Bilayer lipid membranes are important biological barriers that envelope every cell and most cellular organelles; consequently, their physical properties under various biologically-relevant conditions are actively studied using in vitro model lipid systems. Extremely low hydration is a particularly challenging condition that living organisms have managed to overcome: Water content in plant seeds, as well as in brine shrimp cysts, 2 can reach just 2% mass weight. While waiting for rehydration, an organism must retain its internal structure, and the integrity of cells and organelles requires integrity of their membranes in the first place. Furthermore, in biological processes that require close membrane alignment, such as membrane fusion, local membrane dehydration occurs even under conditions of water abundance.