Powerhouse built in the early 1900s!

Camera and lens (if relevant) used to take photo
iPhone Xr

Location photo was taken (general location is acceptable i.e. county in Missouri)
Maramec Spring Park, St. James, MO

Please provide a photo or caption (250 words maximum):
This is one of the most popular and photographed structures at Maramec Spring Park. It was originally built in the early 1900s to provide electricity, but now helps manage overflow from the stock holding pool at the fish hatchery.