This is why special "helper engines" (also dubbed "Bankers") are often stationed near steep grades on otherwise mild tracks.
It is cheaper than running a more powerful (and thus more costly) locomotive over the entire track mileage in order to make the grade, especially when multiple trains run over the line each day (to help justify the fixed daily cost of the helper operation).
This means the "ruling grade" may change if the management chooses to operate the railroad differently.
But nowadays the railroad doesn't base helper engines at Wells so trains must leave Sparks with enough power to climb the 1.4%, making that the division's ruling grade.
In the United States, Congress set the Standard Grade for railroads eligible for subsidies and grants in the 1850s.