drain pipe size (diameter) for sanitary sewer

[et1883]

Interested in what size drainage pipes you all have for disposal of waste water, cooling water, etc.    Our drains are slow and we're wondering if we need to repipe to the street to have faster flow rate.   Welcome ideas.

[Sudzie]

Ours is a 4" SWD that runs 106' to the 28" main line with less than 1/4" pitch, "flat pipe". 600' to the north is one of our Carwashes that is also 4"SWD and that runs 397' to the main line with plus 1/4" pitch, "normal".  The carwash has peek flow rates of 95 GPM and there is no problem.  I doubt a distillery would have higher flow rates than that.  You may have a valley in your pipe (had that problem at our campground) that is causing a problem or sediment infiltrated the pipe due to a bad joint or cracked pipe.  Also I've seen a nest in the vent stack that impeded flows.   You may want to run a camera (with trace capabilities) down the line (couple $100) before you go too far. Hope this helps, -Dave

[et1883]

Thanks, Sudzie, we're scheduled to have someone in next week to scope it out with a camera to see what's up.  Good news about the 4" sizing!   We'll have a look at the vent stack too - it's a 20 year old building, so there could certainly be something in the stack!