Why Is My Tap Water Yellow or Brown? (Delhi, 2026)

The free timing test: three questions that find the source

Do this before you call anyone or buy anything. It takes about two minutes, it costs nothing, and it narrows five possible causes down to one or two. Fill a clear glass or a white mug at each step — colour is far easier to judge against white than in a steel bucket.

• 1. Is it only the first draw, or does it keep coming? Run the tap and watch. If the water is brown for ten or twenty seconds and then runs clear, the material was sitting in the pipework near you, settled overnight or during a supply gap, and the flow lifted it. If it stays discoloured minute after minute, the source is upstream — the tank, the riser or the mains — and it is being fed continuously.
• 2. Is it every tap, or one? Check a tap in the kitchen and one in each bathroom. All taps points at something common to the whole flat: the overhead tank, the sump, the incoming supply or the building riser. One tap only points at the short branch serving that tap, or at the tap itself — a rusting nipple, an old flexible connector, or debris caught in the aerator. That is a much smaller problem.
• 3. Is it the hot side, the cold side, or both? This is the question most people skip and it is the most diagnostic of the three. Hot only means the discolouration is happening inside your geyser or in the hot pipework, not in the supply — a storage geyser whose tank has begun to corrode internally is the usual reason, and that is an appliance job. Cold only, or both takes the geyser out of the picture entirely and sends you back to the supply, the tank and the pipes.

Two more free observations worth making while you are there. Let a glassful stand for fifteen minutes: if the particles settle to the bottom and leave clearer water above, you are looking at suspended solid matter such as rust or silt. And ask a neighbour on the same stack or in the same block whether they have it too — if the whole building has it, it is the building’s supply or its tank, and it belongs with your RWA rather than with a plumber you hire for your own flat.

Rusty water from the tap: old GI pipework in older Delhi flats

If your building is a couple of decades old or more and the discolouration is a rust-orange or yellow-brown, this is the first cause to consider. It is extremely common in older Delhi flats and in older parts of the NCR.

Plumbing installed in Delhi before the general switch to CPVC and PPR pipe was largely galvanised iron — steel pipe with a zinc coating inside and out. The zinc is what keeps the steel from rusting. It does not last forever. Once it has worn through, the steel underneath is in permanent contact with water, and it does what steel does: it oxidises. Flakes and fine particles of iron oxide come loose and travel with the flow, and they are orange-brown. Where the pipe is worst, the inside also grows a rough crust that narrows the bore, which is why old GI plumbing tends to give you weak flow and discoloured water at the same time.

What it looks like in practice:

• Worst on the first draw after a gap. Overnight, or after a day away, particles settle in the horizontal runs. The first flow of the morning lifts them all at once, then it clears. That daily pattern is close to a signature.
• Worse after any interruption. When supply stops and restarts, the surge scours loose material off the pipe walls.
• Often accompanied by weak flow at the same taps, because the same corrosion is narrowing the pipe.
• Sometimes only certain taps — typically the ones fed by the oldest surviving section, where part of the flat has been re-piped and part has not.

Can you fix it yourself? Not the pipe. What you can do free is flush it properly: open the affected tap fully and let it run for a few minutes into a bucket you can use for the floor or the plants, which clears the settled material rather than dribbling it out over the day. Removing and rinsing the aerator at that tap is also worth doing, because rust flakes collect in the mesh and then keep releasing colour long after the pipe has cleared — that overlaps with our guide to low pressure in one tap only.

The real repair is replacing the corroded section, and that is a plumber’s job. Whether it is a short branch or the whole riser changes the size of it completely, which is why a plumber will want to see where the discoloured taps sit relative to the pipework before quoting. Our plumber charges guide for Delhi NCR explains what drives that kind of work; this page names no figure.

Brown water after the supply came back, or after a tanker fill

If the discolouration arrived suddenly, on a day when something happened to the supply, the cause is usually disturbance rather than decay. Nothing in your flat changed — something upstream got stirred.

• Supply resumed after a cut. Every distribution system carries fine sediment that sits quietly in the bottom of pipes while flow is steady. Stop the flow and restart it and the surge picks all of it up at once. Brown water in the hour after supply returns, clearing steadily as you run it, is the classic version of this. It is the single commonest reason for a one-off episode of discoloured water in Delhi.
• A tanker has just filled your tank or sump. A tanker delivers a large volume fast into a tank that has a layer of settled silt at the bottom. The incoming jet stirs that layer through the whole tank, and for a while everything drawn off is cloudy or brown. If your building runs on tanker supply in summer and the discolouration follows deliveries, that is your answer, and the fix is tank cleaning plus a gentler fill arrangement, not plumbing.
• Work on the mains nearby. A burst repaired, a valve operated, a new connection cut in, or hydrant use during a fire — any of these change the direction and speed of flow in the street main and scour material off the pipe walls. The tell is that the whole locality has it at once, and it clears over hours. Your RWA usually knows within a phone call whether the utility has been working in the area.
• The building pump ran the sump dry. Running a sump down to the last few inches draws off exactly the layer where silt has settled. If the discolouration follows the building pump’s cycle, mention that to whoever runs it.

What to do about the disturbed-sediment cases is mostly patience plus flushing: run the taps into buckets for a few minutes, do not run the washing machine or a light-coloured wash while it is discoloured, and check again after an hour. If it has not cleared after several hours of normal use, stop treating it as a passing episode and go to the testing and escalation section below. If your problem is that the water is not arriving at all rather than arriving discoloured, see no water in the taps.

The overhead tank and the sump: the cause people forget

In almost every Delhi flat, the water at your tap has not come straight from the main. It has been stored — usually twice, in an underground sump and then in an overhead tank on the terrace. Both are open to being dirty, and both are outside the plumbing a plumber normally looks at.

Why storage causes discolouration:

• Silt settles and then gets stirred. Fine solids that arrive with the supply drop to the bottom of a tank and stay there until something disturbs them — a fast fill, a low level, a pump kicking in. Then they go out with the draw.
• The tank itself degrades. An old steel tank rusts internally and puts colour into the water directly. A cracked or ill-fitting lid lets in dust, leaves, insects and Delhi’s ordinary airborne grit, especially through the dust storms of May and June.
• Nobody remembers when it was last cleaned. This is the honest state of most buildings. Tanks are out of sight, on a terrace nobody visits, and the interval quietly stretches to years.

How to confirm it is the tank: the discolouration affects every tap in the flat, it does not clear however long you run it, and the cold side is as bad as any. If your building has a bypass that lets you draw directly from the mains supply line, comparing that water with tank water settles the question in one glass. If your neighbours on the same tank have it and a flat on a different tank does not, that is confirmation too.

The fix is a proper tank clean — drained, scrubbed, sludge removed, rinsed, and the lid repaired or replaced so it seals. In a shared building that is an RWA matter and should be on a schedule, not done in response to complaints. Our water tank cleaning guide for Delhi covers what the job involves and what drives its cost, and our water supply and tank tips for Delhi covers the habits that keep it from getting to this point. If the water also tastes or smells different, read why water tastes bad or smells alongside this page, because taste and colour often share a cause.

Get it tested, and who to raise it with

Here is the part this page has been building to. Once you know roughly where the colour is entering, you have two separate things to do, and they go to two different places.

1. Get the water tested. Colour tells you solids are present. It does not tell you what they are, and no plumber, no salesman and no web page — including this one — can tell you from a description. A laboratory test of a sample taken from your own tap is the only thing that answers the question. Ask your RWA first, because buildings often arrange periodic testing already and you may be able to get a copy of a recent report at no cost to you. Otherwise, water testing laboratories operate across Delhi NCR; collect the sample exactly as the laboratory instructs, note whether you took it as a first draw or after running the tap, and take it in promptly.

2. Raise it with the people responsible for the supply. Which body that is depends on where you live and how your building is fed:

• Everyone in the building has it — start with your RWA or building management. Shared tanks, sumps, pumps and risers are their responsibility, not yours, and you should not be paying a plumber for them out of your own pocket.
• The whole street or colony has it — that is the water utility for your area, and your RWA will usually have the working contact and may already have logged it. Register a complaint in your own name as well, with the date, the time and what you observed, so there is a record.
• Only your flat has it — now it is your internal plumbing, and a plumber is the right call.
• Only the hot water has it — that is your geyser, not the supply.

When to call a plumber, and what to tell them. Call once you have established that the problem is inside your flat. Give them: whether it is all taps or one; whether it is hot, cold or both; whether it clears after running and how long that takes; how old the building and the pipework are, and whether any of the flat has been re-piped; when it started and whether it followed a supply interruption or a tanker fill; and whether neighbours have it too. That list turns an hour of poking around into a targeted look, and it means they arrive expecting the right kind of work.

What drives the cost of that work is set out in our plumber charges guide for Delhi NCR. This page carries no figures at all, because XpertWorker does not set any professional’s price — the plumber you choose quotes you free, before starting, and you pay them directly.