Sanitary Drainage Slopes Home › Forums › Public Forums › Drainage & Sewerage › Sanitary Drainage Slopes This topic has 1 reply, 2 voices, and was last updated 24 years, 3 months ago by Guest. Viewing 1 reply thread Author Posts 8 Sep 2000 at 3:43 am #278663 Anonymous Can anyone tell me how to convert slopes ie. 1/8 per ft=1/100, or 1/200=.5%. How do I convert this to percentage of slope? 8 Sep 2000 at 5:29 am #298992 GuestParticipant divide the fall by the distance. Author Posts Viewing 1 reply thread You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In