Water Treatment and Wastewater Treatment are complex fields. Have you ever met someone that told you, he was fully confident to know everything about them? Well spoiler: that person lied 😀

But don’t worry, by patiently compiling (and never stopping!) all the questions I hear left and right, then looking for the best experts to answer them, I’ll build a definitive Water Industry cheat sheet for you right here.

Check it out ⬇️

Table of contents

1. About How Long have Wastewater Treatment Plants been in Existence?

The timelines of Water and Wastewater Management started around the same milestones, with the first large civilizations.

Around 3’500 BC, the first evidence is found of Water & Wastewater Management in the Mesopotamian Empire.

The Romans would then be the first to provide a full-circle integrated water cycle management.

And then… nothing!

With the collapse of the Roman Empire, everything that the Mesopotamians, the Indus, the Greeks, or the Romans had brought to human wellbeing kind of vanished.

Water would recover gradually. But for wastewater… the dark age would last over a millennial!

Dive into the depth of that story here to answer this simple question: how long do Wastewater Treatment Plants exist?

2. Who are the most influential people in the Water Industry?

This exercise is for sure very subjective, yet here’s my attempt:

5️ The Man who defied a US President
4️ The Water Detective that triggered an Industry Revolution
3️ The Man that triggered desalination – and got a dismal reward
2️ The Man that made Drinking Water “Pure and Wholesome.”
1️ The Technology, that’s somehow in my garden

To clarify my choices (a little), I also give you the list of people that were close to making it towards the end of this deep dive!

3. What is a Membrane Bioreactor?

It is the most rapidly growing wastewater treatment technology and has the power to turn a secondary treatment into an almost quaternary one.

Yet, 25 years ago, early pioneers were seen as slightly mad to believe, Membrane Bioreactors could become a thing!

At the time, membranes already had difficulties establishing themselves in clean water applications, so you can imagine that in wastewater, it was even worse…

What’s the secret of MBRs? We’ve made a thorough tour of the question (… and if there’s something missing, please reach out!)

Dive into the depth of that story here: What are Membrane Bioreactors?

4. What is Membrane Filtration?

As we’ve just seen, membrane treatments grew in 30 years to a dominant water treatment technology (almost from scratch). Yet, do you know everything about them?

I strived to put all the key knowledge about membrane filtration in a single place so that you’ll know the ins and outs of microfiltration, ultrafiltration, nanofiltration, reverse osmosis, and all their friends!

5. What is Ozone Water Treatment?

They may well be around for 120 years, but ozone plants are still a riddle to many.

Killer Gas? Killer Song? We investigate all of this in this ozone water treatment deep dive.

In short, ozone is tri-oxygen, an unstable form of oxygen that happens to be one of the most powerful oxidants on earth.

You can produce it by breaking dioxygen through UV radiation or electrical shocks.

… and once introduced into water, it may disinfect, purify, and remove specific pollutants (and much more).

So, did you know:

🍏 … that the “Ozone Layer” is almost a fraud?
🍏 … that the guy that discovered Ozone actually did not notice?
🍏 … that 19th-century hipsters saw the gas as a source of well-being?
🍏 … that the First World War almost killed ozone treatments?
🍏 … that it took the discovery of Four Horsemen to revive the ozone hype in the 1970s?
🍏 … that one of the major improvements in ozone generation resulted from another lab accident?
🍏 … that history was made both in the South-West of Germany and in LA?
🍏 … And that you can find ozone quite easily around you if you’d like to experience it first-hand?

No? Then you’ll love the video summary you’ll find here.

6. What is Singapore’s Secret to Nail Water Treatment?

Water is integral to Singapore’s success, and it is not a coincidence. Since the country took its political independence from Malaysia, it conscientiously built its water independence as well!

This water management marvel will be over in 2060 when Singapore cuts the last cord that still ties it to Malaysia, and it involves water reuse, the most advanced water treatments, and gigantic water infrastructure.

How does that work in detail? You’ll find out in this deep dive!

7. What is water treatment, and why is it necessary?

Water treatment is essential in making sure that we can use water safely and effectively. It’s not just about ensuring there are no chemicals or contaminants present but also making sure that the pH level of the water is ideal for our needs.

From industrial process water to potable drinking water, it’s important to make sure that proper methods are put in place to ensure safe and clean water for all our needs.

Depending on the source of the water, various processes may need to be implemented, such as filtration, clarification, sedimentation, sterilization, disinfection, or more advanced technologies (if you want to know more about those, you may want to subscribe to my podcast!).

All these measures are key to preventing any negative health impacts from using poor-quality water. It’s easy to take safe drinking water for granted, but without proper treatment processes, this wouldn’t be possible!

Oh, and in case you really took it for granted, did you know that 2.2 billion people on earth have no access to safe drinking water?

While we’re at it, what is wastewater treatment, and is it really needed?

Wastewater treatment is the process through which water is cleaned before being discharged to make sure it does not pollute the environment. Sometimes it gets reused, even though not enough!

Wastewater is generated whenever water is used. This wastewater can contain pollutants such as oil, grease, detergents, suspended solids, heavy metals, bacteria, viruses, and other pollutants.

Treating it is important because it prevents these pollutants from entering the environment and contaminating our water sources. Wastewater treatment also makes sure that water can be reused in some way, such as for irrigation or industrial processes. If untreated wastewater gets into rivers, lakes, or even oceans, it can cause water pollution and harm ecosystems. And before you ask, yes, we still don’t treat 44% of the wastewater on earth…

Wastewater treatment is usually done in several stages, starting with the removal of large solid particles such as sand, rocks, and wood. This is followed by biological treatment processes that use bacteria to break down organic matter, such as fats, oils, and grease. Water then gets clarified and sometimes further treated (to remove micropollutant or reuse it).

8. What are the 10 most common ways to treat water?

According to an informal survey, the most common ones shall be:

  • Coagulation and Flocculation (essentially a pre-treatment)
  • Filtration (which might be a pre-treatment or a polishing step, using sand or compact solutions)
  • Softening (now we’re really talking of a treatment in-house, not a “cleaning” of the water)
  • Ion Exchange (this is a polishing step or a key component in an industrial water treatment process)
  • Distillation (very effective to remove everything from water, yet not really used outside of industrial purposes)
  • Reverse Osmosis (the go-to for desalination and reuse applications)
  • UV Disinfection (the most cost-attractive disinfection tool – very common in drinking water applications)
  • Ozone treatment (not much to say, you just have to scroll a bit up on this page to learn more!)
  • Chlorination (arguably the major health improvement we’ve seen at the turn of the 20st century)
  • Activated Carbon Filtration (a broad catching solution that might be expensive, but that’s pretty effective)

9. What are the main contaminants that need to be removed from water during treatment?

10. What principal contaminants need to be removed from wastewater in a treatment process?

11. What’s the weird history of New York’s Drinking Water?

12. What are the 5 most common types of water treatment plants?

13. How is Filtration inspired by nature?

How does it work?

14. What is the most common water disinfection process?

How does it work?


16. What is the difference between primary, secondary and tertiary wastewater treatment?

17. How can ultraviolet make us tan AND disinfect water?

18. How much of the World’s drinking water is produced through desalination today?

19. What are the potential health risks of improper wastewater treatment?

20. How does pH affect water treatment?

21. Glueing it out: what’s the role of coagulation and flocculation?

How does it work?

22. What are the most surprising regulations governing water treatment in the World?

23. Why do we even need treatments to ensure safe drinking water?

24. What is the role of biological processes in wastewater treatment?

25. What are Denmark’s Little Water Secrets (You should probably steal)

Denmark is the country with the most expensive drinking water. And also – in quite related news – the country with the most sustainable water management there is!

Now, that has not always been the case; excellence is never a given. It did not happen overnight, but there’s a lot many other countries may want to steal in this approach, let’s wrap it up in just 2 minutes ⬇️

26. Can wastewater treatment be used to generate renewable energy?

27. Can wastewater be treated and used for agricultural irrigation?

28. What are the 3 most innovative technologies currently developed to improve wastewater treatment?

29. How can wastewater treatment help to reduce greenhouse gas emissions?

30. Can wastewater treatment be integrated with other industrial processes to improve sustainability?

31. What are the potential long-term effects of the use of water treatment chemicals?

32. How does water scarcity affect communities and industries around the world?

33. How to get rid of PFAS in Water?

PFAS can be difficult to remove from water due to their chemical properties.

Treatment options for removing PFAS from water include granular activated carbon filtration, reverse osmosis, and advanced oxidation processes (AOPs). Granular activated carbon filtration is a common method for removing PFAS from water, but it can be expensive and may not be effective for removing all PFAS. Reverse osmosis can also be used to remove PFAS, but it is a more complex and expensive process. AOPs, which use chemical reactions to break down PFAS molecules, is a newer treatment technology that shows promise for removing PFAS from water.

But the most effective approach for removing PFAS from water will depend on the specific characteristics of the contamination, the water source and what levels you effectively want to reach at the output.

42. Is the future to build Wastewater Treatment Plants underground?

Since the early 1900s, Stockholm has used a unique method of treating wastewater: instead of a conventional #WastewaterTreatmentPlant, they use… a mountain!

Wastewater from all over the town is collected and treated to the highest standards in Henriksdal and beneath the Hammarbybacken ski slope. And it isn’t over yet!

Stockholm Vatten SFA project will increase the plant’s capacity, improve its treatment performance, and collect the remaining wastewater that is currently flowing through Bromma to treat the entire city’s sewage in one location.

Have you ever seen Dr. No’s cave in a James Bond film? Imagine a modern wastewater treatment plant in it, and you’ll have a good idea of what Henriksdal is all about!