Okobogee?

I was watching the first season episode of The X-Files called "Conduit" tonight. It's set in Sioux City, Iowa as well as Lake Okoboji. Or, as they spell it, "Okobogee". Apparently, Lake Okobogee is also set in the mountains, a misty lake surrounded by several hundred foot tall mountains covered in pine trees. The Okoboji Cam would suggest otherwise...