There are two turn of the century hydroelectric plants a fairly short walk upstream from the falls on the Canadian side that are worth looking at in case you might be interested in photographing them. Briefly, the Electrical Development Company one that sits right on the river was built by Sir Henry Pellatt of Casa Loma fame and the building was designed by E. J. Lennox, who designed Old City Hall among other things. Sadly, the building's in rough shape because it's received next to no maintenance for many years. The other one's on the inland side of the parkway and it's owned by Canadian Niagara Power and it's in excellent condition.
I took a trip down to Niagara Falls with a friend of mine back in 2005 and photographed these plants on Kodachrome film along with the usual Niagara Falls stuff. We were lucky and actually met one of the Canadian Niagara Power employees outside the plant while we were photographing and he invited us inside for a brief tour of the 100+ year old operating electric plant. It truly is in beautiful shape, unlike the E. J. Lennox building across the parkway, and from having met and spoken with some of the staff there, it's clear they took great pride in keeping it in excellent condition. Unfortunately, I think the plant's been retired between then and now but that tour really made the day for me both as a photographer and an electronics engineer. I'm hoping to go back to Niagara Falls later this summer or maybe the fall to visit some of the same locations again and shoot some black and white film.