I’m a water engineer with a PhD, so not a tech nerd but definitely a nerd :) I came here mostly because I find the Reddit app annoying and the app I was using came here.

The Romans used lead as a sweetener…

I don’t know the details about alum production (assuming that is what you are referring to), but there are many alternative coagulants available now. Sure the supply logistics would be incredibly challenging and many people would have to boil their water or use point-of-use filters, but this take is pretty doomer in my opinion. Most plants use alum because it’s cheap and easy, not because it’s their only option.

Math using janky excel spreadsheets, tell drafters what we want drawings to look like, but mostly a lot of reading and writing. The secret to engineering (at least in my area) is that communication skills are just as important as technical understanding.