Why is my water brown or cloudy?

Part of our tap water guide

You turn on the tap and the water is tea-coloured, or milky like a glass of cloud. Is it air, old pipes, or something at your end?

By Andrew Tomlinson, WaterKit · Last reviewed 29 October 2026

A glass of water on the counter tells you a lot, so start there. Once the water has cleared, you can also check your own tap with a 20-in-1 test strip, which has pads for iron, manganese and hardness. It does not read colour or cloudiness, and the last section says what it can and cannot show.

Why is my tap water cloudy or milky?

Usually tiny air bubbles. The DWI says white or cloudy water is normally air trapped in the water, usually when the supply has been turned off nearby, for example after a burst main or work on the network. It says air does not harm health.

The DWI's check is a glass. Pour one and watch it. If the cloudiness clears from the bottom up, it is air, and it should normally clear within 24 hours.

The DWI's discoloured water page adds that white water can also be suspended chalk, and that repeat cases are worth reporting because it helps the company find the root cause. Severn Trent says cloudiness that has not cleared after a few days may point to your plumbing. If the cloudiness is only in the hot tap, see our hot water cloudy guide.

Why is my water brown, orange or black?

Normally because sediment in older pipes has been disturbed. The DWI says brown, black or orange water is normally caused by sediments from older pipes in the network being stirred up. Examples are a burst main, valves being opened or closed, a main being brought back into use after repairs, and third parties such as the fire service using water. A yellow tint has its own guide, why is my tap water yellow.

The deposits build up for a reason. The DWI says most older mains in this country are cast iron, originally unlined, and they corrode over time and release iron particles. Some ground waters and soft surface waters carry natural iron and manganese, and in very hard water areas chalk can build up in the mains.

Sometimes the cause is nearer to home. The DWI also lists the condition of the service pipe to your property, the plumbing inside it, and an internal tank that may need cleaning. If the cause is internal, it says the discolouration is likely to last for many weeks or months.

What should I do, and for how long?

If the problem has lasted under 24 hours, the DWI says to run the tap. It says to contact your water supplier if the water also tastes or smells unusual, if it has been discoloured for more than 24 hours and is not clearing, or if it is not simply brown, black or orange. The DWI consumer pages we read give no running time in minutes, and companies differ, so follow your own company's advice.

All three suggest asking your neighbours. United Utilities and Yorkshire Water also say to keep the hot taps and appliances such as dishwashers and washing machines off until the cold water runs clear, because sediment can pass into the hot water system. The DWI suggests keeping a sample of the discoloured water in a sealed, clean glass jar in the fridge, with the date and time noted, to show the company.

Should I drink brown tap water?

Ask your water supplier first. The DWI says that if your tap water suddenly turns discoloured, you should not assume it is fit to drink until you have sought advice from your supplier. Where iron or manganese is a known local issue, it says the water is usable once the tap runs clear, unless the supplier has issued a warning notice. The DWI's 2025 annual report says iron, manganese and aluminium are rarely present at concentrations that pose a direct risk to health, but that they can cause people to reject the supply.

Why might my own tap not match the area picture?

The area figure is an average. The last stretch of pipe is yours, or your property's, and the DWI says discolouration sometimes comes from there.

Here is the area picture first. In England in 2025, water companies recorded 57,759 consumer contacts about the appearance, taste or odour of water, or 0.97 per 1,000 people, according to the DWI's annual report. Of these, 24,810 were brown, black or orange water and 7,474 were white air. The DWI says around 63 events in England involved more than one consumer seeing brown, black or orange water at the same time.

The limits are set at the tap. The Water Supply (Water Quality) Regulations 2016 set 200 micrograms per litre for iron (0.2 mg/l) and 50 micrograms per litre for manganese (0.05 mg/l). In the DWI's Annex B, 98 of 53,039 iron tests and 18 of 52,918 manganese tests in England in 2025 did not meet the standard.

Inside a property, the DWI lists the service pipe, the plumbing and, in high-rise buildings, internal booster pumps. Our loft tank guide explains one place water can sit. If only your property in the street is affected, the DWI advises a qualified plumber, registered with the Institute of Plumbing or approved by your water company.

“The area figure is only an average, and the last stretch of pipe and the plumbing inside your home belong to your property, not the network. If your water has been coloured or cloudy more than once, I would look at your own tap rather than rely on what is reported for your area.”

What can a test strip show about brown or cloudy water?

It can add readings for iron, manganese and hardness at your own tap, but it cannot tell air from chalk from rust. For discoloured water the first calls are to your water company and, if only your taps are affected, a plumber. A strip is for checking your own water once it has cleared, and the result is not a legal sample. It cannot read lead at the UK limit, so see our lead pipes guide for that. Fill a clean glass with cold water from the kitchen tap, dip one strip, wait 30 to 60 seconds and match the pads to the chart. You can also scan the QR code on the chart, or go to our free results checker, with no app or account needed. Our home testing guide covers the method. The comments below are WaterKit's own reading of the chart.

• Iron. The pad's first colour step is 1 mg/l, five times the 0.2 mg/l standard. A coloured pad indicates a high reading, and a clear pad is not a pass.
• Manganese. The first colour step, 0.05 mg/l, is the same as the 0.05 mg/l standard. On our reading of the chart, a 0.05 colour sits at the standard, and a 0.1 colour or above sits over it.
• Hardness. The DWI says chalk can build up in the mains in very hard water areas. The top step, 425, would sit in the DWI's very hard band (over 300 mg/l), though the unit basis of our pad is unconfirmed. The link to chalky flecks is our inference. Our how hard is my water guide covers hardness.
• Copper. Blue or green water is a separate matter, which Severn Trent links to higher copper levels, often from new or old copper pipework. See our blue-green stains guide.

The area figure is an average, and the DWI says discolouration sometimes comes from the service pipe or the plumbing at your own property, so your tap may differ from what is reported for your area. The iron and manganese pads matter most for brown water. A coloured iron pad, or a manganese colour of 0.1 or above, once the water has run clear would indicate metals at your own tap worth raising with your water company or a plumber. Best pack: 20 strips, enough to test once the water clears and again after pipe cleaning or any plumbing work, £5.99 (or £10.99 with a bacteria test), with free 2nd Class delivery on every order. See the kit

Your brown and cloudy water questions

Why is my tap water cloudy?

Usually air. If a glass clears from the bottom up, the DWI says it is air bubbles, and it should normally clear within 24 hours.

Why is my tap water brown?

Normally disturbed sediment from older pipes, often after a burst or work on the network. If it has lasted under 24 hours, the DWI says to run the tap. Contact your supplier if it lasts longer or does not clear.

How long should I run the tap?

The DWI pages we read give no time. United Utilities and Severn Trent say about 20 minutes at a thin flow, and Yorkshire Water says several minutes.

Is brown water from the hot tap different?

In the sources we read, no official page pins hot-tap-only brown water on a single cause. The DWI lists internal plumbing among the causes, so a plumber is the person to ask.

Who do I contact if it keeps happening?

Your water company first. The DWI says that if the explanation is not satisfactory, or the problem persists after the company has acted and you have checked your own pipes and fittings, contact the Consumer Council for Water (CCWater).

Sources

1. Drinking Water Inspectorate, Brown, black or orange water (causes, the 24 hour rule, advice before drinking; undated page; read 29 October 2026).
2. Drinking Water Inspectorate, Discoloured water (causes inside the home, sample advice, plumbers, CCWater; undated page; read 29 October 2026).
3. Drinking Water Inspectorate, White or cloudy water (air, the glass test, 24 hours, internal causes; undated page; read 29 October 2026).
4. Drinking Water Inspectorate, Water hardness / hard water (hardness bands, very hard over 300 mg/l as calcium carbonate; undated page; read 29 October 2026).
5. Drinking Water Inspectorate, Drinking Water 2025, England, consumer contacts (57,759 contacts, 24,810 brown, black or orange, 7,474 white air, 63 events, the stalled improvement, company ranking, legal instruments; read 29 October 2026) and Annex B, compliance with standards (Table 26, iron and manganese test results by company code; read 29 October 2026).
6. The Water Supply (Water Quality) Regulations 2016, Schedule 1 (iron 200 µg/l and manganese 50 µg/l at consumers' taps; read 29 October 2026).
7. United Utilities, Discoloured water and Advice to help if your water is discoloured (running time, hot taps, health comment; undated pages; read 29 October 2026).
8. Severn Trent, My water looks unusual (cloudy and discoloured water, copper; undated page; read 29 October 2026).
9. Yorkshire Water, My water looks dark brown or black (run the cold kitchen tap, jug advice, hot taps; undated page; read 29 October 2026).
10. WaterKit, Water Test Kit (20-in-1 strip, 30 to 60 second read, strips from £3.99, free 2nd Class delivery on every order) and results portal. The pad comments and the hardness comparison are WaterKit's own reading of the colour chart steps.

Contains public sector information licensed under the Open Government Licence v3.0.