The phrase "wet pail" refers to soaking dirty clothes or cloth diapers in water before washing them, usually to help remove stains or odors. Full definition
In wet pail storage, the cloth diaper pail is filled with water and the used cloth diapers are left to soak in the water to aid in stain removal. (diaperjunction.com)
Does anyone have any idea where I can find a good wet pail? (diaperpincorner.com)
And some of them even used wet pails with a little bleach. (clothdiapergeek.com)