Tap Water in DL1
Darlington Zone — Northumbrian Water
Tap water in Darlington Zone, supplied by Northumbrian Water, has the character of a blended surface and groundwater supply, with no dominant mineral signature. It’s slightly hard, around the national midpoint, with a total hardness of 166 mg/L as CaCO₃.
Mineral composition
| mg/L | |
|---|---|
| Calcium | 55 |
| Magnesium | 7 |
| Sodium | 12 |
| Sulfate | 75 |
| Chloride | 13 |
| Bicarbonate | 99 |
Additional info
| Hardness | 166.29 as CaCO₃ |
| Alkalinity | 81.2 as CaCO₃ |
| pH | awaiting data |
| Conductivity | awaiting data |
| Source | Northumbrian Water |
| Data year | 2024 |
What this means
Kettle & appliances
Light limescale will accumulate in kettles and on heating elements over weeks. A periodic descale (monthly or so) will keep things in check, but it’s not urgent.
Espresso
Hardness at this level starts to affect espresso machines more noticeably. Scale will form in boilers over months, and the water’s buffering will round off some of the brighter acidity in the cup. Regular descaling becomes worthwhile.
Filter & pour-over
Filter coffee starts to lose some of its top-end brightness here. Lighter roasts will taste rounder and less distinctive than they would with softer water, though medium and darker roasts hold up well. The cup won’t be flat, but the crispest acidity is softened.
Drinking & cooking
A faint mineral taste may be noticeable if you’re paying attention. Vegetables and pulses cook normally; rice and pasta are unaffected.
Bicarbonate
Enough buffering to take the sharpest edges off mash pH and espresso acidity without flattening either: a versatile range that works well for amber ales, wheat beers, and most filter coffee and espresso preparations, providing body without masking origin character.
Get the best from your water
DL1 tap water works well for espresso, baking, and aquarium use with little or no adjustment. Brewing is within reach with salt additions. It has too much mineral content for tea and horticulture; a bottled water blend is the better route for those.
Nearby areas
Data sourced from Northumbrian Water (2024). Looking for a specific address? Look up your full postcode for the most accurate result.