The infamous rotten egg smell comes from bacterial growth in the drains. When organic matter like hair and food gets stuck in the drain, it will begin to break down. The decomposition sight is bacteria’s favorite place to thrive. As the amount of bacteria multiplies, the rotten egg smell (actually caused by hydrogen sulfide gas) will get stronger and stronger, climbing back up your drains.
If your water smells metallic, it’s likely carrying bits of metal in the stream as well. Your main water supply line is made of strong metal pipes (either brass, copper, or galvanized steel) that are under constant pressure, causing them to break down faster than your drain lines. When this line deteriorates, specs of metal will break off and end up in your water supply, causing your water to smell and taste funny.
You might enjoy the smell of chlorine for about a minute after you’ve finished cleaning your house from top to bottom, but it’s never an inviting odor when it comes from your plumbing. If your water smells (and tastes) like swimming pool water, there’s probably too much chlorine in your water supply. It’s not dangerous to consume, but it’s not fresh water either.
The fishy odor in your water is commonly caused by barium, cadmium, and chlorine, all naturally-occurring minerals, interacting with the water. Just like chlorine, barium, cadmium, and a host of other chemicals are used to disinfect water at the treatment plant. If this smell persists for too long, give your local water authority a call.