"steep river" is correct and usable in written English.
You could use it when referring to a section of a river that has an enhanced incline and is more difficult to navigate. For example: "The steep river gradually narrowed as the raft moved upstream."
The chain is cut by deep, steep river gorges, including that of the Rhumel (El-Kebîr) River.
They continued cultivating the steep river banks, and when the rains came there was heavy siltation of the system.
But those other renewable energy sources will require the development of a large number of available sunny desert spaces, windy plains, and steep river gorges.
The steep river bank strongly defines this park which doesn not touch the new center of town which is separate from the historic center.
There are no pylons to be expensively buried, no poisoned soils to be cleansed, and none of the steep river banks to be bridged.
To the east were the river ford and steep river walls where Arwen Evenstar summoned her elfin powers to wash away the evil Black Riders in a flood.
The one place you can find almost entirely natural ancient woodland is on steep river-cut ravines, where felling or any other sort of management is almost impossible.
They were preparing to surf a standing river wave in the St . Lawrence where high-velocity water roars over a steep river-bottom depression, pitches back and upward, and creates a waist-to-overhead breaker.
We taught an intermediate creeking class which is the kind of white water kayaking where they run waterfalls, very steep rivers and creeks.
Now it trundles again through the sheer-sided Aberglaslyn Pass, in and out of solid rock tunnels above the tumbling torrents of the Afon Glaslyn, Wales's steepest river.
The falls, on state-owned land, are part of the Boquet River, which is among the steepest rivers in New York State, said Robin Ulmer, executive director of the Boquet River Association.
