The Columbia River
The Rio Grande River flows along the border of Mexico and the United States of America. It flows along the border of Texas.
the river that flows along the western border of the district is the kwilu river
Danube
Barrier island
Ohio
Columbia river
Barrier island
The Amur River flows mostly through China, but a portion flows through Russia and along the border of China and eastern Russia.
If you mean the Columbia River along the Oregon/Washington border, The river rises in the Rocky Mountains in British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean.
The Snake river flows east for part of its course and the water eventually flows into the Pacific Ocean. It forms part of the border between Idaho and Oregon The Columbia river forms most of the border between Washington and Oregon, but the water in it flows WEST, so unless you meant something like "runs in an east-west direction" the Columbia is not the river you are looking for.
Columbia River.
Columbia River.