Not quite right the composition of those imports has changed. In 2010 we received significant imports form Africa and the Middle east. Now its mostly the US. However the total imports of oil is declining as western Canadian oil is offsetting imports.
That oil is coming in by rail.  
https://www.neb-one.gc.ca/nrg/ntgrtd/mrkt/snpsht/2014/11-01lmprt-eng.html