Top view of a table made from two trees, two poles, and several shorter spars
A camp sink need not be any more than a few large containers placed on a table. For the containers, you can use a large salad bowl or a plastic storage tub. The table to place them on can be constructed by finding two trees at least 20 cm in diameter and about 2 meters apart. Then using square lashing, attach two long poles to either side of the trees, at waist-height. Use continuous lashings to lash several shorter poles across the support poles to make the table surface. The short poles should all be as close to the same diameter as possible, or if that's impossible, arranged from smallest to largest.