Water hardness in Cambridge (Massachusetts)
4.2 gpg moderately hard
Tap water in Cambridge (Massachusetts) is moderately hard: 4.2 gpg (72 mg/L · 4 °dH · 7.2 °fH).
Source: Cambridge Water Department 2018 Consumer Confidence Report (2018) · data checked 2026-10-19
This figure is over 3 years old; hardness may have changed.
Cambridge Water Department supplies water from the Hobbs Brook and Stony Brook reservoirs. The only hardness figure we found is 72 mg/L as CaCO3 (4.2 gpg) from one sample in the 2018 report. The utility's more recent annual report has no hardness entry, so this number is old and marked as stale. It points to soft to moderately soft water, but check with the utility for a current value.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 4.2 gpg |
|---|---|
| Utility | Cambridge Water Department |
How Cambridge (Massachusetts) compares
- Tap water in Cambridge (Massachusetts) is 54 % softer than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 1143 of 1372 in the United States (1 = hardest); 17 % of these cities have softer water.
- In Massachusetts it is number 4 of 13 cities; the regional median is 1.9 gpg.
- Nearest city with clearly softer water: Somerville, 2 km away (0.8 gpg).
Ranking of the hardest and softest water in the United States →
What it means at home
- Visible kettle scale every few weeks; vinegar or citric acid is enough.
- Water heater and washing machine: some long-term scale; a scale inhibitor slows it.
- Dishwasher: medium salt setting.
- Softener optional; pays off mainly with a gas boiler or tankless heater.
How much salt will you use for softening?
Optional. A scale inhibitor or a small softener protects the heater; soap savings are modest.
Descale a coffee machine or kettle about every 3 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Cambridge
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 4 °dH |
| AEG / Electrolux | 2 |
| Beko | 1st |
| Hoover | S1 |
| LG | H1 |
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 Cambridge (Massachusetts) water hard or soft?
It is moderately hard: 72 mg/L as CaCO₃ (4.2 gpg, 4 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Cambridge (Massachusetts) 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 Cambridge (Massachusetts) water?
4.2 gpg, equal to 4 °dH, 7.2 °fH or 72 mg/L calcium carbonate.
What dishwasher salt setting should I use in Cambridge (Massachusetts)?
For 72 mg/L (4 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Cambridge (Massachusetts)?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: Cambridge Water Department 2018 Consumer Confidence Report (2018). Method: older figure, source currently unavailable. Cambridge Water Department 2018 Consumer Confidence Report · Outdated figure? Tell us