Digging Deep Into Groundwater Treatment


Welcome back to Aquastructure, our year-long blog series where we help you, loyal water user, become a real-life expert on all things H2O. We’re going behind the scenes of Aqua’s daily operations to break down all the complicated systems that work together to bring you clean, refreshing water each and every day.

Last month, we learned all about surface water and the treatment process that goes into making water from lakes, rivers and reservoirs clean and crisp. This month, we’ll tackle groundwater and learn a bit about how that water becomes something we actually can put into our bodies.

We turned to Alissa Vanim, manager of environmental compliance at Aqua New Jersey and Joe Mingle, director of operations at Aqua New Jersey, to get the 411 on groundwater treatment.

SO WHAT MAKES GROUNDWATER SPECIAL?

Let’s start with the most obvious fact: groundwater comes from—drum roll, please—the ground. Deep within the earth, there are underground wells that collect buckets beyond buckets of water from aquifers, which are layers of rock and soil that transmit water. Those aquifers contain water from a mix of natural sources, such as precipitation (like rain or snow) and nearby rivers and streams.

But that well water isn’t as drinkable as we’d like—it’s been hanging out in the dark hundreds of feet below the ground, after all.  

groundwater

OKAY, BUT HOW DOES THE GROUNDWATER LEAVE THE GROUND?

After a while, those wells fill up, and it’s time for all that groundwater to see the light of day. So off it goes to a treatment plant, where the water undergoes various treatment processes depending on its quality. This may include a bit of the ion-exchange process. The ion-exchange process sounds super complicated, but it’s really just a mix of positively and negatively charged ions doing some black magic to remove contaminants such as nitrate, fluoride, sulfate and arsenic.

IS THAT ALL?

Of course not—that’d be too easy. There are also activated-carbon contactors that absorb other chemicals that don’t belong in our drinking water. This improves the taste of the water and removes odors as well.

Sometimes nuisance metals, like iron or manganese, seep into the water, so that’s where sequestration comes in. This process makes sure the water isn’t discolored or metallic.

Lastly, there’s aeration, which raises the pH levels and removes CO2 gases from the groundwater. All in all, this pre-treatment process is just a necessary step we have to take to remove a ton of harmful pollutants from our water. 

IS THE NEXT STOP CHLORINATION?

Back in the day, waterborne diseases wreaked havoc on society. But thanks to chlorination, all those harmful bacteria and viruses (think: salmonella, E-Coli, Coliform, Legionella and fecal coliform) get destroyed so we can go on living happy, healthy, hydrated lives.

groundwater

Once all that water has been chlorinated, it moves on to post-treatment. Here, green sand filters pull out any additional iron manganese and hydrogen sulfide to achieve optimal water quality. Finally, post-treatment chlorination is added as the last process before delivery.

CAN I GET THE WATER NOW?

Now that the water is clean, it’s time to send it off to you, the water customers of the world. If the water is not immediately needed, it is transported into large, elevated storage tanks. From there, all that safe, drinkable water gets distributed to you via underground pipes so that you can drink it, cook with it, wash with it or flush it away to your heart’s desire.

Ta-da! That’s all for groundwater treatment, folks. Join us next month, where we’ll provide all of the (dirty) details on wastewater.