First, a minor correction to
1km x1 km, or 3333.3ft x 3333.3ft
; 1 km is 3048 feet, not 3333.3 feet.
"Cascaderailroad" has already outlined one way to get the drawing into TRS, but there are others, and before I'd offer an opinion which to choose, I'd need a little more information.
First, what are your capabilities? What image processing software do you know how to use? Did you produce the drawing yourself, or is it one you found somewhere?
Next, my hunch is that this is a drawing of an imaginary facility, but it would be useful to know the source and accuracy of the drawing. If I am correct, did you draw it, and what are your intended dimensions of items like the turntable, the length of the passenger station, &c? If it's a real location, does it still exist, or do you have access to the dimensions at the time you intend to represent? Is this an accurate scale diagram, or a general arrangement? What direction is North?
What is your intended use of this, and how accurate do you need to be? Are you trying to create something that will be merged with other items, or will this be part of a stand-alone route of your own?
ns