Water hardness in Riga
1.7 mmol/L hard
Tap water in Riga is hard: 1.7 mmol/L (170 mg/L · 9.9 gpg · 9.5 °dH).
Source: SIA Rigas udens - Liguma izpildes zinojums Riga 2025 (contract performance report), p.10 table 3 (2025) · data checked 2026-10-22
SIA Rigas udens reports an average total hardness of 1.7 mmol/L (about 170 mg/L CaCO3) for the Riga city network. The figure comes from the 2025 contract performance report, where 2023, 2024 and 2025 all read 1.7, so it is an annual average rather than a street-level measurement. We did not verify the source water for this note. At this level some limescale on kettles and heating elements is the usual practical effect.
Latvian suppliers report total hardness in mmol/L.
Water data
| Total hardness | 1.7 mmol/L |
|---|---|
| Utility | SIA Rigas udens |
How Riga compares
- Tap water in Riga is 23 % softer than the median of the 3 cities we track in Latvia (2.22 mmol/L).
- By hardness it ranks 3 of 3 in Latvia (1 = hardest); 0 % of these cities have softer water.
- Nearest city with clearly harder water: Jurmala, 20 km away (3.29 mmol/L).
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 Riga
| Brand | Setting for this water |
|---|---|
| Bosch | H02 |
| Miele | 10 °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 Riga water hard or soft?
It is hard: 170 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 Riga safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Latvian suppliers report total hardness in mmol/L.
How many grains per gallon is Riga water?
9.9 gpg, equal to 9.5 °dH, 17 °fH or 170 mg/L calcium carbonate.
What dishwasher salt setting should I use in Riga?
For 170 mg/L (9.5 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Riga?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: SIA Rigas udens - Liguma izpildes zinojums Riga 2025 (contract performance report), p.10 table 3 (2025). Method: figure published by the water supplier. SIA Rigas udens - Liguma izpildes zinojums Riga 2025 (contract performance report), p.10 table 3 · Outdated figure? Tell us