Good continuous grade 3 run that ends with 100m of grade 4 just above the confluence with the Tees. The final stretch (including Rokesby falls) is difficult to inspect/portage, so be prepared to read and run.
Putin at the bridge in Rutherford. Takeout after the confluence with the Tees: the first available takeout is river left just above Whorlton Lido (clamber up the steep bank), or continue on the Tees down to Winston Bridge as it will be at a fun level if the Greta is running.
Rainchasers is best experienced as an app.