Definition: Potable water is water that is considered safe to drink. It has been either treated, cleaned or filtered and meets your local established drinking water standards. Or, it is assumed to be reasonably free of harmful bacteria and contaminants and also considered safe to use in cooking and baking. Examples of potable water would be tap water from treated municipal water systems, or that has been UV filtered, water distilled, or purified by reverse osmosis.
Non-potable water is generally all raw water that is untreated, such as from lakes, rivers, ground water, natural springs and ground wells. Such water is not considered potable or safe to drink unless it has passed stringent testing.
Without proper water testing, a body of water carries unknown contaminants and bacteria, and is deemed to be non-potable, unless proven otherwise. Although it may taste fine, drinking such water carries uncertain health risks.
Previously treated potable water can also become contaminated and no longer considered potable or drinkable water. An example is when tested municipally treated water results show the presence of harmful contaminants, which may have leached into those reservoirs, prompting a 'boil water advisory'.
A temporary remedy is often to boil water for at least 20 minutes, to remove impurities and make it safe to drink, until further municipal water treatment testing returns favorable results, prompting the lifting of the advisory.
Tap water would once again be safe to drink.
Is bottled water considered potable and safe? Although some regulatory standards are in place regarding bottled water quality, not all are filled with water that meets these standards or regulations. In the absence of supporting lab testing results or documented treatment processes, it can be assumed that at best, bottled water may simply be tap water that has been actively carbon filtered.
However, some bottled water manufacturers do promote their brands as having been UV filtered, assuring consumers that bacteria has been removed, or it has been through a certain water distillation, or reverse osmosis process. There are certain risks when it comes to bottled water.
Unfortunately, monitoring and safety standards in many areas, have not kept pace with the market supply of bottled water to meet consumer demand. If you don't think bottled water is safe, it's time to take steps to find an alternative potable source of water.
The bottom line: Consumers need to be proactive to ensure the water they and their families are drinking is truly potable water, is safe to drink and is from a reliable source. When you're dealing with a municipal treatment plant which is subject to constant monitoring and adherence to standards, unless there is evidence to the contrary, you can rest assured that your water is drinkable.
For those living in rural areas with various water sources, the onus is on the consumer to make their water safe. The best defense is to consult with a water technician, have your existing tap water analyzed and then take their recommended advice to make it potable.
There are various water filtration systems and products you can buy to help you with this task.
Selecting the right one depends on the state of your existing water and what microbes or metals are in it. Note that there are occasions when tap water contains higher-than-approved levels of harmful contaminants including metals, lead or salt, where your only recourse is to install a reverse osmosis system. These have become much more affordable and easier to install than they used to be. And it remains the best way to ensure safe water in some areas.