On Tue, 2 Nov 2004 14:00:39 -0000, "in2minds" wrote:

I will be moving various bits of soil piping around and have drawn a
blank on fall rates. From a look, old cast iron pipes look to have a
generally steeper fall than modern (smooth) plastic piping [which
makes sense].

I looked this up the other day and found reference to it being from 1:40
to 1:80

LJ


Thats is, if its too steep the water runs away, and the solids have no
water to travel with.

1 in 0 (vertical) is also allowed.

Rick