Winter Prep (Part Two) Water Out - Waste Water

I’m not an expert – just experienced

Here is a sewer hose that will drain completely

photo from twopennytravels.com 

Here is a sewer hose that will

not drain completely and will freeze

in the winter.* photo from RVTravel.com

Okay, so I hope that in Part One I convinced you that you want a site with a sewer hook up.  Now, about that hook up, you want to keep the dump valve closed until you have at least three-quarters of a tank so that you get a clean dump.  You need the force of moving liquid to move the solids.  That's as nice a way of saying as I could think of.  .  It is critical that the sewer hose has a constant decline to the sewer.  If it does not have enough of a drop, waste will collect and freeze in the hose.  Many people (myself included) run the hose into or through a PVC pipe to make sure that there is no ‘sag’ in the line.  Other folks use a section of rain gutter as a bridge that holds the hose.  Either of these systems will work.

You may wish to put insulation around the waste hose to give the fluid more time to drain before the freezing temps cause a problem.  I have seen people add heat tape to the drain hose also.  I do NOT recommend that.  Heat tape works fine on water lines that have water in them.  Full lines are less likely to over heat.  An empty sewer line may melt or scorch from the heat of a tape.  There MAY be tapes made for this purpose, however I’ve never seen them. 

Frankly, if the sewer line has the proper decline it should run fine except in the very, very, very, coldest weather – when you are not going to go out to empty your tanks anyway.

One last thought on sewer lines.  If you are really concerned that they may freeze, add some RV/Marine Antifreeze down the stool.  Make sure it is RV/Marine Antifreeze and not engine antifreeze.  You can find it a almost any auto parts or home store like Home Depot, Menards, Lowes or even your local hardware or grocery store may carry it if you are in an area where it is demand.

*About the hose that will not drain properly.  To be fair, that is what the person was trying to accomplish.  By forming this "P-Trap" in the line they could leave their dump valve open all the time without sewer gas entering their RV.  You could certainly do this where you need not worry about freezing temperatures.  However, if it freezes, it will block the flow and possible rupture the hose.

(Next topic;  Water In – Fresh Water)