We all know that baths take a ton of water, I mean you literally have to fill up a tub, and even the smallest one is pretty big. Plus, you don’t need baths, plenty of people only have a shower in their house and they’re fine, actually, I’d wager only a minority of people in the world, mostly Westerners, even have access to a personal bathtub.
So what do you think about taking baths (in the Western style where you drain the water after each user, not talking about public baths or hot tubs)? Do you think it’s fine occasionally in order to relax? Or do you think the massive water usage is never justified? Going further, do you think new houses should be built without bathtubs, only showers?
There’s a whole paper on this which an environmental engineer friend of mine sent me:
McDermott, R. , Strong, A. and Griffiths, P. (2019) Solid Transfer in Low Flow Sewers, the Distance Travelled So Far Is Not Enough. Journal of Environmental Protection, 10, 164-207. doi: 10.4236/jep.2019.102011.
https://www.scirp.org/journal/paperinformation.aspx?paperid=90286
Thanks! This is great and comes with a whole pile of cited material.
tldr; Our pipes need water to work. Low flows and intermittent flows can be a contributor to blockages, but are not in the top causes. What about baths (pretending this is all on topic)? If you take a bath, the best way to drain your tub to maintain your home’s pipes would be to let some water slowly trickle through to wet down anything that has dried in the pipes, then open the drain all the way to rinse them clean.
Now a longer summary of relevant points. It is a meta study. The main flaw in the study is that they are aggregating data from small pipes like those in your home with the large pipes that are managed by your sewer service. In doing that they conflate the ability to move poop through your toilet with preventing sewage backups that would flood a street. Flaws and all, it has tons of merit. Here is what they showed as the most common contributing causes of sewer blockages with how many authors cite the cause: 7 authors - tree roots; 5 authors - flushing non-flushables; 4 authors - depth of pipe (because of potential collapse and tree root intrusion), fats oils and grease, small diameter, quality of construction; 3 authors - flat gradients, joint material/type (because of breakages), junctions (shape of flow), ground conditions (ground movement breaks pipes), intermittent flow, solid deposition (poop, tp, and garbage settling out, it’s bad if they’re allowed to dry in place here’s where low flow and intermittent flow could combine to cause issues); 2 authors - age of sewer, self-cleansing velocity (having frequent enough high volume flows to wash the pipe).
Nice tldr amd analysis! Yeah, modern piping wouldn’t require that much flow.