This is an article from the water quality association that is talking about some of Perceptible Water Quality Issues.
Perceptible Water Quality Issues
Your first diagnostic tools are your senses. You can, at times, see, taste, smell, and feel contaminated water. Water that is red, orange, yellow, brown, or cloudy can signal iron, rust, or other contaminants in the mains or your household plumbing. Tannins from decaying vegetation and leaves can also give water a yellow or brownish hue.
The main perceptible signs of water issues include:
Bad Taste & Smell
Cloudiness & Discoloration
Foul-smelling or bad-tasting water are signs of impurities. Here are common water odor or taste problems you might encounter:
A rotten-egg or sulfur smell or taste suggests the presence of hydrogen sulfide. That’s often caused by a certain type of bacteria in the water. Sulfates can also cause the water to taste salty. Investigate further to pinpoint the source, such as bacteria growing in drains, water heaters, wells, or on the inside of pipes.
Musty, earthy odors and tastes may signal dissolved solids. Such aromas and tastes may be caused by decaying organic matter in the plumbing or even in the source water itself.
Then there’s the smell and taste of chlorine. It’s there for disinfection to make water safer to drink and originates during the normal chlorination treatment process, but to enjoy the taste you may want to get rid of it.
If water smells or tastes like turpentine or other chemicals that might indicate the presence of methyl tertiary butyl ether (MTBE) or xylenes, byproducts of gasoline refining, paints, detergents, or inks.
Metallic smells and tastes may be a sign of mercury, lead, copper, arsenic, or iron in the water. Manganese and zinc may also cause a metallic smell or taste. These chemicals may come from the pipes themselves.