Smoke water
The smoke water , also Drängewasser called, referred to water, which under one by flood is accumulated dike transpires and rises at the air side of the dike from the ground. This phenomenon can often be observed on coarse-pored, sandy-gravelly ground. It often rises to the surface in a relatively concentrated manner immediately behind the dike and forms temporary shallow waters. Sometimes the water escapes "bubbling" or "smoking" because air stored in the ground is pushed up. Where there are very high amounts of smoke water, a smoke dike is sometimes created in parallel on agricultural areas on the land side of the dike in order to secure the wider area.
Large amounts of smoke water can jeopardize the stability of the dike and therefore require rapid action.
In nature reserves , smoke water can be desirable, as it can be the basis for the preservation of biotopes in the former floodplain. On the middle Elbe , where temporary smoke water occurs particularly frequently, there are, for example, habitats of amphibians, which are rare elsewhere, such as the fire-bellied toad , the moor frog or the tree frog, as well as refuges for tadpole shrimp .
The rest of the water that presses through a dike during flooding and emerges from the inner slope is called drainage water, Kuver water, Köhr water, spring water or sweat water.