Discolored Water and What It Means for Your Home

Discolored hot water is more than just an aesthetic issue. Typically a rusty or muddy appearance, it can be an indicator of other problems in your household plumbing—or even in your municipal water supply. While water discoloration is rarely a health concern, it can also discolor fixtures, leave a residue on clothes washed in it and spot glassware and other implements. To troubleshoot water that is less than sparkly clear, first, try to narrow down the source.

Are both cold and hot water affected?

If you’re noticing rusty or muddy cold water and hot water, this could indicate one of two possibilities.

• First, the main water supply line in your house may be rusted or corroded due to age. This will discolor all water entering the house. It’s a red flag that shouldn’t be ignored as a deteriorating supply line may rupture at any time and cause expensive water damage to the home.
• In some cases, the source of water discoloration may originate in your municipal water supply. Clay, mud or silt deposited in water mains may be stirred up by sudden extreme changes in water pressure—such as when the fire department opens up fire hydrants. Discoloration from this cause should be a temporary phenomenon that clears rapidly.

When only hot water is discolored …

This is usually traced to the water heater. Accumulation of mineral deposits inside the heater may add a rusty or muddy tinge to hot water. Annual maintenance by a qualified plumber including flushing of the water heater tank can remove sediment. It will also improve water heating performance and lower operating costs.

Internal corrosion occurring inside the water heater tank can also cause discolored hot water. Because a corroded tank may fail without warning at any time and cause indoor flooding, this is another symptom that should be evaluated by your plumber.