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tapwater
England and Wales average 9.0

Tap water in SO31, FarehamSafe to drink.Very hard.

Supplied by Southern Water. 18,608 samples, 25 substances, latest on 29 April 2026. Everything is inside the legal limit. One result, nitrate, sits close to the line.

Get softener quotes for SO31See everything that was tested

9.3 / 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 276 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.

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£550typical price

Removes nitrate, the result that stood out in SO31.

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Removes nitrate, the result that stood out in SO31.

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What's in a glass of SO31 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.

Nitrate came closest to a limit, at 84% of it. 20 of 21 substances used under a quarter of theirs.

0%25%50%75%limitLegal limitCopper: 0.0133 mg/L, <1% of the 2 mg/L limitCopper<1%Nitrite: 0.004 mg/L, <1% of the 0.5 mg/L limitNitrite<1%Lead: 0.00009 mg/L, <1% of the 0.01 mg/L limitLead<1%Chromium: 0.001 mg/L, 2% of the 0.05 mg/L limitChromium2%Selenium: 0.0008 mg/L, 2% of the 0.04 mg/L limitSelenium2%Cadmium: 0.00012 mg/L, 2% of the 0.005 mg/L limitCadmium2%Boron: 0.0319 mg/L, 3% of the 1 mg/L limitBoron3%Turbidity: 0.13 NTU, 3% of the 4 NTU limitTurbidity3%Manganese: 0.00178 mg/L, 4% of the 0.05 mg/L limitManganese4%Nickel: 0.00077 mg/L, 4% of the 0.02 mg/L limitNickel4%Antimony: 0.0002 mg/L, 4% of the 0.005 mg/L limitAntimony4%Bromate: 0.0004 mg/L, 4% of the 0.01 mg/L limitBromate4%Mercury: 0.00004 mg/L, 4% of the 0.001 mg/L limitMercury4%Iron: 0.00928 mg/L, 5% of the 0.2 mg/L limitIron5%Fluoride: 0.08 mg/L, 5% of the 1.5 mg/L limitFluoride5%Aluminium: 0.0113 mg/L, 6% of the 0.2 mg/L limitAluminium6%Ammonia: 0.039 mg/L, 8% of the 0.5 mg/L limitAmmonia8%Arsenic: 0.001 mg/L, 10% of the 0.01 mg/L limitArsenic10%Trihalomethanes: 0.0103 mg/L, 10% of the 0.1 mg/L limitTrihalomethanes10%Colour: 3 mg/L Pt/Co, 15% of the 20 mg/L Pt/Co limitColour15%Nitrate: 41.8 mg/L, 84% of the 50 mg/L limitNitrate84%
  1. Nitrate84%
  2. Colour15%
  3. Trihalomethanes10%
  4. Arsenic10%
  5. Ammonia8%
  6. Aluminium6%
  7. Fluoride5%
  8. Iron5%
  9. Antimony4%
  10. Bromate4%
  11. Mercury4%
  12. Nickel4%
  13. Manganese4%
  14. Turbidity3%
  15. Boron3%
  16. Cadmium2%
  17. Chromium2%
  18. Selenium2%
  19. Lead<1%
  20. Nitrite<1%
  21. Copper<1%
  • Coliform Bacteria none found
  • E. coli none found
  • pH 7.9 pH
  • Conductivity 555 µS/cm
All 25 results as a table
SubstanceResultLegal limitShare of limit
Nitrate41.8 mg/L50 mg/L
84%
Coliform Bacteria0 count/100mlMust be zeroNone found
E. coli0 count/100mlMust be zeroNone found
Colour3 mg/L Pt/Co20 mg/L Pt/Co
15%
Turbidity0.13 NTU4 NTU
3%
pH7.9 pHNo legal limit–
Aluminium0.0113 mg/L0.2 mg/L
6%
Iron0.00928 mg/L0.2 mg/L
5%
Manganese0.00178 mg/L0.05 mg/L
4%
Lead0.00009 mg/L0.01 mg/L
<1%
Conductivity555 µS/cmNo legal limit–
Ammonia0.039 mg/L0.5 mg/L
8%
Nitrite0.004 mg/L0.5 mg/L
<1%
Copper0.0133 mg/L2 mg/L
<1%
Arsenic0.001 mg/L0.01 mg/L
10%
Cadmium0.00012 mg/L0.005 mg/L
2%
Chromium0.001 mg/L0.05 mg/L
2%
Nickel0.00077 mg/L0.02 mg/L
4%
Antimony0.0002 mg/L0.005 mg/L
4%
Selenium0.0008 mg/L0.04 mg/L
2%
Trihalomethanes0.0103 mg/L0.1 mg/L
10%
Bromate0.0004 mg/L0.01 mg/L
4%
Boron0.0319 mg/L1 mg/L
3%
Fluoride0.08 mg/L1.5 mg/L
5%
Mercury0.00004 mg/L0.001 mg/L
4%

276mg of limescale minerals in every litre, typical for the SO area. SO31 has no reading of its own.

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.

Soft400 mg/L

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Outside your tap

Your estuary is the Southampton Water, rated moderate

The Environment Agency rated the Southampton Water as moderate for ecological health in its 2025 assessment, meaning the estuary is noticeably changed by pollution or engineering. It is held back by nitrogen. 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

Within 10 km

106

forever-chemical detections in nearby rivers and groundwater

At 3 sites. The highest was PFOS at 0.0059 µg/L, at RSN1377 West Common Stream at Imber Way, 4.8 km away, in October 2025. These are river and borehole samples, not tests of your tap water.

Every PFAS sample around Southampton · Which filters remove PFAS · PFAS explained

SO31 in short

Tap water in SO31 (Fareham) is supplied by Southern Water in the Fareham Central zone and scores 9.3 out of 10, against an England and Wales average of 9.0. 1 of 25 tested substances was close to or over a limit. The latest sample is from 29 April 2026.

  • Nitrate is within its legal limit but flagged, at 84% of the 50 mg/L maximumAnything over three quarters of a limit is flagged here as worth watching. It has not gone over. See every reading
  • The cleanest tap water of the 4 areas tested in FarehamSO31 scores 9.3 out of 10, ahead of PO14 in second place on 9.2.
  • Very hard water at 276 mg/LThe threshold for very hard is 250 mg/L. Expect visible limescale on taps and in kettles across the SO postcode area. How hardness is measured

Next door

PO149.2 out of 10PO168.4 out of 10PO178.8 out of 10SO309.3 out of 10 · 276 mg/L

Questions about SO31 water

Is SO31 tap water safe to drink?

Based on the latest tests, SO31 (Fareham) water scores 9.3/10, which is safe. 1 of 25 tested contaminants exceeded recommended levels. Water is supplied by Southern Water.

What contaminants are in SO31 water?

We tested 25 contaminants in SO31 water. 1 were flagged, including Nitrate. PFAS (forever chemicals) were also measured in rivers and groundwater within 10 km, though not in the tap-water tests themselves.

Who supplies water in SO31?

SO31 (Fareham) is supplied by Southern Water. You can view their full profile and compliance data on our supplier page.

Is SO31 water hard or soft?

No hardness reading has been published for SO31 itself. Across the SO postcode area the typical value is 276 mg/L CaCO3, which is classified as very hard. Hard water can cause limescale buildup. A water softener or filter jug may help.

Should I use a water filter in SO31?

With 1 contaminant above recommended levels in SO31, a water filter could help. A reverse osmosis or activated carbon filter is recommended for PFAS removal. See our filter recommendations for your area.

Are there PFAS forever chemicals in SO31 water?

The tap-water tests we hold for SO31 do not include a PFAS result. Environment Agency monitoring found PFAS in 106 river and groundwater samples from 3 sites within 10 km of SO31, the highest being PFOS at 0.0059 µg/L about 4.8 km away. These are environmental samples, not tests of tap water. The UK currently has no legal limit for PFAS in drinking water; the Drinking Water Inspectorate uses a 0.1 µg/L guideline for individual compounds. Reverse osmosis filters can reduce PFAS levels.

How clean is the estuary near SO31?

The Environment Agency rated the Southampton Water as moderate for ecological health in its 2025 assessment, meaning the estuary is noticeably changed by pollution or engineering. It is held back by nitrogen. 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 estuary, not of tap water in SO31, which is treated before it reaches homes.

Keep reading

PFAS explainedNitrate levelsHow to test your waterBest water filtersFilter shower headsWater testing kitsUK water rankingsWater hardness checkerWater hardness map

River and groundwater readings near SO31

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.

SubstanceReadingDrinking water limit
Temperature7.1 °CNone
Ammonia0.14 mg/L0.5 mg/L
Nitrate2.9 mg/L50 mg/L
Nitrite0.022 mg/L0.5 mg/L
Phosphate0.028 mg/LNone
pH7 pHNone
Zinc0.0125 mg/LNone
Copper0.0048 mg/L2 mg/L
Dissolved Oxygen9.42 mg/LNone

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We'll email you when water quality data changes for SO31.

Source: Southern 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