The orange is actually from street lights shining from railings on the bridge above; the blue is a combination of lighting under the bridge (both direct and reflected off the water) and the blue sky before sunrise.
This was cropped from a shot at 100mm - I'll have to go back and shoot it again at around 120-130mm, for a higher-resolution image. The good thing about static scenes like this is that they don't change over time, and almost every flight out of Australia goes through Singapore...
