A very common issue with the Evoque is that the air box drain valves perish and literally fall out. Land Rover do not sell a separate replacement, they will sell you a complete new air box at huge expense.

Without the valve at the bottom of your air box water, including normal  surface water, will be allowed to get into your air box which can lead to problems. Depending on your air filter type, this can become wet and cause your filter to fall apart, which can make its way down to your Turbo and destroy it, and very worst case allow water into the engine causing terminal damage.