Tap water in CO7, TendringSafe to drink.Very hard.
Supplied by Anglian Water. 271 samples, 18 substances, latest on 11 December 2024. Everything is inside the legal limit, and nothing comes close to it.
9.1 / 10
The tank is as full as the score. The specks are the minerals that make water hard.
What to do about it
Hard water: compare softener quotes
At 227 mg/L a softener is the only thing that stops limescale. Filters do not soften water.
It pays for itself in most homes at this hardness, through a boiler that stays efficient and appliances that last.
ZeroWater 12-Cup Ready-Pour
£40typical price
Households concerned about PFAS and heavy metals
Waterdrop 10UA Under Sink
£70typical price
High-volume under-sink filtration without RO complexity
We earn a commission if you buy through these links, at no extra cost to you. It never changes which product we put first. How we make money
What's in a glass of CO7 water
Every bubble is a substance the lab measured. The higher it floats, the closer it came to its legal limit, the dashed line at the top.
Nickel came closest to a limit, at 45% of it. 13 of 16 substances used under a quarter of theirs.
- Nickel45%
- Nitrate35%
- Fluoride29%
- Trihalomethanes15%
- Iron11%
- Selenium8%
- Antimony7%
- Aluminium6%
- Manganese6%
- Nitrite6%
- Turbidity5%
- Copper3%
- Arsenic2%
- Lead2%
- Chromium2%
- Cadmium<1%
- Coliform Bacteria none found
- E. coli none found
All 18 results as a table
| Substance | Result | Legal limit | Share of limit |
|---|---|---|---|
| Turbidity | 0.21 NTU | 4 NTU | 5% |
| Aluminium | 0.012 mg/L | 0.2 mg/L | 6% |
| Iron | 0.021 mg/L | 0.2 mg/L | 11% |
| Manganese | 0.003 mg/L | 0.05 mg/L | 6% |
| Coliform Bacteria | 0 count/100ml | Must be zero | None found |
| E. coli | 0 count/100ml | Must be zero | None found |
| Nitrate | 17.7 mg/L | 50 mg/L | 35% |
| Nitrite | 0.03 mg/L | 0.5 mg/L | 6% |
| Copper | 0.05 mg/L | 2 mg/L | 3% |
| Fluoride | 0.43 mg/L | 1.5 mg/L | 29% |
| Arsenic | 0.0002 mg/L | 0.01 mg/L | 2% |
| Cadmium | 0.00002 mg/L | 0.005 mg/L | <1% |
| Chromium | 0.00076 mg/L | 0.05 mg/L | 2% |
| Nickel | 0.00891 mg/L | 0.02 mg/L | 45% |
| Lead | 0.00016 mg/L | 0.01 mg/L | 2% |
| Antimony | 0.00036 mg/L | 0.005 mg/L | 7% |
| Selenium | 0.00309 mg/L | 0.04 mg/L | 8% |
| Trihalomethanes | 0.0146 mg/L | 0.1 mg/L | 15% |
227mg of limescale minerals in every litre
This is the water that furs up kettles
Very hard on the UK scale. It is fine to drink. It is hard on boilers, showers, skin and anything that heats water, and a jug or tap filter will not change that.
Softener quotes for CO7
Leave your details and we will email you when we can match you with installers who cover CO7. No obligation.
Request a free assessment and we'll come back to you with local installer options for your area.
100%
free, no obligation
shared only with your consent
Your river is the Tenpenny Brook, rated moderate
The Environment Agency rated the Tenpenny Brook as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by phosphate, fish and insects and other small river life. It fails the chemical test, as every river, estuary and stretch of coast in England does, because of long-lasting pollutants such as mercury, PFOS (a forever chemical) and old flame retardants.
None of this is a test of your tap water. Environment Agency record · River health across England
CO7 in short
Tap water in CO7 (Tendring) is supplied by Anglian Water in the Tendring Central zone and scores 9.1 out of 10, against an England and Wales average of 9.0. None of the 18 tested substances came close to a limit. The latest sample is from 11 December 2024.
- Nickel is the reading closest to its limit, at 45% of the 0.02 mg/L maximumIt passed with room to spare, and everything else tested sat further below its limit. See every reading
- 2nd cleanest of 7 areas tested in TendringOnly 1 area in Tendring scored higher. The best is CO11 on 9.7.
- Hard water at 227 mg/LHard starts at 180 mg/L, the point where a softener begins to pay for itself. Limescale will build up in CO7. How hardness is measured
Questions about CO7 water
Is CO7 tap water safe to drink?
Based on the latest tests, CO7 (Tendring) water scores 9.1/10, which is safe. 0 of 18 tested contaminants exceeded recommended levels. Water is supplied by Anglian Water.
What contaminants are in CO7 water?
We tested 18 contaminants in CO7 water. None exceeded recommended safe levels.
Who supplies water in CO7?
CO7 (Tendring) is supplied by Anglian Water. You can view their full profile and compliance data on our supplier page.
Is CO7 water hard or soft?
Water in CO7 (Tendring) has a hardness of 227 mg/L CaCO3, which is classified as hard. Hard water can cause limescale buildup. A water softener or filter jug may help.
Should I use a water filter in CO7?
CO7 water scored 9.1/10 with no contaminants above recommended levels. A filter is optional but can improve taste, especially if you notice a chlorine flavour. See our filter recommendations for your area.
Are there PFAS forever chemicals in CO7 water?
No PFAS (forever chemicals) result is attached to the tap-water tests for CO7, and the Environment Agency has no PFAS detections in rivers or groundwater within 10 km of it. That reflects where sampling has happened as much as the water itself.
How clean is the river near CO7?
The Environment Agency rated the Tenpenny Brook as moderate for ecological health in its 2025 assessment, meaning the river is noticeably changed by pollution or engineering. It is held back by phosphate, fish and insects and other small river life. It fails the chemical test, as every river, estuary and stretch of coast in England does, because of long-lasting pollutants such as mercury, PFOS (a forever chemical) and old flame retardants. This is a rating of the river, not of tap water in CO7, which is treated before it reaches homes.
Keep reading
- Best Water Softener UKHarvey, Kinetico, BWT, Monarch and Water2Buy compared, with real costs
- Do I Need a Water Softener?The hardness bands, the symptoms, and a postcode check
- UK Water Hardness MapIs your water hard or soft, and does it matter?
- Is UK Tap Water Safe?Everything you need to know about tap water safety in the UK
- Do I need a water softener?The hardness bands, the symptoms, and when the answer is no
- Best water softener UKHarvey, Kinetico, BWT, Monarch and Water2Buy compared
- Water softener costUnit, fitting and salt, and how long the payback takes
- Installation explainedWhere it goes, the bypass tap, the drain, DIY or plumber
- Harvey vs KineticoThe two premium twin-cylinder brands, side by side
- Softener salt guideTablet, block or granular, and how much you get through
- Salt-free softenersConditioners and electronic descalers, honestly assessed
How to test your waterBest water filtersFilter shower headsWater testing kitsUK water rankingsWater hardness checkerWater hardness map
River and groundwater readings near CO7
Environment Agency samples from rivers, groundwater and reservoirs nearby. Not your tap water. For scale they are shown against drinking water limits; rivers are judged against much stricter environmental standards, and on those every river in England fails for chemicals.
| Substance | Reading | Drinking water limit |
|---|---|---|
| Manganese | 0.1 mg/L | 0.05 mg/L |
| Arsenic | 0.063 mg/L | 0.01 mg/L |
| Turbidity | 22 NTU | 4 NTU |
| pH | 7.58 pH | None |
| Temperature | 10.3 °C | None |
| Conductivity | 586 µS/cm | None |
| Hardness (as CaCO3) | 219 mg/L | None |
| Nickel | 0.0043 mg/L | 0.02 mg/L |
| Copper | 0.0013 mg/L | 2 mg/L |
| Iron | 0.13 mg/L | 0.2 mg/L |
| Aluminium | 0.013 mg/L | 0.2 mg/L |
| Ammonia | 0.063 mg/L | 0.5 mg/L |
| Nitrate | 1.7 mg/L | 50 mg/L |
| Phosphate | 0.22 mg/L | None |
| Zinc | 0.012 mg/L | None |
| Chromium | 0.00056 mg/L | 0.05 mg/L |
| Cadmium | 0.000165 mg/L | 0.005 mg/L |
| Dissolved Oxygen | 9 mg/L | None |
Get alerts for your area
We'll email you when water quality data changes for CO7.