Smelly water, or rotten egg odor, is hydrogen sulfide gas that is present in the water. It is not usually harmful at the low concentration that occurs in a household water system. The City maintains a chlorine residual throughout the system that eliminates this smell, but if water sits in any place too long (dead-end lines, unoccupied houses, new developments with only a few homes), the chlorine dissipates and results in the smell. Water heaters with a magnesium anode rode are another common cause of this odor, especially in houses where little water is used. To eliminate smelly water caused by your water heater, turn your hot water heater to high for several hours (150-160 degrees). This should kill the sulfur bacteria. Then flush your system, especially your water heater. Also, the magnesium rod can be replaced with an aluminum one or removed completely. If you live on a dead-end line or in an area with just a few homes, we recommend calling the City Water Department so that the lines can be flushed to assure that there is chlorine present to kill the hydrogen sulfide odor.