Monroe Water Hardness & Quality Report (2026)
Water Hardness
2.8 grains per gallon
Source
reservoir
pH Level
7.5
neutral = 7.0
Lead
0.005 mg/L
✓ Below action level
TDS
101.3 mg/L
Est. Daily Cost
$0.13
energy & soap waste
Source: See methodology section below · Updated 2026
0–60
mg/L
Soft
61–120
mg/L
Moderately Hard
121–180
mg/L
Hard
180+
mg/L
Very Hard
Appliance Damage Report
In Monroe, your appliances are currently losing 6% efficiency due to mineral buildup.
| Appliance | In Monroe | Soft Water City | Efficiency Loss |
|---|---|---|---|
| Kettle | 8 yrs | 8.5 yrs | -6% |
| Washing Machine | 11.3 yrs | 12 yrs | -6% |
| Water Heater | 14.1 yrs | 15 yrs | -6% |
Regional Water Comparison
How Monroe compares to its nearest neighbours
| City | Hardness | PFAS (ppt) | Risk | Source |
|---|---|---|---|---|
| ▶ Monroe, Washington | 48 mg/L | 0 ppt | 🟢 Soft | reservoir |
| Maltby, Washington | ≈ 0–60 mg/L | 3.2 ppt | 🟢 Soft | reservoir |
| Cottage Lake, Washington | ≈ 60–120 mg/L | 2.4 ppt | 🟡 Moderately Hard | reservoir |
| Silver Firs, Washington | ≈ 0–60 mg/L | 2 ppt | 🟢 Soft | reservoir |
| Lake Stevens, Washington | 24 mg/L | 1.6 ppt | 🟢 Soft | groundwater |
National Benchmark
How Monroe compares to the USA average
| Benchmark | Hardness | Appliance Risk |
|---|---|---|
| ▶ Monroe | 48 mg/L | 🟢 None |
| USA National Avg | 151 mg/L | 🟠 Moderate |
| Scarsdale Top Rated | 0.02 mg/L | 🟢 None |
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What Makes Monroe's Water Unique?
Local geology and source profile
The City of Monroe Public Works Department manages the drinking water supply for Monroe, WA, in Snohomish County, serving the city and surrounding areas. Water originates from surface sources in a high-rainfall Cascade watershed, supplied via the City of Monroe Water Treatment Plant. No specific reservoir or river names are detailed in available reports, but the system relies on this protected mountain source. Hard copies of the annual Consumer Confidence Report (CCR) are available at 806 West Main St, Monroe, WA 98272, with the 2024 CCR accessible online.
The watershed is among the wettest in the continental United States, receiving approximately 165 inches of annual rainfall, feeding the supply from Cascade Range headwaters. Geology includes Tertiary granitic intrusions, volcanic flows, and metamorphic schists, with minor limestone outcrops that impart moderate mineral content. Pleistocene glacial deposits shape the alluvial fans and river valleys, promoting quick runoff with limited deep mineral dissolution and resulting in a moderately mineralised water character.
At moderately mineralised levels, practical impacts include moderate scale buildup in appliances such as dishwashers, washing machines, and water heaters, reducing efficiency over time; glassware spotting and drier skin or hair from showers may occur. Periodic vinegar descaling for faucets and heaters and using rinse aids in dishwashers help mitigate effects; a water softener is optional but recommended if scaling becomes noticeable, especially for homes with older plumbing. The 2024 CCR confirms compliance with EPA standards for pH, lead, and copper monitoring; no specific PFAS or notable contaminant exceedances are highlighted; treatment involves standard filtration, disinfection, and basic coagulation. Contact the Water Quality Office at 360.863.4515 for details.
Geology & Source: Cascade Range watershed — Tertiary granitic intrusions, volcanic flows, metamorphic schists, minor limestone outcrops; Pleistocene glacial till and alluvial deposits; limited mineral dissolution produces moderately mineralised supply
Other Washington Water Reports
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Frequently Asked Questions
Is Monroe's water safe to drink?
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How does Monroe compare to the USA average?
Data Sources & Methodology
Water quality data for Monroe is derived from geographic and geological modelling of the surrounding region. No federal monitoring station data was available for this location.
Water Hardness
Modelled estimate based on state-level USGS geological survey data for this region. No direct USGS Water Quality Portal measurement was matched to this city — the value reflects a statistical range calibrated to the state's dominant rock types and typical source water characteristics.
pH
Estimated from regional geology and source water characteristics. pH is correlated with water hardness and local bedrock — values may differ from utility-reported figures.
TDS — Total Dissolved Solids
Estimated using a derived ratio from water hardness and regional conductance profiles. TDS in natural water correlates strongly with total mineral content including hardness ions.
PFAS — Perfluoroalkyl and Polyfluoroalkyl Substances
EPA UCMR5 (5th Unregulated Contaminant Monitoring Rule, 2023–2025) — sum of PFAS compounds detected at the public water system serving this city. A value of 0 indicates the system was sampled with no detection above reporting limits.
Lead
Modelled estimate based on the EPA Lead and Copper Rule 90th-percentile tap-sample methodology. No publicly available per-city lead dataset with sufficient national coverage exists. Values are a conservative baseline derived from city population tier and infrastructure age — all estimates are maintained below the EPA action level of 0.015 mg/L.
Appliance Lifespan
Calculated from water hardness using a linear degradation model. Baseline lifespans represent soft-water performance (kettle: 8.5 yrs, washing machine: 12.0 yrs, water heater: 15.0 yrs). Hard water mineral scale progressively reduces operational life in direct proportion to hardness concentration.