The Elk River is a classic East Kootenays run with great whitewater that runs through an interesting low-slung bedrock canyon. While an endless stream of photos of the near perfect waterfall called Leap of Faith found at the end of the upper run have raised the profile of this river in recent years, it's the collection of clean and challenging rapids upstream of that really make the Upper Elk shine. It is a very nice piece of whitewater. The only downsides are that it's quite short, and there aren't many other runs of similar difficutly close by at the times of year it's running.
The closest town to the Elk is Elko, which is a small town about 15 minutes west of Fernie on highway 3. The river essentially flows behind the large sawmill in town. Use this map to get your bearings - the directions on Paddling ABC are also good. The put in is located either in Elko at a bridge over the flatwater above the diversion dam at the start of the run, or right at the dam. It's possible to finish the run off with a steep hike out of the canyon below the Leap of Faith waterfall, but it's easiest and more fun to just paddle down through the Middle Elk to get a few more rapids in. There's still a hike out but it's not as steep.
The Upper Elk is runnable at low flow times of year (spring and fall seasons). There is an old BC Hydro run-of-river power facility that partially dewaters this section of river, but as of 2016 there might not be any power generation or water diversion occuring as the dam is quite old. There's currently no plan to fix the dam. 20-25 cms when there is no water being diverted is in the medium range. Note that if the powerhouse is diverting water (up to 25 cms) it will be harder to predict the flow, and more water will be required on the gauge to make up for that removed by the dam.
The Upper contains about half a dozen pool drop style rapids and some class IV boogie. Just below the dam is a cool slide, which is shortly followed by the first class V rapid, a ledge called Horseshoe. A few smaller things lead to the biggest rapid on the section called Caveman (or rather un-originally, Triple Drop). Here, two ledges lead in to a powerful river wide hole where some of the outflow feeds into a cave eddy. There is a hard portage down river left, with a permanent chain ladder installed to help with some down climbing. Almost directly below Caveman is a portage around a dangerous/unrunnable rapid that's worth scouting before putting on if you've never done the run before, and then you're at Leap of Faith and the start of the middle section. Enjoy the freefall!