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tapwater
England and Wales average 9.0

Tap water in CF40, Rhondda Cynon TafSafe to drink.

Supplied by Dŵr Cymru Welsh Water. 568 samples, 23 substances, latest on 31 December 2024. Everything is inside the legal limit, and nothing comes close to it.

See the filter we recommendSee everything that was tested

9.4 / 10

The tank is as full as the score.

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What's in a glass of CF40 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.

Trihalomethanes came closest to a limit, at 37% of it. 19 of 20 substances used under a quarter of theirs.

0%25%50%75%limitLegal limitChromium: 0.00012 mg/L, <1% of the 0.05 mg/L limitChromium<1%Cadmium: 0.000025 mg/L, <1% of the 0.005 mg/L limitCadmium<1%Selenium: 0.00023 mg/L, <1% of the 0.04 mg/L limitSelenium<1%Antimony: 0.000055 mg/L, 1% of the 0.005 mg/L limitAntimony1%Manganese: 0.00068 mg/L, 1% of the 0.05 mg/L limitManganese1%Arsenic: 0.00023 mg/L, 2% of the 0.01 mg/L limitArsenic2%Bromate: 0.00025 mg/L, 3% of the 0.01 mg/L limitBromate3%Boron: 0.028 mg/L, 3% of the 1 mg/L limitBoron3%Copper: 0.058 mg/L, 3% of the 2 mg/L limitCopper3%Nickel: 0.00059 mg/L, 3% of the 0.02 mg/L limitNickel3%Mercury: 0.000042 mg/L, 4% of the 0.001 mg/L limitMercury4%Iron: 0.009 mg/L, 5% of the 0.2 mg/L limitIron5%Aluminium: 0.0091 mg/L, 5% of the 0.2 mg/L limitAluminium5%Nitrate: 2.61 mg/L, 5% of the 50 mg/L limitNitrate5%Turbidity: 0.27 NTU, 7% of the 4 NTU limitTurbidity7%Fluoride: 0.11 mg/L, 7% of the 1.5 mg/L limitFluoride7%Nitrite: 0.056 mg/L, 11% of the 0.5 mg/L limitNitrite11%Lead: 0.0013 mg/L, 13% of the 0.01 mg/L limitLead13%Colour: 4.6 mg/L Pt/Co, 23% of the 20 mg/L Pt/Co limitColour23%Trihalomethanes: 0.037 mg/L, 37% of the 0.1 mg/L limitTrihalomethanes37%
  1. Trihalomethanes37%
  2. Colour23%
  3. Lead13%
  4. Nitrite11%
  5. Fluoride7%
  6. Turbidity7%
  7. Nitrate5%
  8. Aluminium5%
  9. Iron5%
  10. Mercury4%
  11. Nickel3%
  12. Copper3%
  13. Boron3%
  14. Bromate3%
  15. Arsenic2%
  16. Manganese1%
  17. Antimony1%
  18. Selenium<1%
  19. Cadmium<1%
  20. Chromium<1%
  • Coliform Bacteria none found
  • Conductivity 89 µS/cm
  • E. coli none found
All 23 results as a table
SubstanceResultLegal limitShare of limit
Coliform Bacteria0 count/100mlMust be zeroNone found
Conductivity89 µS/cmNo legal limit–
E. coli0 count/100mlMust be zeroNone found
Aluminium0.0091 mg/L0.2 mg/L
5%
Manganese0.00068 mg/L0.05 mg/L
1%
Iron0.009 mg/L0.2 mg/L
5%
Colour4.6 mg/L Pt/Co20 mg/L Pt/Co
23%
Turbidity0.27 NTU4 NTU
7%
Bromate0.00025 mg/L0.01 mg/L
3%
Trihalomethanes0.037 mg/L0.1 mg/L
37%
Boron0.028 mg/L1 mg/L
3%
Lead0.0013 mg/L0.01 mg/L
13%
Antimony0.000055 mg/L0.005 mg/L
1%
Nickel0.00059 mg/L0.02 mg/L
3%
Selenium0.00023 mg/L0.04 mg/L
<1%
Chromium0.00012 mg/L0.05 mg/L
<1%
Mercury0.000042 mg/L0.001 mg/L
4%
Arsenic0.00023 mg/L0.01 mg/L
2%
Copper0.058 mg/L2 mg/L
3%
Cadmium0.000025 mg/L0.005 mg/L
<1%
Fluoride0.11 mg/L1.5 mg/L
7%
Nitrite0.056 mg/L0.5 mg/L
11%
Nitrate2.61 mg/L50 mg/L
5%

CF40 in short

Tap water in CF40 (Rhondda Cynon Taf) is supplied by Dŵr Cymru Welsh Water in the Rhondda Cynon Taf Central zone and scores 9.4 out of 10, against an England and Wales average of 9.0. None of the 23 tested substances came close to a limit. The latest sample is from 31 December 2024.

  • 9th cleanest of 10 areas tested in Rhondda Cynon Taf1 area in Rhondda Cynon Taf scored lower. The best is CF43 on 9.7.
  • Nothing tested came within 40% of its legal limitThe highest was Trihalomethanes at 37% of the 0.1 mg/L maximum. See every reading
  • Scores higher than 0 of 9 neighbouring districtsWater here is typical for the immediate area, which usually means the same treatment works and the same supply zone.

Next door

CF379.5 out of 10CF399.6 out of 10CF389.5 out of 10CF419.5 out of 10CF429.4 out of 10CF459.5 out of 10CF729.6 out of 10CF449.5 out of 10CF439.7 out of 10

Questions about CF40 water

Is CF40 tap water safe to drink?

Based on the latest tests, CF40 (Rhondda Cynon Taf) water scores 9.4/10, which is safe. 0 of 23 tested contaminants exceeded recommended levels. Water is supplied by Dŵr Cymru Welsh Water.

What contaminants are in CF40 water?

We tested 23 contaminants in CF40 water. None exceeded recommended safe levels.

Who supplies water in CF40?

CF40 (Rhondda Cynon Taf) is supplied by Dŵr Cymru Welsh Water. You can view their full profile and compliance data on our supplier page.

Should I use a water filter in CF40?

CF40 water scored 9.4/10 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 CF40 water?

No PFAS (forever chemicals) result is attached to the tap-water tests for CF40, 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.

Keep reading

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Source: Dŵr Cymru Welsh Water test results, published through the Stream Water Data Portal; rivers and PFAS from the Environment Agency. Page updated . How we score · Where the data comes from