That looks nice. I really like the double falls, nice job! That is a good sized project. As far as the picture goes, it is better than a lot of night time shots I have seen. It does appear a little grainy, which is a product of a high ISO setting so you can have a short shutter speed. I don't know if you have a camera that will allow you to shoot manual settings, but try setting your ISO (speed of digital film) to 100 or 200 and using a good tripod with the auto shoot timer on your camera (this will eliminate camera shake and a fuzzy picture.) If you are just beginning to shoot you might set your camera aperture to around f7, this is a good average, medium distance focal length aperature for twilight shots. Depending on how dark it is you may need to set your shutter speed to 3-8 seconds or longer if it is fully dark.
Just a few hints for you. Your composition is good on the photo. Don't be afraid to find some small detail items that are very cool and get some close-ups. Sometimes, things that seem insignificant by day will dazzle under the warmth of soft landscape lighting.