"expanse of river" is a correct and usable phrase in written English.
It refers to a large, open area of water that flows continuously in one direction. Here are a couple of examples of how it could be used in a sentence: - "As we reached the top of the hill, we were met with an expanse of river stretching out before us." - "Her childhood memories were filled with afternoons spent playing along the expanse of river that ran through her hometown."
Beyond it was the smooth expanse of river.
Through the cracks could be seen a wide brick walkway, beckoning across a shimmering expanse of river.
It sat isolated alongside a very wide expanse of river, warning boaters away from the stretches of water to its west, which are only a foot or two deep over sharp rocks.
In eight years, residents of the 37 trailers that are parked alongside a glorious expanse of river, with million-dollar views they enjoy for a relative song, will have to move out.
There was a wide-open expanse of river with no boats in sight, and several hundred yards to the other side, on the cliffs of southern Riverdale, a big blue "C" had been painted in a show of support of the Columbia crew team, which has its boathouse nearby.
An unbroken expanse of river and sky.
During stable flow conditions, Ph. autumnale mats proliferate, at times forming expansive black/brown leathery mats across large expanses of river bed (Heath et al. 2010).
Traveling by boat, we'll lose the open expanse of the river and maneuver instead through a flooded forest.
Roads and picturesque cobbled walkways in the French capital have disappeared, submerged by a vast expanse of brown river water carrying an unusual assortment of debris including logs, big wooden planks and a metal sign from a boat-club in its angry, swirling current.
I put the rods in a rack, stood up behind the console, pushed the throttle down and turned toward Haverstraw Bay, a wide open expanse of the river about five miles wide where Henry Hudson once stopped to dine with local Indians on shore.
We drive and experience proper dropped jaws when we turn off the motorway and arrive at the first viewing point: from high up, all you can see is a vast expanse of broad river and enough grapes, it seems, to keep the world drunk for ever.
