How do you wash waterproof pants?

Washing them by hand is the best way to do it without damaging the material or stripping away the waterproofing. Fill a bucket with cold water and add a gentle detergent into it. Make sure you use a ‘mild’ or ‘delicate’ detergent that doesn't contain additives like fabric softeners, fragrances, whiteners, or colorants. Then, dip each pair of pants in the water and swish them around to make sure all parts of the pants are wet. Rinse the pants with cold, clean water until there aren't anymore suds and the water runs clear. Finally, squeeze the pants to remove water. Don't wring or twist them or you could damage the material. When you're finished, you can hang the pants up to air dry for the best results.