Ann: MD Presents at Mines & Money, Asia, page-10

Marine Traffic has the tugs practicing how to get the most out of each high tide. I went back and looked at the tugs performance and they often waited 6-8 hours to get in and out of that river due to tides. If we can have less time with two ships waiting out at sea costs will fall.[/QUOTE]
I believe with bigger barges and tugs that problem should resolve itself especially with a new mooring outside the river. They have to try and load 3 x 10000 t barges every second day- so a full ship every 4 days.
Everything will rely on the conveyor loading the barges assuming the trucks can keep up!