Starting at Ashlu Falls is 3.9 km long Ashlu Canyon[4] has several big rapids and large drops making it one of the best kayaking locations in the area.

[citation needed] A 49 megawatt run-of-river hydro installation below the canyon went online December 2009.

A diversion weir 5 km above the power house feeds water down a bored tunnel to the site.

It is owned by Innergex Renewable Energy and is expected to produce 265,000 MWh annually.

Ashlu Creek's only major tributary is Tatlow Creek, which flows northeast from remote Tatlow Lake and joins the Ashlu about 15.8 km below its source.