Stone and rock parapet of artificial water threshold on river in the flooding. Barrier over a large. Control flood waters reduce speed. An incredibly fast flowing raging. Giant roiling rocky thresholds mountain. Foamy dangerous wild boiling. Aerial drone small dam set embankment dike weir wall seawall riverwall barrage stream current flow effluent brook potamic fluvial rivulet watercourse riverbed overhead waterfall foam froth suds lather scum white spume jumping drop splash floor between rocks evacuation lifted liquid natural power rushing overflow that submerges land which is usually dry. High food deluge inundation channel artery beck horn flux course run inflow rapid speedy 4K UHD 3840×2160.