It’s a big week at the Tech School with our Term 3 Girls and Boys in STEM Program running - this time we’re looking at Waste Water which is far less stinky than you think it would be. I’m writing this on Thursday night because tomorrow I’ll be helping to judge our students' solutions to problems like stopping fat bergs and removing PFAS from our water system. We’re doing all this alongside our generous industry partners Central Highlands Water.
The last few days have been fascinating because I simply didn’t know what happened at the waste water treatment plant. I think most of us have taken the fact that we get clean water in and dirty water out of our homes for granted. Unless there is a major problem, of which I’d had a few, we really don’t need to understand much more about it. Going into this program so naive was a great position to be in because it meant that I was impressed by everything.
As I mentioned above - sewage doesn’t smell as bad as you think. One poo a day is the recommended dose then the rest of a household's waste water from kitchen sinks, showers and washing machines. As long as sewage keeps moving, it shouldn’t be offensive. Keeping things flowing is the trick and we visited a pumping station to see how they get waste from the bottom of a hill to the top. Once the waste hits the waste treatment plant it goes through a series of processes to remove things that shouldn’t be there (wet wipes, tampons, nappies etc) then its flow is slowed right down so they can remove fats and oils off the top while collecting hard solids along the bottom.
The water then enters a series of ponds that are basically a massive anaerobic digestor where bacteria is tightly controlled to break down the organic matter. This is why it is so important to only flush the three P’s (poo, pee and paper) because anything not organic isn’t going to break down. The final stage is massive lagoons where the water rests before being let out back into the environment - sometimes cleaner than it was in the first place.
This whole process pretty much includes every type of science and engineering role you can think of. It uses 2000 year old technology (archimedes screw) alongside a cutting edge, multi-million dollar centrifuge. For a city of 185,000 people, Central Highlands Water employs just over 210 people to run the show. It's pretty incredible considering that they average around 20 million litres of waste water per day. I especially loved how passionate all the staff we spoke to were.
I love surprises and I can honestly say that I was surprised at how interesting learning about waste water management was. Tomorrow our students will be presenting their solutions to our industry experts and it is wonderful to see how much more appreciation and knowledge they have about their local water system. Each and every one of the students (and me) will be going back to their homes and educating their families about what should and shouldn’t go down the drain.
This is yet another important industry that I had no idea about. When everything is going fine, we don’t even think about what happens to water when it leaves our house, but when shit hits the fan, we expect an immediate response - CHW are quick - I know for a fact after having them on speed dial for our various shit rentals, I even meet one of my heroes who saved us at our current property.
I think every kid should go for a tour around their local waste water treatment plant - you can’t unsee a fatberg and prevention is always better than a cure. For those of you who have never seen a fatberg before, please, google it. They're awful, foul, man-made beasts. You’ll never flush anything other than the three P’s down the drain again!
