Plan B
Once the original task of removing the loose rock had been ditched, the engineers came up with a different plan to solve their problem. Plan B was to raise the level of water in the basin. This would mean that water from the Falls was pushed above the loose rocks, instead of through them.
As quickly as it was suggested, however, plan B was dropped, as the locals who were reliant on the tourist industry around the Falls were concerned that this would affect the look of the spectacle, and reduce visitors. The engineers had to find another solution; on to Plan C!