Here in this photo I will remove a few of the objects by using photoshop. An easy and good way to remove any buildings or isolate any docks that you do not want is to use is by using the quick mask mode. Quick mask mode is another way to select object without using any magic wand or lasso, but instead you can use the paint brush. This is useful because when lasso and magic wand tools do not work, the quick mask will most likely solve the problem. When using quick mask you can get finer selections by changing the size or hardness/softness of the brush. This allows for better selection for small and close object. Also you can select many objects at once.   But in this photo i will remove a few of the buildings along with some rooftops and also one of the docks.