Stonegate Water Hardness & Quality Report (2026)
Water Hardness
16.5 grains per gallon
Source
mixed
pH Level
8
neutral = 7.0
Lead
0.007 mg/L
✓ Below action level
TDS
411.1 mg/L
Est. Daily Cost
$0.75
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 Stonegate, your appliances are currently losing 38% efficiency due to mineral buildup.
| Appliance | In Stonegate | Soft Water City | Efficiency Loss |
|---|---|---|---|
| Kettle | 1.5 yrs | 8.5 yrs | -82% |
| Washing Machine | 3.2 yrs | 12 yrs | -73% |
| Water Heater | 5 yrs | 15 yrs | -67% |
Regional Water Comparison
How Stonegate compares to its nearest neighbours
| City | Hardness | PFAS (ppt) | Risk | Source |
|---|---|---|---|---|
| ▶ Stonegate, California | 282 mg/L | 6.1 ppt | 🔴 Very Hard | mixed |
| Northwood, California | ≈ 120–179 mg/L | 6.1 ppt | 🟠 Hard | mixed |
| El Camino Real, California | ≈ 180+ mg/L | 6.1 ppt | 🔴 Very Hard | mixed |
| Oak Creek, California | ≈ 120–179 mg/L | 6.1 ppt | 🟠 Hard | mixed |
| Woodbridge, California | ≈ 120–179 mg/L | 6.1 ppt | 🟠 Hard | groundwater |
National Benchmark
How Stonegate compares to the USA average
| Benchmark | Hardness | Appliance Risk |
|---|---|---|
| ▶ Stonegate | 282 mg/L | 🔴 High |
| USA National Avg | 151 mg/L | 🟠 Moderate |
| Scarsdale Top Rated | 0.02 mg/L | 🟢 None |
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What Makes Stonegate's Water Unique?
Local geology and source profile
Stonegate Water System serves the Stonegate area of San Benito County, California. The utility operates Well 1 located at 360 Bolado Road in Tres Pinos and receives surface water allocations from San Luis Reservoir through the San Benito County Water District. The system draws from both groundwater and surface sources, blending supplies to serve its service territory. The 2023 Consumer Confidence Report filed with California's State Water Resources Control Board documents the system's water quality monitoring; customers may contact the utility directly for hardness treatment options.
The Stonegate supply area lies within the San Benito County foothills and coastal range region, where groundwater and surface water sources encounter mineral-bearing geological formations. The San Luis Reservoir surface water originates from the Sierra Nevada and Coast Ranges, while the local groundwater aquifer reflects the region's sedimentary and metamorphic geology. This geological setting produces a hard water supply, with minerals accumulated as water percolates through calcium and magnesium-rich rock strata.
At 282 mg/L (very hard), scale buildup on faucets, showerheads, and inside pipes and appliances is a serious concern. Water heaters, dishwashers, and washing machines experience reduced efficiency and shortened lifespan due to mineral deposits. Soap and detergent effectiveness is diminished, requiring higher doses for cleaning. A water softener is strongly recommended to protect plumbing infrastructure and extend appliance life, particularly for the water heater and dishwasher. The system remains committed to meeting all state and federal drinking water standards.
Geology & Source: San Benito County foothills — groundwater (Well 1, Tres Pinos) and San Luis Reservoir surface water via San Benito County Water District; calcium/magnesium-bearing formations produce very hard supply
Other California Water Reports
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Frequently Asked Questions
Is Stonegate's water safe to drink?
Do I need a water softener in Stonegate?
How does Stonegate compare to the USA average?
Data Sources & Methodology
Water quality data for Stonegate 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.