I went back to the fountain today. Much of the ice had melted with our 2 days of warmer temps but there were still some nice formations to photograph. I used my 400mm this time instead of the 70-200 so I could stand back from the blowing water spray and still get some close-up images.
Canon 40D, EF 400mm f/4L
f22 @ 1/160th, ISO 200
Manual mode, pattern metering, handheld, fill flash
ACR/CS5, Topaz Infocus for sharpening