Energy Transfer Partners started moving oil through the much disputed but now completed Dakota Access Pipeline.  Capable of moving 450,000 barrels a day, it will reduce reliance on rail.  It will also further pressure tanker fleets.  Ocean tankers transport less than a third of all oil.  All the oil from the Mideast comes on tankers, BUT that quantity is declining – in April down 11%.  Combine this with an estimated 45 very large crude carriers and 61Suez Max carriers being delivered from the shipyards, and you can see depressed prices.  When I was researching this, I looked up “VLCC” – very large crude carriers, aka supertankers. Wikipedia tells us that they carry 2 million barrels of oil and often cannot enter the port fully loaded.  These ships can take on their cargo at off-shore platforms.  On the other end of the journey, they often pump their cargo off to smaller tankers at designated lightering points off-coast.