Tustin Water Hardness & Quality Report (2026)
Water Hardness
7.8 grains per gallon
Source
mixed
pH Level
7.9
neutral = 7.0
Lead
0.006 mg/L
✓ Below action level
TDS
367.2 mg/L
Est. Daily Cost
$0.36
energy & soap waste
Source: USGS Water Quality Portal · 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 Tustin, your appliances are currently losing 18% efficiency due to mineral buildup.
| Appliance | In Tustin | Soft Water City | Efficiency Loss |
|---|---|---|---|
| Kettle | 5.2 yrs | 8.5 yrs | -39% |
| Washing Machine | 8.6 yrs | 12 yrs | -28% |
| Water Heater | 10.2 yrs | 15 yrs | -32% |
Regional Water Comparison
How Tustin compares to its nearest neighbours
| City | Hardness | PFAS (ppt) | Risk | Source |
|---|---|---|---|---|
| ▶ Tustin, California | 134 mg/L | 5.8 ppt | 🟠 Hard | mixed |
| North Tustin, California | 134 mg/L | 5.8 ppt | 🟠 Hard | mixed |
| Santa Ana, California | 76.5 mg/L | 4.1 ppt | 🟡 Moderately Hard | mixed |
| Tustin Legacy, California | 146.5 mg/L | 6.1 ppt | 🟠 Hard | mixed |
| Orange, California | 45.5 mg/L | 3.2 ppt | 🟢 Soft | mixed |
National Benchmark
How Tustin compares to the USA average
| Benchmark | Hardness | Appliance Risk |
|---|---|---|
| ▶ Tustin | 134 mg/L | 🟠 Moderate |
| USA National Avg | 150 mg/L | 🟠 Moderate |
| Badger Top Rated | 8.5 mg/L | 🟢 None |
Bring Badger-quality water to your Tustin home
Shop water softeners on Amazon.com →
What Makes Tustin's Water Unique?
Local geology and source profile
Tustin, California, in central Orange County adjacent to Santa Ana and Irvine (former site of Tustin Air Station), draws its municipal water supply through the Tustin Water Services Division, sourcing from the Orange County Water District (OCWD) groundwater basin — pumping from the Orange County Basin alluvial aquifer — and from Metropolitan Water District (MWD) imported water via the Municipal Water District of Orange County (MWDOC). Water hardness in Tustin measures 134 mg/L — classified as moderately hard.
Tustin's moderately hard supply reflects the central Orange County groundwater zone character. The OCWD groundwater basin in the Tustin–Santa Ana area draws from deeper sections of the Orange County alluvial basin — the Quaternary to Pliocene alluvial fan deposits of the Santa Ana River. In the Tustin zone, wells may tap deeper, more mineralized alluvial units compared to the western OCWD service area (Westminster: 78 mg/L). The Santa Ana River alluvial fan in central Orange County is recharged partly by the Santiago Creek and local Saddleback Valley drainage — areas with somewhat higher mineral content from the Santa Ana Mountains Peninsular Ranges granodiorite and sedimentary uplift. The MWD import component (Colorado River blend) also adds to the central Orange County hardness.
At 134 mg/L, Tustin residents encounter moderate scale accumulation. Faucet aerators and showerheads develop deposits after several months — monthly cleaning with citric acid solution is practical maintenance. Dishwashers produce cleaner glassware with rinse-aid. Tustin Water Services Division and OCWD consistently deliver water meeting all California SWRCB and EPA Safe Drinking Water Act requirements.
Geology & Source: Mixed supply from Orange County Water District (OCWD) groundwater basin and Metropolitan Water District (MWD) imports via the Tustin Water Services Division — the Orange County–Main San Gabriel Basin alluvial aquifer in central Orange County; moderately hard supply at 134 mg/L in central Orange County near Santa Ana.