2015 is the third year in a row that BNSF has set a record capital budget. The railway says its capital programme for 2014 is expected to reach around $US 5.5bn, around $US 1bn higher than its 2013 spending.

The largest component of the 2015 capital plan will be the renewal of assets and maintenance, which is expected to cost around $US 2.9bn. BNSF says track renewals account for the bulk of these costs.

Around $US 1.5bn will be invested in capacity enhancement projects with a focus on the North Region, where the shale oil boom has resulted in a rapid rise in traffic, increasing the strain on the network.

BNSF will also acquire 330 new locomotives, which will increase the size of its 7500-strong fleet and allow older units to be retired.