An interesting point is the busiest time every on the Alamosa-Durango line in terms of train movements and tonnage handled occurred in April of 1952 at the absolute peak of the pipe boom.
Every train was a 70 car maximum tonnage affair. One train double headed each way between Durango and Chama (4 engines in use), One daily train to Farmington (1 Engine). One west bound from Alamosa to Chama (2 engines). A constant parade of hill turns from Chama to Cumbres (3 engines per turn). This was all accomplished with 1 K-36 (488) and 10 K-37's.
484 was in the Alamosa Shop for overhaul. 480-483, 485-487 & 489 were up in Salida - Gunnison area. Mostly unused.
473 was in Alamosa being rebuilt after going into the Animas River the previous summer, 476 had been torn up badly in a derailment on the Silverton Branch bucking snow.
478, 463 and 464 were trying to buck out the Silverton Branch. 453 was the Durango switcher.
488 was used as the regular engine to Farmington, leaving the 490's the handle all the Alamosa-Durango traffic.
THAT would have been the time to be train watching on the 4th division......
Help arrived that summer when 487 was shipped south.