Arsenic in Drinking Water - Spokane County Water District #3, WA
Spokane County Water District #3 · Mica, WA · 18,983 people served
Data: EPA SDWIS, ECHO, 2024 Consumer Confidence Report
Arsenic Data for Spokane County Water District #3
In the pinned CCR corpus used for this correction, the matched entries support one comparable condition-level measurement: 6.7 ppb against a reported reference of 10 ppb. Source violation flags are shown separately below.
Matched Source Entries
| Contaminant | Reported Level | Reported MCL | Reported Unit | Source Violation Flag | Review Status |
|---|---|---|---|---|---|
| Arsenic | 6.7 | 10 | ppb | false | Comparable entry |
Source violation flags are preserved as reported fields and have not been independently reconciled.
Health Effects of Arsenic
The EPA classifies arsenic as a Group A human carcinogen. Long-term exposure to arsenic in drinking water — even at levels below the MCL — increases the risk of bladder, lung, skin, kidney, and liver cancer. Non-cancer effects include cardiovascular disease, diabetes, skin lesions (darkening and thickening), peripheral neuropathy, and immune system suppression. Children exposed to arsenic may experience cognitive development problems.
Source: ATSDR — Arsenic Toxicological Profile; EPA.
EPA Standard
The EPA maximum contaminant level (MCL) for arsenic is 10 ppb, governed by the Arsenic Rule (2006). Water systems that exceed this limit must notify consumers and take corrective action.
What You Can Do
- Install a reverse osmosis system — the most reliable arsenic removal technology for homes
- Use a point-of-use filter certified to NSF 53 for arsenic reduction
- Have your water tested by an EPA-certified lab — especially if you use a private well
- If arsenic is naturally occurring in your area, consider whole-house treatment
- Do not rely on standard carbon filters — most do not remove arsenic
- If on a private well, test annually; arsenic levels can fluctuate seasonally
Recommended Water Filters
The most effective treatment for arsenic removal is Reverse Osmosis.
| Filter Type | Effectiveness | NSF Standard | Notes |
|---|---|---|---|
| Reverse Osmosis (RO) | 95-99% | NSF 58 | Most effective for both arsenate (As V) and arsenite (As III) |
| Adsorptive Media (iron-based) | 90-95% | NSF 53 | Effective for arsenate; may need pre-oxidation for arsenite |
| Distillation | 98%+ | NSF 62 | Very effective but impractical for large volumes |
ZIP Codes Served by This System
Check water quality for your specific ZIP code:
Related Resources
- Spokane County Water District #3 — Full Water System Profile
- Arsenic in Drinking Water — Overview
- EPA: Arsenic
Detected Levels
| Contaminant | Level Detected | EPA Limit | Status |
|---|---|---|---|
| Arsenic | 6.7 ppb | 10 ppb | Within Limit |
Recommended Water Filters
The most effective treatment for arsenic removal is Reverse Osmosis.
| Filter Type | Effectiveness | NSF Standard | Notes |
|---|---|---|---|
| Reverse Osmosis (RO) | 95-99% | NSF 58 | Most effective for both arsenate (As V) and arsenite (As III) |
| Adsorptive Media (iron-based) | 90-95% | NSF 53 | Effective for arsenate; may need pre-oxidation for arsenite |
| Distillation | 98%+ | NSF 62 | Very effective but impractical for large volumes |