burn drain drainage flow flowing gentle heather highland pour river rock rocks scotland stone stones stream trickle water white dangerous drop fall fast fierce kjosfossen natural nature norway norwegian powerful raging spray thunderous violent waterfall cliff channel control current dam depth electrical England english gate level lock manage management power powered regulate regulation thames bend dune dunes grass marin perspective sand sandy atmosphere background city cooling crossing damp downpour drenched drenching footpath gray grey heavy-rain outdoor outdoors path pedestrians pelting-down pouring-down pouring-rain rain raining roadside Singapore spatter spattering splatter stormy streaming street street-scene textures tropical umbrellas unprotected weather wet wind canada cascade conifer descend forest hillside plunge Rockies Rocky Mountains Tangle Falls tree waterfalls