Water hardness in Dahu
169 mg/L hard
Tap water in Dahu is hard: 169 mg/L (9.9 gpg · 9.5 °dH · 16.9 °fH).
Source: Taiwan Water Corporation open data (2026) · data checked 2026-10-21
Dahu in Miaoli County is reported at 169 mg/L as CaCO3 in Taiwan Water Corporation's 2026 open data. That is hard water. Limescale on kettles and shower fittings is a likely result. The source file does not say where the town's supply originates.
Taiwan Water Corporation reports total hardness in mg/L CaCO₃; the drinking-water standard is 300 mg/L.
Water data
| Total hardness | 169 mg/L |
|---|---|
| Utility | Taiwan Water Corporation |
How Dahu compares
- Tap water in Dahu is 34 % harder than the median of the 265 cities we track in Taiwan (126 mg/L).
- By hardness it ranks 75 of 265 in Taiwan (1 = hardest); 72 % of these cities have softer water.
- In Miaoli County it is number 4 of 18 cities; the regional median is 147 mg/L.
- Nearest city with clearly softer water: Miaoli, 16 km away (96 mg/L).
- Nearest city with clearly harder water: Renai, 52 km away (248 mg/L).
Ranking of the hardest and softest water in Taiwan →
What it means at home
- Fast scale on taps, shower screens and kettle; white spots on glassware.
- Water heater: efficiency loss and element failures within years if unprotected.
- Dry skin and dull hair after showering are common.
- Softener recommended; jug or reverse osmosis for drinking.
How much salt will you use for softening?
Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.
Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Dahu
| Brand | Setting for this water |
|---|---|
| Bosch | H02 |
| Miele | 9 °dH |
| AEG / Electrolux | 2 |
| Beko | 3rd |
| Hoover | S1 |
| 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 Dahu water hard or soft?
It is hard: 169 mg/L as CaCO₃ (9.9 gpg, 9.5 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Dahu safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Taiwan Water Corporation reports total hardness in mg/L CaCO₃; the drinking-water standard is 300 mg/L.
How many grains per gallon is Dahu water?
9.9 gpg, equal to 9.5 °dH, 16.9 °fH or 169 mg/L calcium carbonate.
What dishwasher salt setting should I use in Dahu?
For 169 mg/L (9.5 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Dahu?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Taiwan Water Corporation open data (2026). Method: figure published by the water supplier. Taiwan Water Corporation open data · Outdated figure? Tell us