Soper River - Fly into the remote mount joy runway and hike half a kilometre to the put-in and then follow the river down through Katannilik Territorial Park meaning “place of waterfalls,” apropos for an area where the water tumbles down its steep valley walls. The area is sheltered from the arctic winds making it a great location for wildlife and wildflowers to be found along with its many waterfalls along the river and in the canyon walls that it winds through.
due to the small plane being used to access the river most people use inflatable canoes and pack rafts to run the river, this also helps due to the potentially low water levels causing the need to portage at the start since the head waters have not fully joined with the river.
The majority of the river is class 1-2 but there are waterfalls along the river than can be portaged.
On a side note, I have never done this river but when my co trip plan creator and I were making our commercial trip plan we were following information from many sources such as Blackfeather and Nahanni so our information is mostly accurate but if you have any hesitations please use a guide as this area is very remote.