Originally Posted by DarylF08
Smelly water, or rotten egg odor, is hydrogen sulfide gas that is present in the water. Water heaters with a magnesium anode rode are another common cause of this odor, especially in houses where little water is used. I'm not sure what in the water reacts with the magnesium. The magnesium rod can be replaced with an aluminum one, or removed completely (but probably not a good idea). Then flush your system, especially your water heater. Chlorine can kill the sulfur bacteria which is why your neighbor poured that down the well. Municialities typically add chlorine with some residual left that will typically take care of any of this, but you're on a well so you're on your own.