Throughout this wastewater series we have discussed the user interface of the treatment process. The modern paradigm involves a separation of the user (that’s us) from the waste management, resulting in poor consumer/user behaviour and inefficient systems. By now you should be clear on my position towards this. If not, let me clarify: I think it’s stupid. To find out why, check out my previous posts here and here. The key takeaway is that user accountability for what gets flushed is critical to create and ensure an efficient, system-wide treatment process.
The idea of treating wastewater is a relatively recent revelation. The Romans, whilst inventing running water, simply removed it through a sewer system and released into rivers. This is so they didn’t have to look at it, smell it, physically remove it, whatever. This was more or less the pinnacle of wastewater management (save for some minor adjustments, like the cesspool) until the 19th century, where city populations grew so dense that outbreaks of cholera and other nasties demanded change. More rigorous regulatory restrictions were a reactive response, pushing us towards the bigger is better, centralised treatment regime we see today. Unfortunately, many people are still suffering the consequences of poor water management practices today (check this piece out for some heavy truth bombs)
So, the historical trend for wastewater management is:
- Remove then dump
- Remove, treat then dump
So what’s step 4? What does the future hold?
I’m glad you asked.
Currently, the treatment trajectory is tracking towards bigger, more expensive treatment plants of higher capacity and quality. I know, I’ve said it a million* times. But looking at the conveniently structured, easy-to-read list above (you’re welcome), is it not more logical to make Step 4: Remove, treat, re-use? Or even better, just Treat, Re-use?
The water corp in Perth is making strides in this area, with the acceleration of their groundwater replenishment project. While still using a large, centralised treatment plant, it employs a life-cycle thinking approach, and employs ecological engineering principles for a resilient city: using the output of one process as the input of another to diversify drinking water supplies.
I think this is good step forward, but still ascribes to an unsustainable management model. I think a treat, re-use step 4 is the way of the future. This would essentially involve in situ treatment of wastewater, removing or at least reducing the need for and cost of transporting it across the city to be treated and dumped/recharged/whatever.
All of our homes, schools, businesses, and so on, have a hot water system on premises. It would not make sense to have a large, centralised water heating facility that distributes to properties. This would be inefficient and expensive. So why can’t we have a water treatment facility at homes as well?
Check out my vlog below for some tantalising, tangential talk.
Our lives are defined by convenience. Forget something from the shops? No worries, you can have groceries delivered online. Feeling lonely? No worries, just jump on one of the many social media platforms that bring social interaction to your living room at the click of a button: you don’t even have to get out of bed if you don’t want to. I’m not saying I don’t enjoy these luxuries (soz about the double neg there), but I do think there’s something to be learnt here.
Imagine (all you city slickers) if you had to physically remove all your household rubbish, ie there was no collection service. I’d be willing to bet you’d start creating less rubbish (either consciously or subconsciously) to reduce the frequency of the trips you had to make. In a similar vein, if you had a domestic sized wastewater treatment facility at your house (similar to having a hot water system) and you had to call the plumber for maintenance, would you start being vigilant about what you flush? Would you put oils and wet ones in the bin rather than clogging your own treatment plant?
The great thing about a system like this is that we could re-use our waste in situ, initially for watering the garden or toilet water, or even in HVAC systems. As the technology develops over the next century, we can (i think) expect (probably) to be able to screen for the constituents of concern (like hormones, hopefully microplastics won’t be an issue by then as countries are already calling for their ban in commercial products!) that currently scoot on through the sieves, reverse osmosis, and ultraviolet stages of the treatment process. We could then confidently use this water showers, drinking, washing dishes, filling swimming pools, the sky’s the limit!
In-situ treatment encourages greater user interaction and accountability for what goes down the sink – a repair person (let’s call them a plumber) would have to be called more frequently for those who insist on flushing and forgetting, leading to higher maintenance costs. BUT, people would have the opportunity to greatly reduce costs by thoughtful wastewater practices, as well as re-using their own water, cutting water bills like crazy! If this were integrated with a passive heating/cooling system, electricity bills could also be slashed! Sounds HOT right? Radi-cool even?
But what about the solids? The stuff that gets filtered out?
Well, this could either be stored in its individual components (as its removed from the wastewater) and then re-used for other products, or it could simply be lumped together and collected with your weekly rubbish collection, or, you know, by pneumatic tube (see meme below, loving created just for you, avid reader) because we all know we’ll be using those for everything in the future… Or maybe you have an idea for this? Like composting, or use in vertical/rooftop gardens? Let me know in the comments!
In conclusion, I think separating people from their wastewater, whilst done with the best intentions 2000+ years ago (thanks a lot Romans), has inevitably led to our nonchalance and laziness towards its treatment. There are great opportunities for reduced spending on infrastructure, as well as more efficient, user-friendly, user-interactive systems by introducing household treatment. Maybe we’ll finally be allowed to have greywater systems in WA. Wouldn’t that be nice?
Well done on making to the end of another wastewater (not timewaster) entry. Come back next week for the final instalment!
See ya later alligator. Don’t forget your toilet paper, and only flush it if it is indeed toilet paper and not wet ones. You shouldn’t still need reminders. You’re better than this.
PS. World’s longest sign-off ever. Kind of like when you say goodbye to someone and then realise you’re going the same way and have to keep talking for a bit and say goodbye again in like 3 minutes. Sorry. Bye. Again.
*not actually a million times. Much less than that, but still a lot.
Useful Links and References for your convenience
Check out this paper for more on Ecological Engineering principles
The almighty Encyclopedia Britannica has a great resource on Wastewater history, treatment, and constituents. Check it out here.
Here’s a little more on the history of wastewater treatment
The Water corp explains their groundwater replenishment scheme here.
Memes created at memegenerator.net. Would recommend/10
Images once again illustrated by yours truly (in the vlog this time though… Plot twist amirite?). If you’re wondering, I do take requests… 1 million dollars. Muhuhuhahahahahaha.