I needed a dog-washing station for my Mastiffs, and after digging a shallow trench, I lined it with a vinyl liner, then put a standard perforated drain tube in, covered with gravel. All of this drains into the old septic system and leaches out to my yard. However, after scrubbing two dogs, there's no way I want to go indoors without a rinse, but then they're the nosy neighbors... So, I came up with a quick idea that gives a nod to the beach showers I've used. I recycled some scrap fencing we had, and used pallet wood to create the frame for the fence, and a couple recycled redwood garden border 4x4s. I painted and sealed it all, and have a place to hang baskets for cleaning supplies, drying herbs, or even pool towels and such. It's turned out to be very handy! In the background, you'll see the pallet fence my husband put up to keep the wet dogs from the car and air conditioning unit, haha!