Water hardness in Marina
12 gpg very hard
Tap water in Marina is very hard: 12 gpg (205 mg/L · 11.5 °dH · 20.5 °fH).
Source: California SWRCB Division of Drinking Water, EDT lab results, system CA2710017 (2025-07) · data checked 2026-10-19
Range across supply zones: 188–266 mg/L.
The figure is for the Marina Coast Water District, from State Water Resources Control Board lab results. The median of 18 results from 2021 to 2025, taken at 3 well points, is 205 mg/L as CaCO3 (12.0 gpg), with a range of 188.2 to 266 mg/L. This is very hard water. Scale builds quickly on heaters and fixtures.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 12 gpg |
|---|---|
| Utility | Marina Coast Water District |
How Marina compares
- Tap water in Marina is 32 % harder than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 512 of 1372 in the United States (1 = hardest); 62 % of these cities have softer water.
- In California it is number 117 of 336 cities; the regional median is 9.5 gpg.
- Nearest city with clearly softer water: Monterey, 12 km away (9.3 gpg).
- Nearest city with clearly harder water: Salinas, 12 km away (15.8 gpg).
Ranking of the hardest and softest water in the United States →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Marina
| Brand | Setting for this water |
|---|---|
| Bosch | H03 |
| Miele | 11 °dH |
| AEG / Electrolux | 3 |
| Beko | 3rd |
| Hoover | S2 |
| LG | H2 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Marina water hard or soft?
It is very hard: 205 mg/L as CaCO₃ (12 gpg, 11.5 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Marina safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
How many grains per gallon is Marina water?
12 gpg, equal to 11.5 °dH, 20.5 °fH or 205 mg/L calcium carbonate.
What dishwasher salt setting should I use in Marina?
For 205 mg/L (11.5 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Marina?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: California SWRCB Division of Drinking Water, EDT lab results, system CA2710017 (2025-07). Method: own measurement. California SWRCB Division of Drinking Water, EDT lab results, system CA2710017 · Outdated figure? Tell us