The first and most important for night urban photography is to take pictures during dusk. If you photograph after the sun has fully set behind horizon, you will get dark, really black shadows (like in your photo above), and very bright spots of light. The best time for photography is dusk (or dawn, too). For examples of good timing cnonditions I am talking about, see here and here.
Urban photographs usually expect large depth of field, therefore are often shot with a small aperture. This is when the star trailing appears on bright spots of light, like in your photo above. You could, e.g., take another photo with the lamp in focus and then overlay it locally. Otherwise shooting both lamp without a star trail and smooth water surface with one picture is problematic.
Night shots are often done with HDR. Here when I talk of HDR I do not mean those acid HDR shots found often on the Internet. Any photo which has been constructed from more than one image with different exposition is considered an HDR. SO, you can take two photos, one of the pool with water with a narrow aperture and long shutter time, another of the building with a larger aperture, and later stitch them together in Photoshop using masks.
If you want to achieve a longer shutter time with a lot of light in the scene (e.g. a jungle waterfall), then you will not get around without an ND or a polarizer filter.