Proponents of the Transmountain Pipeline Expansion (TMX) promise about 34 Aframax tankers will depart each month from the Westridge Marine Terminal on the Burnaby section of Burrard Inlet. After TMX comes on stream, the number of Aframax or Panamax oil tankers visiting Vancouver will rise from about 32 to an estimated 380 Panamax and Aframax tankers or just over one per day. 

But, can we trust anything Trans Mountain tells us? This is the company that estimated the project would cost $5.4 billion. In March 2023, the budget for the still incomplete project stood at $30.9 billion. The company initially said construction would be complete in 2019. It expects TMX will be operable in 2024.

Aframax tankers burn about 45 tonnes of marine fuel per day and the round trip between China and Canada may take about 50 days. That requires around 2,250 tonnes of fuel for each trip. Thirty-two tankers would need 76,500 tonnes (170 million pounds) of fuel. Marine heavy fuel oil is approximately 86% carbon, which implies about 3.15 tonnes of CO2 per tonne of fuel consumed.

A typical passenger vehicle produces about 4.6 tonnes of carbon dioxide per year.