Brown water from the tap: what it means, and the mistake that makes it worse

Brown water from the tap looks alarming and is usually temporary. But not always — sometimes it is the first sign that a water heater or a run of old pipe is on its way out. Three quick questions tell you which, and there is one common mistake that turns a free problem into a paid one.

Brown water from the tap: hot, cold, or both?

• Only the hot water is brown. The cause is almost certainly the water heater — sediment stirred up from the bottom of the tank, or the inside of an older tank starting to rust through. That is not a water supply problem at all.
• Both hot and cold are brown. The cause is on the supply side: either the main in the street or the pipes in your house.

Question two: every faucet, or one?

If brown water from the tap comes out of one faucet only and the rest run clear, the problem is on that branch or at that fixture. If the whole house is affected, it is the supply coming in.

Question three: is it just you?

Ask a neighbor. If they have brown water from the tap too, the cause is in the street — main flushing, a main break, work on the mains, or a fire hydrant being opened nearby. Each of those stirs up sediment that has settled in the main, and it reaches every house on the line.

Brown water from main flushing is often scheduled

Many water suppliers flush their mains on a schedule. White Plains publishes its own: the city flushes neighborhood by neighborhood once a year, between midnight and 4am. September covers Battle Hill, Church Street and North Broadway. October covers Fisher Hill, Westminster, Woodcrest and the central business district. November covers Prospect Park, Highland and Carhart. April and May cover the Soundview, Gedney Farms, Colonial, Havilands, North Street, Saxon Wood and Rosedale areas, among others.

If you are in one of those areas in the right month and the water ran brown overnight, that is very likely the reason. Check your own supplier’s notices for the same kind of schedule elsewhere.

The mistake that makes it worse

When brown water from the tap comes through, run the cold water until it clears before you run any hot. White Plains says it plainly in its own advice: run the hot first and the discolored water goes into your water heater tank, and then you have to run the hot until it clears as well. It is an easy way for a free, temporary problem to turn into a longer one.

• Run a cold faucet on the lowest floor for several minutes, until it is clear.
• Do not wash whites until the water has cleared — the sediment stains fabric.
• If the hot comes out brown afterward, the tank took some in. Flushing the water heater usually takes care of it.

When brown water from the tap is your own pipes

If the water is brown first thing in the morning and clears after running for a minute, and the neighbors are fine, look at your own plumbing. In older houses here that pattern usually means galvanized steel pipe rusting from the inside. It tends to come with water pressure that has been getting slowly worse for years, and the honest fix is repiping rather than a filter.

When to call about brown water from the tap

• Only the hot water is brown and it keeps happening — that is the water heater, and an older tank that is rusting inside is close to the end. See water heater repair.
• Running the cold for a good while does not clear it, and the neighbors are fine.
• It comes with a drop in pressure, or started after work on your own plumbing.
• There is water in the street as well — that is a water main break, and the call goes to the water supplier first.

For anything about whether the water is safe to drink, ask your water supplier — they test it and they will know whether there is a notice in force. In Yonkers, that is the city’s own Water Bureau laboratory, which answers water quality complaints and tests residents’ water on request: 914-377-6764.

KBD Plumbing & Heating works across lower Westchester — Dobbs Ferry, Hastings-on-Hudson, Irvington, Yonkers, White Plains and the rest. Licensed and insured, price agreed before work starts, and the phone is answered any hour including holidays: (914) 233-3000.

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