The lacrimal lake is the pool of tears in the lower conjunctival cul-de-sac, which drains into the opening of the tear drainage system (the puncta lacrimalia). The volume of the lacrimal lake has been estimated to be between 7 and 10 µL. The lacrimal lake is the pool of tears in the lower conjunctival cul-de-sac, which drains into the opening of the tear drainage system (the puncta lacrimalia). The volume of the lacrimal lake has been estimated to be between 7 and 10 µL.