For centuries, philosophers have a civilized society as one having a written language. It's great to have someone who can record the great things the current king has done, but the real basis of civilization is plumbing. The number of people who can live in a small area depends on how much water is available, which is why all the great ancient cities were built by a river. The real problem of cramming a lot of people into a small area is not providing water, it's dealing with sewage. There is a finite and relatively small number of people who can live on an acre of land without a working sewage system. True civilization arises when they develop the technology to take the sewage back to the river, preferably down stream of where the drinking water is dipped out.
My city, like all American towns with a reasonable tax base has a sewer system that always has some part being dug up and rebuilt. Since the 1960s, our biggest maintenance issue was not broken pipes. It was kitchen grease. I could roll a 10 penny nail in cornmeal, deep fry it, and someone will smell the hot grease and ask if they can eat it. It's a Louisiana thing. The real problem was restaurants, which could need to dispose of fifty to a hundred gallons of cooking oil a month. It went down the drain, where it congealed in the cool ground. We don't have sewer pipes large enough to form fatbergs, so it just reduces the flow rate to a trickle.
The solution was to make it illegal to pour kitchen grease and other byproducts down the drain. Besides that, building codes require restaurants to have a sump in their sanitary drains which lets grease float on top and water run out the bottom. Every so often, it has to be skimmed.
It's just another set of government regulations which make it harder for a business to make profits, but it's much better than coming home to find two inches of sewage has backed up into your bathtub.
