BNSF Railway train H-SDGBAR1-22 (High Priority Merchandise - today it is all autoracks - heading from San Diego to Barstow) crosses Santiago Creek as the train passes from Santa Ana into Orange, Cailfornia, on July 22, 2017. This train departed San Diego shortly after noon on BNSF's San Diego Subdivison, and almost immediately transferred to San Diego Northern's San Diego Subdivision. At the Orange County line the trackage became Metrolink's Orange Subdivision, and just about a mile ahead this train will divert to Metrolink's 5.5 mile Olive Subdivision. Then it is on to the BNSF's California/Los Angeles Division (where it will become just another freight, unlike on the rest of this trip in which freights are rare) to San Bernardino. Then this train operates on BNSF's busy Cajon Subdivision (over Cajon Pass, of course) to its destination of Barstow. This train is short today, and a pair of new ET44C4 diesels (BNSF 3752 and 3756) is enough power to get it all the way to Barstow.
Tier IV locomotives are the safest, cleanest, and most fuel efficient locomotives on the rails today. Unfortunately, most of them are ugly and are as quiet as an ACS-64.