Sewer Dumping ProcedureThe following was written by Gary Brinck in response to a question in the RV Forum about the sewer dumping process.
It's really pretty simple, but sooner or later you will probably have an "Ooops!". The explanation below is long because I've tried to cover numerous related points, but the whole procedure is really quite simple and clean. My wife often does ours if I am busy with something else.
First off, though, try to have the black water tank at least half full before dumping, and preferably much more. And be as generous as you can afford to be when flushing the commode, to increase the percentage of water versus paper and solids. The reason for both of these is that a good outflow of water helps to wash the "other stuff" out of the tank and prevent clogs around the valve area.
Second, dump the black water tank first, then the gray water (sinks/shower etc.). This rinses out the last section of pipe and your sewer hose somewhat, getting rid of clingy paper.
Finally, use a toilet paper that dissolves readily, preferably a single ply, white unscented paper. Paper that is colored, printed or scented is made of a heavier, more fibrous paper and is generally harder to dissolve than plain white. Scotts single ply white is excellent and some others will likely offer their favorites too. The special RV toilet papers are not necessarily the best or even good - they often show up very poorly in tests.
There is a standard locking connector on the end of your RV's dump pipe. Make sure your sewer hose has a matching connector and that the rubber ring in the seat is OK. The connectors are inexpensive, so replace it if you get leakage even when it is seated. Also make sure the hose clamp is tight (one brand of connector screws into the hose coils and supposedly does not need a clamp, but...).
Most of us also have an elbow connector on the other end of the hose, which fits a variety of dump/sewer hook-ups. It will have a couple sizes of threads and a slip-in area as well, so it can be used most anywhere. They are available at RV dealers, Camping World, etc. You should also have a rubber "doughnut" to use with dump pipes that have no thread - many states or parks require their use.
So, slip the hose connector onto the RV's pipe and twist to lock it in place. DOUBLE CHECK that all the locking fingers have engaged all the way - you definitely do not want the hose to fall off with the first rush of water! Run the hose out through the opening in the bottom of the bay (if provided) or straight out and down if the drain pipe is not in a bay. Try to avoid sharp turns of kinks in that first couple feet, so the water can flow easily without backing up.
Place the other end of the hose in the dump station of site sewer opening and secure it into place somehow, because the rush of water may cause it to thrash about. If your hose connector can screw into threads, all is fine. If not, lay a stone or heavy boards over it to help hold it down - you will often see these lying near by, left there by the last person who dumped. If nothing is available, place a foot on the end to keep it in place (may need a helper here).
After making sure both ends (and any middle connectors as well) are secure, pull the handle on the black tank dump valve and wait till it finishes, Black is a big pipe and doesn't take long. Then close the black valve and open the gray valve to dump and rinse. Gray uses a small pipe and may take some time. When finished, close the gray valve and raise/jiggle the hose a bit to see if water remains in the sewer hose (it often does). Work the hose to drain as much water as possible and then carefully disconnect the RV end, keeping the now-open end as high as possible in case water remains in the hose. Raise it high to force any remaining water into the drain.
Rinse the sewer hose with fresh water if available on site or at the dump station. If you can, hang the hose somewhere to drip a few minutes - the coiled ridges retain a fair amount of water. Keep your potable water hook-up hose well away from the sewer hose to avoid contamination - fecal material is often loaded with nasties. Some of us spray the sewer hose ends, RV connector and such with a mild (10%) bleach or alcohol solution to kill stray germs. This is an especially good idea if there has been any spillage or leakage, but this should not be a common occurrence if you are reasonably careful. Stow the hoses in compartment, bumper, rubber storage container, etc.
LAST - WASH YOUR HANDS with soap and water. Just like your Momma taught you, right? Any hand soap will do, but rinsing with plain water will not kill any bacteria you may have encountered.