[VAC] Re: Tapping into an existing septic system

[Jim Dunmyer <jdunmyer@xxxxxxxxxxx>]

Scott,
 Your scheme would work, but sewage pumps can be problematic. I'd try
tapping the line going into the septic tank (probably a 4" size),
installing a 'Y' fitting, then a straight run to your personal "dump
station". You should have about 1/4" to 1/2" of fall every ten feet of
pipe. As Gerald suggested, you might want to consider a 'P' trap to
prevent fumes from escaping, and you might need a vent stack. The latter
can probably be dispensed with because your B.W. and G.W. tanks are
vented through the roof of your trailer. 

Obviously, you'll operate your trailer dump valves just as if you were
at a regular campground, holding the B.W. tank until it's 1/2 full or so
before dumping, then following it with a few gallons from the G.W. tank.
Try to avoid putting TOO much water into the system at once because that
tends to cause problems with the septic tank and leach field.

If you go with the sump plan, use a regular sewage lift pump, not a
regular sump pump. They're meant to handle sewage and will do a good
job. The only real problem is that they're obviously not as reliable
over the long term as plain ol' gravity. You might consult with a local
septic tank installer on the details.

                                          <<Jim>>