How did they do the waterfall in Willy Wonka The Musical?

Answer 1

I did this show at a community theatre last year, and for our waterfall we had a large wooden structure with a ladder up the back, and one of our Assistant Stage managers would climb up the ladder and lower down a brown sheet and then rippled it to make it look like a water fall. Down below, a group of oompa loompas were holding up another brown sheet for the river.