Rivercourse

Now I was far more likely to dream about the fauna around Lake Kiboko, the wildflowers along the rivercourses, or my relationship with Helen.

Source: wiktionary

While he crouches on the hard clay of a dry rivercourse to eat his pack lunch, he thinks: If I had no other way to describe what I saw in the crevasse?

Source: wiktionary

So we shoulder our daypacks and trudge warily along the muddy rivercourse towards the tumbling snarl of the Kapichira Falls.

Source: wiktionary