tributary

The dam's construction on a Nile tributary, which provides most of that great river's water, was controversial with downstream countries.

Enforced by police, the ban carries potential prison time for those caught fishing right along the Yangtze, as well as adjacent lakes and tributaries.

More than a mile long and 145m high, the dam is on the Blue Nile tributary in the northern Ethiopia highlands, from where 85% of the Nile's waters flow.

Members of the tribe say they are celebrating the return of their ancestral lands along Blue Creek, a major tributary that meets the Klamath about 40 miles south of the Oregon border.

White water rafting, kayaking and canoeing: The Trinity River, a 203-mile tributary of the Klamath River, starts in the Trinity Alps and features calm waters and multiple classes of white water.