Jeff Foott / Indian Rhubarb (Darmera peltata) growing on rock in river, Cascade Creek, Yosemite National Park, California

Jeff Foott / Spring run-off, Cascade Creek, Yosemite National Park, California

Jack Dykinga / Cibecue Creek waterfall pouring through canyon narrows, White Mountain Apache Reservation, Arizona, USA

Colin Monteath / Waterfall below Mount Fitzroy, Los Glaciares National Park, Patagonia, Argentina

Colin Monteath / Waterfall at dawn below Mount Fitzroy, Los Glaciares National Park, Patagonia, Argentina

Chien Lee / Stream flowing through pristine lowland rainforest in Gunung Mulu National Park, Malaysia

Jeff Foott / Spring run-off, Cascade Creek, Yosemite National Park, California

Jeff Foott / Spring run-off, Cascade Creek, Yosemite National Park, California

Jeff Foott / Incense Cedar (Calocedrus decurrens) trees and waterfall, Cascade Creek, Yosemite National Park, California

Jeff Foott / Cascade, Avalanche Creek, Glacier National Park, Montana

Jeff Foott / Cascade, Avalanche Creek, Glacier National Park, Montana

Jeff Foott / Spring run-off, Cascade Creek, Yosemite National Park, California