Toilets and Plumbing/Night soil

[RussMaster]

I'm surprised this isn't in the game already. I think adding toilets and a need for toilets would be a fitting addition for the game. If you don't have toilets, colonists would try to go outside to use relive themselves (or maybe even just do it in base if they have a trait). This makes a massive drop in moral for everyone if left unattended, and an even bigger drop for whoever has to clean it off the floor. It can also lead to disease if left alone, or near food.

To remedy this, the use of Outhouses, and full on proper toilets can mitigate the chances of your colonists reliving themselves out in the open (although there may be some who are slow to want to use the toilet [IE San Francisco]). That would be a good option to arrest and detain colonists to reinforce a proper bathroom policy, and something tells me not every tribal cares to use the toilet.

Of course, Proper Hygiene is important and should be noted. That's why I think adding Wash Basins, Sinks, and Showers would also be a good addition, as a way to improve mood, and slow the spread of disease.

Now, all of this begs the question of what do we do with the waste we collect. One option would be a temporary solution of just dumping it into a pit in the world, similar to pollution, except not radioactive, just disgusting. A second option would be dumping it in a body of water (with different effects depending on if ocean, or river). Dumping it in the ocean would require a pipeline from a sceptic system to an ocean, but it would no longer be your problem. Dumping it in a river however would result in all water going downstream to be contaminated. This could piss off colonies downstream of you, as well as spread disease (This could also happen to you if your downstream of a colony with no hygiene).

The third option however is to refine the sewage, and turn it into fertilizer, increasing fertility for applied tiles. It will be applied to all crops within a growing zone, and is used to upgrade soil into rich soil, improving plant growth. This could be good for mega farms, and improve cash crop efficiency. You could even sell fertilizer straight to other tribes if you want to make some quick money.

You could also add these features to an agriculture update, leading to an entire rework of soil fertility, and a need for constant fertilizer, or nutrient replenishing crops and crop rotation. That's all a DLC for another day though.