Brown Tap Water: 3 Causes Associated With Hot Water

It's hard not to be shocked when you turn on the tap only to see a stream of brown water. Although brown water looks disgusting, brown water is not dangerous to drink, as the discoloration is actually just caused by too much iron in the water. This not only gives the water a brown color, but also a metallic taste. If the water coming out from your tap is only brown when the water is hot, you'll narrow down the cause of the problem significantly. Here are 3 common causes that are usually the culprit for causing the water to turn brown.

Corrosion of the Water Heater Tank

Water heater tanks are made from metal, and the inner surface of these tanks are always exposed to different water conditions. Different metals and elements within the water can slowly cause the inner surface of the water heater tank to corrode. Almost all water heater tanks have a rod inside made of either magnesium or aluminum screwed into the top of the tank. This rod is known as a sacrificial anode and is used to prevent corrosion within the water heater tank.

With time, this rod will get worn down. In fact, you can check the water heater tank yourself before calling a plumber. If you see that a large part of the sacrificial anode has been corroded away, there's a good chance that the rod is no longer functional. This allows the minerals within the water to interact with the inner surface of the water heater tank. This causes the tank to rust, and the specks of rust will come in contact with the water causing it to turn brown.

Depending on how corroded the sacrificial anode is, replacing the sacrificial anode may or may not be sufficient. If the inner surface of the water heater tank is already severely corroded, a plumber may recommend replacing the entire water heater tank.

Rust from the Inner Surface of the Pipes

If the problem cannot be found within the water heater tank, the fact that only hot water is brown can give the plumber some idea regarding which sections of the plumbing to inspect. The pipes themselves may be rusted. The rust gets carried down the plumbing when you turn on the tap for hot water. The type of material that the pipes are made of will determine whether this is a possibility. While copper pipes can corrode due to iron deposits from a rusty water heater, iron pipes will corrode naturally with time. Usually, the sediments from the corrosion will settle on the bottom of the pipes; however, changes in water pressure can stir up these sediments.

If a section of the pipes in your plumbing have corroded, the plumber will have to inspect the level of corrosion to recommend the best solution available. You can get rid of the sediments in the brown water by simply flushing the pipes if they are not corroded too severely. If there is a large amount of corrosion, you will have to replace the pipes. If replacing the pipes is your only solution, consider switching to PVC pipes instead, as they are corrosion-resistant.

A Break on the Main Plumbing System

If a plumber finds your plumbing system to be completely fine and in good condition, the problem may not lie in your home's plumbing system. Instead the murky brown water may be coming from the main plumbing system or pipeline. If there is a break in the main water pipeline, incoming water will bring clay or even rusted water into your home's plumbing system. As the water heater tank is located between the tap and the main plumbing pipeline, the sediments from the outside supply pipeline may collect within the water heater tank.

Instead of looking for a corroded sacrificial anode or a corroded water heater tank, the plumber will test the water to determine whether it contains significant levels of mud, clay or dirt. If this is the case, the plumber will generally contact the city on your behalf in order to sort out your problem.


If the water turns brown when you turn on the tap for hot water and not for cold water, you're already narrowing down the suspects that may be causing the problem. While waiting for the plumber, you can inspect the water heater tank in order to get a better idea regarding what might be the problem. Fortunately, this problem is very easy to solve, and the repairs needed tend to be rather minor. For more information, contact a company like Salinas & Sons Rooter Service.