Water hardness in Hirakata
40 mg/L soft
Tap water in Hirakata is soft: 40 mg/L (2.3 gpg · 2.2 °dH · 4 °fH).
Source: Hirakata City Waterworks, monthly water quality results FY2025 (水質検査結果 令和7年4月–令和8年3月) (2025) · data checked 2026-10-21
Range across supply zones: 35–45 mg/L.
Hirakata is supplied by its own waterworks, which in Osaka Prefecture typically buy Yodo River water, the outflow of Lake Biwa, from the Osaka Water Supply Authority and sometimes add local wells; the exact mix for Hirakata is not confirmed here. The utility's 2025 data give 39.7 mg/L CaCO₃ within a range of 35.2 to 44.5 mg/L. Limescale is mild here, appearing slowly on kettles and taps, so occasional descaling is enough.
Japanese waterworks report hardness (硬度) in mg/L CaCO₃; the standard is 300 mg/L and the target 10–100 mg/L.
Water data
| Total hardness | 40 mg/L |
|---|---|
| Utility | Hirakata City Waterworks and Sewerage Bureau (枚方市上下水道局) |
How Hirakata compares
- Tap water in Hirakata is 21 % softer than the median of the 228 cities we track in Japan (50 mg/L).
- By hardness it ranks 173 of 228 in Japan (1 = hardest); 24 % of these cities have softer water.
- In Osaka it is number 36 of 42 cities; the regional median is 42 mg/L.
- Nearest city with clearly softer water: Tondabayashi, 35 km away (17 mg/L).
- Nearest city with clearly harder water: Katano, 4 km away (56 mg/L).
Ranking of the hardest and softest water in Japan →
What it means at home
- Little or no limescale in kettles, water heaters or washing machines.
- Soap lathers easily; water does not dry skin or hair.
- Dishwasher: salt setting at minimum or off.
- No softener needed; a jug filter only changes taste.
How much salt will you use for softening?
No. Water this soft does not need softening.
Descale a coffee machine or kettle about every 6 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Hirakata
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 2 °dH |
| AEG / Electrolux | 1 |
| Beko | 1st |
| Hoover | S0 |
| LG | H0 |
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 Hirakata water hard or soft?
It is soft: 40 mg/L as CaCO₃ (2.3 gpg, 2.2 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Hirakata safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Japanese waterworks report hardness (硬度) in mg/L CaCO₃; the standard is 300 mg/L and the target 10–100 mg/L.
How many grains per gallon is Hirakata water?
2.3 gpg, equal to 2.2 °dH, 4 °fH or 40 mg/L calcium carbonate.
What dishwasher salt setting should I use in Hirakata?
For 40 mg/L (2.2 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Hirakata?
No. With soft water a softener adds nothing.
Source
Source: Hirakata City Waterworks, monthly water quality results FY2025 (水質検査結果 令和7年4月–令和8年3月) (2025). Method: figure published by the water supplier. Hirakata City Waterworks, monthly water quality results FY2025 (水質検査結果 令和7年4月–令和8年3月) · Outdated figure? Tell us