I was going to title this thread “sanitation engineers: flow rates and drop manholes”
But you gotta admit it–the title I used is catchier, and might get more responses. So I decided to be rude. Sorry…I won’t do it again, I promise)
Now my technical questions:
How do the solids move in sewage pipes? Some pipes are filled with liquid, and the solids float along.But some pipes are totally dry (like the connection to my house) When I flush the toilet, why doesn’t the small quantity of water flow faster than the solids, which I would expect to get “left behind” and clog the pipe.
And how do drop manholes work? The flow drops straight down, at a 90 degree angle. I understand how this slows down the liquid flow, and allows for lower gradients in the pipes. But how do the solids re-enter the flow of water, after falling straight down and presumably dumping a splotch of gooey mess on the concrete below?
Also–why do manholes of sanitary sewers have a concave channel in the floor, and storm sewers don’t?