YES ! Water is one of our most plentiful resources. Its chemical formula, H20, is probably the most well known of all chemical formulas.

But do we know Water? Contaminants in Water & there impacts:

Total Coliform: Not a health threat in itself, it is used to indicate whether other potentially harmful bacteria may be present.

E. coli is a type of fecal coliform bacteria commonly found in the intestines of animals and humans. E. coli is short for Escherichia coli. The presence of E. coli in water is a strong indication of recent sewage or animal waste contamination.

Arsenic is a toxic chemical element that is naturally found in the Earth's crust in soil, rocks, and minerals. Some people who drink water containing arsenic in excess of  standard over many years could experience skin damage or problems with their circulatory system, and may have an increased risk of getting cancer.
Copper is an essential nutrient, required by the body in very small amounts. However excessive copper can be a cause of concern. Short periods of exposure can cause gastrointestinal disturbance, including nausea and vomiting. Use of water that exceeds the standards over many years could cause liver or kidney damage.

Nitrates : Infants below the age of six months who drink water containing nitrate in excess of the MCL could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue-baby syndrome. The serious illness in infants is due to the conversion of nitrate to nitrite by the body, which can interfere with the oxygen-carrying capacity of the child's blood.
Turbidity is a measure of the cloudiness of water. It is used to
indicate water quality and filtration effectiveness (e.g. whether disease causing organisms are present). Higher turbidity levels are often associated with higher levels of disease causing microorganisms such as viruses, parasites and some bacteria.