I am a civil engineer with a masters degree in Water Resources, I truly believe that GIS has gotten very "scary" to the general audience, just as CAD did some 30 years ago. I would like to point out that CAD is definitely much more complex of a platform than a GIS platform is.
So what is GIS?
A) A georeferenced object representation ie.(point, arc, image)
B) A table or "metadata" ,which I find that it is a very scary word, that is attached to the object.
The different tools and "layerized" cutting, combining, intersecting, etc. generate queries which are just a "what happens if?" and are not in essence part of the platform. Some existed in CAD well before, like layers, surfaces ie. ("Triangular Irregular Networks"or .tin files which are older than I am. I am 40 right now and I think that contours are older than me, so no a .tin file is in no way part of the GIS mumbo-jumbo**s***
I truly believe that out of all the civil engineering applications, it is the Water Resources, Environmental Engineering and Tranportation Engineering that have benefited the most out of GIS. And in that order!
Particularly, Hydrology in which an H&H study or more specifically the physical "characterization" of a watershed is virtually an automatic routine in GIS and prior to GIS, it was one of the most tedious and challenging routines by hand. For that reason H&H studies cost half of what they did 10 years ago. Hydrology is one of the most "deceptively easy" tasks a civil engineer may find. Hydraulics is very simple and completely objective. Like all other civil engineering tasks which are relatively simple and they are all coded, which lets you sleep easy and not worrying if the building is going to collapse!!! A rapidly scoured bridge pile cap can happen while you blink and is not fun. I became a hydrologist because my aunt and uncle died during a storm in which a scoured bridge collapsed in the highway Apparently I took it very seriously and personal!
AA tip: Please do not think that big all inclusive gis platforms will last long. There are a lot of applications in gis that if you are not involved in the particular field, will never know of. These are being developed by graduate students ... do not waste your time and learn python instead. That is the cornerstone of this thing.