Tap water quality in Cambridge

Cambridge is estimated to have very hard water (~350 mg/L CaCO₃), supplied and treated to UK drinking water standards.

Supplied by Cambridge Water · Cambridge Area E01035514 · Based on DWI laboratory analysis

Nitrates

42.87mg/L

Chlorine

0.09mg/L

Lead

0.90µg/L

Fluoride

0.16mg/L

Water hardness

Estimated

Estimated: Very Hard (~350 mg/L CaCO₃)

Based on the chalk geology in Cambridgeshire. Lab-tested data for this specific supply zone is not yet available.

Your area is likely to have hard water. This can affect skin conditions and cause limescale buildup.

Parents: nitrate levels are elevated

Consider a filter rated for nitrates when preparing infant formula, and follow NHS guidance on boiling water.

How readings compare to limits

Nitrates

42.87 mg/L

PCV / limit: 50 mg/L

Chlorine

0.09 mg/L

No UK limit · WHO guideline 5 mg/L

Fluoride

0.16 mg/L

PCV / limit: 1.5 mg/L

Lead

0.90 µg/L

PCV / limit: 10 µg/L

What these readings mean

UK drinking water is regulated under the Water Supply (Water Quality) Regulations 2016, which set a prescribed concentration value (PCV) for each substance. Cambridge Water must sample against these and report the results to the Drinking Water Inspectorate.

Nitrates in Cambridge

42.87 mg/L·UK limit 50 mg/L

Nitrates come mainly from agricultural fertiliser and sewage reaching groundwater. Healthy adults process them without difficulty; the limit exists principally to protect bottle-fed infants under six months.

Lead in Cambridge

0.90 µg/L·UK limit 10 µg/L

Water leaves the treatment works lead-free. Any lead is picked up from the pipework between the main and your tap, so the reading depends heavily on your own property — pre-1970 homes are the ones worth checking.

Fluoride in Cambridge

0.16 mg/L·UK limit 1.5 mg/L

Occurs naturally in some groundwater and is deliberately added in a minority of UK supply areas. Around 10% of England receives a fluoridated supply.

Chlorine in Cambridge

0.09 mg/L·UK limit no statutory limit

Added as a disinfectant and required to remain present through the network to keep water safe in transit. Typically 0.2–0.5 mg/L at the tap. A noticeable taste is usually harmless and fades if water stands in a covered jug.

Living with hard water in Cambridge

Cambridge's water is estimated at around 350 mg/L CaCO₃ from local geology, which would put it firmly in the hard water band. Hardness is dissolved calcium and magnesium picked up as water passes through chalk and limestone. It is not a health risk — the minerals are the same ones found in food — but it has practical consequences.

Hard water and skin — what the research says →

Common questions about Cambridge tap water

Is Cambridge tap water safe to drink?

Cambridge tap water is supplied by Cambridge Water and is treated to UK drinking water standards. Our latest figures show nitrates at 42.87 mg/L, lead at 0.90 µg/L, fluoride at 0.16 mg/L and chlorine at 0.09 mg/L, with nitrates elevated enough to be worth noting if you are preparing infant formula. Readings vary by supply zone, so check your exact postcode.

Is Cambridge hard or soft water?

Cambridge is estimated to have hard water. Based on local geology, hardness is estimated at around 350 mg/L CaCO₃, which would be classed as very hard on the UK scale. Lab CaCO₃ data for the supply zone is not yet published.

What is the water hardness in Cambridge?

Water hardness in Cambridge is estimated at around 350 mg/L CaCO₃ (very hard), based on local geology. Above roughly 200 mg/L you can expect limescale in kettles and appliances, and some people find hard water aggravates dry skin.

Who supplies the tap water in Cambridge?

Tap water in Cambridge is supplied by Cambridge Water. They are responsible for treatment, distribution and the laboratory testing reported to the Drinking Water Inspectorate.

Sewage spills in Cambridge

Official Environment Agency storm overflow data near the town centre.

Check your postcode

Look up any UK address for lab results and nearby overflows.