Hi -
I want to build a freestanding privacy wall, about 64" tall and 16'long, to screen our hot tub from neighbor's view. I'll be using the retro "pierced" blocks that are one square foot and 4" thick. Will use 8"x8" blocks
for piers at either end, and 8" x 8" x 16" blocks for center pier. Closest example picture I could find online
is attached.
Question is about footing. I'm in Minnesota. Do I need a poured concrete footing 42" deep (frostline) and 16" wide, for the entire length of wall? Or is there another option?

Thank you!http://www.flickr.com/photos/mikesmcm/4342396990/in/photostream/