Here's a picture of the plaque on the Alton Bay floating bandstand. In all the times I have been around the bandstand in the winter, I never noticed it:
this is what the plaque states:
This Aquatic bandstand occupies the site of the original bandstand erected in 1920. It is believed to be unique. Restoration was completed in 1990 . Project was made by the citizens of Alton for all to enjoy.