A heavy water plant could support a reactor for producing weapons grade plutonium.
The mature dragon-fly nymph, for example, makes its way out of the water in which the early stages have been passed and, clinging to some water-plant, undergoes the final ecdysis that the imago may emerge into the air.
Hottonia (water violet) is a floating water plant with submerged leaves cut into fine linear segments.
The valley is perhaps best known historically for the heavy water plant at Vemork that the allies destroyed during the second world war.
A. Caroliniana is a very small and curious water-plant, which floats on water quite free of soil, the tufts of delicate green leaves like tiny emeralds.