for about water quality in Black Diamond, Washington:
Is Black Diamond water hard or soft? Water hardness varies by source. Black Diamond's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Black Diamond tap water? Black Diamond's water receives a grade of A (95/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Black Diamond? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Black Diamond vs. Washington Average
Understanding how Black Diamond compares to the broader Washington 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 Black Diamond.
ZIP Codes in Black Diamond
Black Diamond spans 1 ZIP code. 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 A 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.