How does Fillmore's water compare to the national average?

The USA national average is 151 mg/L. Fillmore (≈ 180+ mg/L) is 189 mg/L harder than average.

Fillmore Water Hardness & Quality Report (2026)

Water Hardness

very hard

180+ mg/L

Very Hard

estimated · not lab-verified

Source

groundwater

pH Level

7.6

neutral = 7.0

Lead

0.004 mg/L

✓ Below action level

TDS

218.6 mg/L

Est. Daily Cost

$0.91

energy & soap waste

Source: See methodology section below · Updated 2026

very hard180+ mg/LVery Hard · est.

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 Fillmore, your appliances are currently losing 45% efficiency due to mineral buildup.

Appliance	In Fillmore	Soft Water City	Efficiency Loss
Kettle	4.7 yrs	8.5 yrs	-45%
Washing Machine	6.6 yrs	12 yrs	-45%
Water Heater	8.3 yrs	15 yrs	-45%

Regional Water Comparison

How Fillmore compares to its nearest neighbours

City	Hardness	Risk	Source
▶ Fillmore, California	≈ 180+ mg/L	🔴 Very Hard	groundwater
Moorpark, California	≈ 180+ mg/L	🔴 Very Hard	reservoir
Santa Paula, California	≈ 180+ mg/L	🔴 Very Hard	groundwater
Simi Valley, California	≈ 120–179 mg/L	🟠 Hard	reservoir
Camarillo, California	≈ 120–179 mg/L	🟠 Hard	reservoir

National Benchmark

How Fillmore compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ Fillmore	≈ 180+ mg/L	🔴 High
USA National Avg	151 mg/L	🟠 Moderate
Scarsdale Top Rated	0.02 mg/L	🟢 None

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What Makes Fillmore's Water Unique?

Local geology and source profile

Source: GroundwaterTDS: 218.6 mg/LpH: 7.6

The City of Fillmore Water Department draws exclusively from local groundwater wells that tap into the Santa Clara River Valley aquifer in Ventura County, California. While there are no surface reservoirs or rivers directly utilized for the municipal supply, the groundwater originates within the Santa Clara River watershed. Treatment, including disinfection and other necessary processes, takes place at city-run facilities before the water is distributed to the approximately 16,000 residents and businesses served by the Fillmore system.

Geologically, Fillmore's water originates from Quaternary alluvial fan deposits and older Tertiary sedimentary rocks like the Pico and Repetto Formations. These formations, influenced by limestone and calcareous shales within the Transverse Ranges and San Gabriel Mountains catchment areas, contribute significant dissolved calcium and magnesium. Prolonged subsurface flow through these mineral-rich strata results in naturally high mineral content and a characteristically hard water supply for the region.

This very hard water can lead to considerable scale buildup in household appliances like water heaters, dishwashers, and washing machines, often necessitating descaling every one to two years. Homeowners might notice soap scum in showers and stiffer laundry, even with extra detergent. Installing a whole-house water softener is strongly recommended to exchange calcium and magnesium ions, which helps protect plumbing and improves cleaning efficiency. Untreated scale can even hike energy bills by up to 30%.

Geology & Source: Santa Clara River Valley groundwater basin; Quaternary alluvial deposits, Tertiary sedimentary rocks, limestone, dolomite, and calcareous shales contribute to high hardness

Other California Water Reports

Moorpark

≈ 180+ mg/L

🔴 Very Hard

Santa Paula

≈ 180+ mg/L

🔴 Very Hard

Simi Valley

≈ 120–179 mg/L

🟠 Hard

Camarillo

≈ 120–179 mg/L

🟠 Hard

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Notice an error or missing data? Help us keep this page accurate. If you spot incorrect water hardness, outdated utility info, or missing details, please let us know.

All reports are reviewed by our team. Thank you for supporting data quality!

Frequently Asked Questions

Is Fillmore's water safe to drink?

Yes. Fillmore's water meets all federal safety standards. The hardness is ≈ 180+ mg/L (Very Hard), which is safe to drink. High hardness affects appliances and taste, but poses no health risk.

Do I need a water softener in Fillmore?

At ≈ 180+ mg/L (Very Hard), Fillmore's water will cause significant limescale on kettles, washing machines, and water heaters. A water softener or descaler is strongly recommended to extend appliance lifespan and reduce energy bills by up to 45%.

How does Fillmore compare to the USA average?

The USA national average is 151 mg/L. Fillmore (≈ 180+ mg/L) is 189 mg/L above the national average. The softest major city is Scarsdale at just 0.02 mg/L.

Data Sources & Methodology

Water quality data for Fillmore is derived from geographic and geological modelling of the surrounding region. No federal monitoring station data was available for this location.

Estimated

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.

Estimated

Estimated from regional geology and source water characteristics. pH is correlated with water hardness and local bedrock — values may differ from utility-reported figures.

Estimated

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.

Measured

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.

Modelled

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.

Calculated

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.