Clean water is clean water right? If I don’t get sick when I drink it that means every one can drink it right? The truth is not everyone has the same body chemistry. Everyone has a slightly different tolerance and/or sensitivity to contaminants. This could be an allergy to something in the water but it doesn’t have to be that severe. Children are often more susceptible to contaminants in water, as are the elderly and pregnant women. In the past when water systems have been contaminated, the two populations most likely to get very sick and or die are your children and seniors. Honorable mention goes to people with weakened immune systems which are almost always at greater risk.
People with high blood pressure are at more risk to sodium in water. Sodium is typically in surface and ground water as natural and artificial salts get dissolved into the water. Sodium is sometimes added to water on purpose. when you use sodium hypochlorite as a disinfectant, the hypochlorite gets used during disinfection and the sodium remains. A lot of sodium could be added if you use a water softener. If there is a lot of hardness then there will be a lot of sodium. If you aren’t careful in monitoring hardness in your water, or in the operation of you softener then you run the risk of over softening your water and adding too much sodium.
Do not think that your water is safe because it doesn’t make dogs sick. Dogs have stronger stomach acid. The pH in a dog’s stomach is around one, compared to a pH of two in humans. That means a dog is ten times more likely to kill bacteria in the water it drinks. This lower pH enables them to eat rotten meat and yes drink contaminated water. That being said, if a water source makes a dog sick then it will definitely make you sick.
Some contaminants like lead and PCBs might not be noticed in the water while drinking. In fact they are typically in such low concentrations that they pose no risk. However, if they get ingested by food animals they accumulate in the fatty tissues and fatty liquids like milk. What may be harmless to drink directly could be very toxic in cheese or meat because the animal has been drinking that water for its entire life.
Opinions on taste and odors are as diverse as there are people. How often have you traveled to a different city and thought the tap water tasted better or worse than what you were used to? The water was clean and safe to drink, it just tasted different. Some of this is from different water sources and different treatment processes, but some of it is just our taste buds. I sometimes receive questions from the public about a specific taste or smell. When I get on site and drink some water I often can not even recognize the difference they were talking about. I still go onsite and I still test the water, partly to maintain public confidence in the water system. And partly because changes in taste and odor are indicators of contamination (even though they mean nothing 99% of the time). To put it in perspective I have never had a taste or odor complaint lead to finding contamination in the system.
Everybody reacts differently to what is in their water. Normally this difference is insignificant. Sometimes; how different people react to water quality can lead to sickness and even death. If you are making water for more than one person, these differences need to be taken into account. Just like you want someone making water for you to consider how the water might affect you.