This shot of the Norris Dam was taken on a cloudy, overcast night. I did not use any filters, I did use a tripod for the long exposure. The lights from the dam were reflecting nicely on the water.

Camera: Nikon D7000
No Filter
Tripo: Manfrotto
Focal Length: 18 mm
Shutter Speed: 30/1 sec
Aperture: f/22
ISO: 250