impermeable -
preventing especially liquids to pass or diffuse through; "impermeable stone"; "an impermeable layer of scum"; "a coat impermeable to rain"
permeable allowing fluids or gases to pass or diffuse through; "permeable membranes"; "rock that is permeable by water"
imperviable,
impervious not admitting of passage or capable of being affected; "a material impervious to water"; "someone impervious to argument"
tight affected by scarcity and expensive to borrow; "tight money"; "a tight market"
retentive having the power, capacity, or quality of retaining water; "soils retentive of moisture"
