Water is essential for all life, it aids in dissolving and transporting nutrients inside our bodies. Our bodies are even made up of about 60% water. We should be consuming water everyday but do you ever think about where that water is coming from and the processes it goes through that makes it safe for us to drink?
Typically water treatment facilities treat and filter the water that is supplied to the sinks we use in our homes, offices, restaurants, etc. These facilities process water from sources like groundwater, rivers, lakes or water stored in wells, reservoirs and other storage tanks.
What happens at a Water Treatment Facility?
Treatment facilities remove impurities from the water:
- Heavy Metals (Copper + Lead)
- Chemical Pollutants
Once water enters a filtration facility it goes through many levels of purification before it comes out of our taps:
- Coagulation and flocculation: This is the first step, positively charged chemicals are added to the water so they can bond with the negatively charged chemicals are create larger particles called floc.
- Sedimentation: The floc created in the first step settle at the bottom because they are heavier and then can be removed easily.
- Filtration: After removing the floc, the rest of the water is put through various filters (sand, gravel, charcoal) to remove the smaller dissolved particles like dust, bacteria/viruses and chemicals.
- Disinfection: After the water is filtered, a disinfectant like chlorine is added to remove any remaining viruses and bacteria before it is pumped to our taps.
What happens next: Is it safe to drink tap water?
In most western countries, consuming tap water is usually safe. But this largely depends on where you live, it can often still contain trace contaminants. The EPA sets country-wide tap water standards but each state is able to regulate their own water facilities as long as they meet the EPA's general requirements.
If you are interested in learning more about the water supplied to your house, you can contact your local facility to learn more about their process. You can also check the Environmental Working Groups tap water database where you can view your tap water's safety by entering your zip code.
At-home water purification
If you are worried about tap water, there are several at-home water purification systems that allow you to further filter your drinking water. You probably already have something like this at home but here are the most common in-home purification systems:
Water filter pitcher / countertop filtration systems: These are a super easy option to further filter your tap water. Either you have a pitcher or tank that you can fill with tap water that runs it through a small filter. They are inexpensive but filters need to be replaced often and usually filters pretty slowly. A great option if you do not have a refrigerator filter.
Refrigerator filters: These are filtration systems built right into your fridge, and they typically come with most refrigerators. They even often also include an ice maker. These don't require you to have to continually fill up a tank or pitcher but you will have to replace your filter fairly often.
Faucet-mounted filters: These are attached right onto your faucet and allow you to switch between filtered and regular tap water. They are also typically pretty cheap but do not work with every type of faucet.
Built-in faucet filter: These filters require installation, typically under the sink, and they purify the water coming right out of your faucet. Like the mounted filters, they allow you to switch between filtered and tap water but they are much more costly and require installation.
Whole-house filtration systems: These systems treat all water in the house, not just your drinking water. This is often very beneficial for homes or buildings that struggle with hard water. These can be very expensive, require installation and often extra plumbing modifications and even need professional maintenance.
Figuring out what type of at-home water filtration system is right for you largely depends on where you live, what you can afford and personal preference. If you have health conditions, talk to your doctor about which type of water is best for you.
How do these systems filter your water?
There are 3 main ways that these systems filter water.
- Activated carbon: Carbon systems filter water by sending the water through a filter of tiny granules of carbon which absorb particles like heavy metals. This is best at removing additives like chlorine that can give water an unpleasant taste and odor. This filter process is used in pitcher/countertop filters, refrigerators and some faucet-mounted filters.
- Ion exchange unit: This system works by removing dissolved ionic contaminants, it basically replaces the unwanted compounds for more desirable ones. A great example of these are water softeners, these remove elements that make water "hard" and replace it with sodium. This usually is common with whole house water treatments.
- Reverse osmosis unit: This works by pumping water across a barrier/membrane that leaves the unwanted particles behind. Reverse osmosis units are not typically recommended because they can have negative health and environmental impacts. This is typically used in built in faucet filters and some countertop tank filters.
What about distilled water?
Distilled water is basically just a type of purified water. It is filtered by boiling and then steam condensed, this leaves you with almost completely pure water. It is safe to drink but its not really beneficial, it does not contain any extra minerals and will probably taste pretty bland.
There is no universal answer to which water you should drink, if it is safe for you to drink your tap water and you like it then go for it! But, it is likely that you have some type of filtration system at your house.