What is the sink? Does it have a kitchen size opening for drain?
P trap for cargo camperThis will keep odors out. If gone on ebay, for those reading a few months late, use "JR Products Exterior Drain Trap RV Camper Concession Sinks" for search terms and it will come up.
You can use a flexible hose to route to your exit. A hose works, but a hose will kink, so get that plastic spiral hose which will not kink.
I just run mine out a hole in the floor to the ground. If you are racing you are in fields? No one will know, or care. If you want to collect it just put a bucket outside under the hose.
You can also route it to a bucket inside and under the sink. Or a portable 5 gallon fresh water tank, just cut a hole big enough for the hose to fit through in the containers's fill lid. Maybe a new lid with no hole for travel. A water bag also work, anything almost will work to catch sink water.
2 days of sink water will not be a bad smell, especially if it is not in an airtight container. It won't smell good, but ...
