Efforts to dislodge the slip above the Shotover River - estimated to comprise 200,000cu m of rock - appear to be having the desired effect, after significant movement was triggered yesterday.
Queenstown Rafting chief executive Vance Boyd told the Otago Daily Times volunteer firefighters were back at the site yesterday afternoon pumping more water on to the slip, which had led to the voluntary halting of all commercial rafting trips on the river since July 9, for safety reasons.
A section of rock estimated at about 150 tonnes fell while the crew was working.
"There's also quite a lot of slumping around the rear section that we're waiting to move," Mr Boyd said.
"The fire brigade will be back out [today], at the same time, we can still be running water down into it without actually being there."
The chunk of rock which fell yesterday had not caused any blockage to the river, he said.
"It's been like the rest of the pieces . . . it started off fairly substantial, but by the time they've gone even 50m they've broken up quite a bit."
Mr Boyd anticipated at least another week of site work.
If the slip had not failed within 10 days, the situation would be reassessed.
"We all hoped that there would be something fairly spectacular happen on the first day, but that wasn't realistic," he said, noting that ". . . pieces are dropping off and there is progress."
