Water supply facts and figures that will stop you right on your tracks! - Part 3
As we learned in the previous story, water is created deep within the Earth and arises to the surface through several of Earth’s phenomena. Water doesn’t only start off falling from the sky, but it goes around in a cycle, not starting or ending in one place, always being re-cycled.
If you think our water supply is this eternal, never-ending downpour of water, think again. The water we use on a daily basis is recycled. And that’s a good thing, there is so much of it!
Our city’s water supply gives us water, we use it, and it gets fed back into the system to be treated and out again for further use. And on it goes on a loop that keeps us all alive and (not too) well!
Whether you take it from the faucet or from a bottle, it’s the same liquid!
Nowadays, water used in our homes primarily comes from groundwater or surface-water (river, lake or reservoir) and is delivered by a public supplier. Towns and cities have what is called a public water-supply system.
A minority, particularly from rural areas, to this day get their water from a water well (groundwater).
Groundwater or surface-water is contained in huge reservoirs, rivers or lakes and is then accessed by building an intake to draw water that is subsequently sent to the water treatment plant before it reaches your home.
Water wells, one of the first systems to get water, still in use today.Do you know the name of your watershed?
Your local watershed is the primary source of water you and your community use. Very few people know about their watershed but as time goes by and water issues become ever more essential, knowing your local watershed will become as familiar as knowing the name of your town – your life depends on it.
“Raw” water from these reservoirs is not fit for human consumption and thus must be treated.
Surface water requires more treatment than groundwater because this last one is naturally filtered through the aquifers. Surface water will have leaves, branches, dead wildlife and other things picked up along the way.
The journey water makes through a water treatment plant is pretty remarkable
It is one of the greatest achievements of humankind to have learnt to treat water, make it potable and then distribute it to the population.
So how is water made potable? What goes into getting water from, say, a river and into our homes?
Local water supplies treat water in order to take out any dirt particles, organic matter and contaminants – the treatment process required by the Safe Drinking Water Act that all drinking water must go through before it is sent to your tap.
In the water treatment plant, water goes through at least five stages
As explained in a special PBS chapter (see reference at the end):
- Air is added to water, called aeration, which adds oxygen to water and at the same time allows other gases to escape.
- Water is then coagulated, made into large clumps, in order for it to settle at the bottom.
- Once in the bottom, sedimentation is the process that allows the clumps to settle so particles can be collected.
- Water then goes through several filters to be further cleaned.
- Finally, water is disinfected with several chemicals to kill bacteria and other germs.
Water already treated, made potable, is routinely tested to EPA standards (up to several times per day!) and then sent into a network of interconnected components all the way to your home. These pipes have different sizes, are made of different materials with diverse methods of construction and their age is different in every town and home.
Most of the water towers you might see in your community store water and act as secondary sources of water in case some days there is more demand than supply. Some of these towers can hold up to 1 million gallons of water!
Water treatment plant.Did you know? Water supply distribution systems in the US span almost one million miles
Once you use the water at home, be it, taking a shower, cooking, washing dishes, doing laundry, using the toilet or cleaning your swimming pool, it becomes wastewater (which is a terrible name – water is never a “waste”. It’s precious!).
Business and industries also release great amounts of wastewater, often, carrying with it toxic chemicals, machinery by-products, industrial substances, and other harmful fluids.
Wastewater can include many substances like human waste, food scraps, oil, soap, and chemicals (like the Clorox you use to disinfect your toilet bowl). All this goes “down the drain” and into another, parallel, network of pipes that leads to the wastewater facility.
Wastewater here is treated to remove some the substances so it can be returned back to the environment safely or to be reused for non-potable applications (like irrigating crops, parks, firefighting, etc.).
Sewage water can be recycled for human consumption. For example, California’s Orange County Water District has a plant that recycles used water and returns it into the drinking supply since 2008. With California seeing bad droughts year after year and its reservoirs at record lows, recycling water within a larger water supply system represents a model solution.
Sedimentation tank at a water treatment facility.The first country to pioneer such a feat is Namibia
Check this amazing article about: “Recycling sewage into drinking water is no big deal. They've been doing it in Namibia for 50 years”.
Water is thus, collected from the natural environment, treated to make it fit for human use and then distributed through cities and towns via the water supply system.
At the end, all it takes is a turn on our faucets for the vital, color-less liquid to come out
However, the long and winding path it takes until it hits your home can be a source of concern. In what shape is the overall network of pipes in your county? How old are the water mains in your town?
What is the material of the pipes in your home?
How does this impact the water you drink?
Our water supply system is an invaluable resource in our community. It allows us to have potable water on demand and it allows the economy and all human endeavors to run without a hitch.
However, the EPA standards to test city water are just that, standards. Our water supply and treatment systems do not completely clean our water. And add to that the elements picked up along the network of water pipes before the liquid gets to your home.
Clean out your water supply at home
Only a high-tech water filtration system will be enough to purify the water supply in your home. So that you and your family drink with no toxic substances.
How many contaminants are OK with you?
In the next part we'll dig deeper into what is in our water supply.
Part 4 - Contaminants in your water
U.S. Geological Survey, Water science FAQ, https://water.usgs.gov
PBS News Hour, Understanding your water, www.pbs.org
Environmental Protection Agency, Drinking water distribution systems, www.epa.ogv
Public Radio International, Recycling sewage into drinking water is no big deal, www.pri.org
CNN, From toilet to tap, www.cnn.com
