Switching disciplines is common, Undergraduates often gravitate to one discipline or the other based on their "favorite" professor. As an undergrad I took both the sanitary engineering option (shows how old I am) and the structural option. I really wanted to be a structural engineer. I went on to work for a public agency that designed flood control channels. I never had an open channel hydraulics class. Well you take it on yourself to learn it. I went on to grad school to study hydraulic structures and hydrology. Then I moved on to a very large A/E firm in their civil engineering department. I did a lot of civil site work, storm drains and sewers for redevelopment projects, even storm drainage for a major airport runway. I was then handed a water supply and wastewater treatment for a major new college campus. I had to learn this. I never did water well design, or a treatment plant. I only had the elementary undergrad courses which only scratched the surface. I took it on myself to learn it. Get out the latest books, discuss with peers in the industry, vendors, etc. Eventually this is the type of work I specialized in.
My message is this is: if you are "missing something" and feel you would like something else -- do it. But you are going to have to spend the time and effort to do a lot of "learning on your own" so you can "walk the talk." There are resources out there. Attend some technical conferences and seminars in the area you are interested in, read the journals, some colleges have certificate programs where you can "brush up" through a course or two, get out to meetings of professional groups in your area. Find a job in a company that has your interest as one of their focal markets.
If you are a new graduate and you are uncertain, work for a small city or community that handles streets, curbs and gutters, drainage, sewers, traffic building and safety and see what interests you. An alternative is a large A/E company civil engineering department which will expose you to a wide variety of projects, particularly if the firm does commercial and public works projects. If you work for a specialized firm, e.g., structural, transportation, water resources, etc. you will not get exposed to other disciplines. If you are decided on what you want to do, these small specialty firms are ideal. But that doesn't mean you can stop learning.
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Joseph Reichenberger P.E., F.ASCE
Professor of Civil Engineering
Monterey Park CA
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