Dilemma in choosing the right masters course.

I have graduated from SIR MVIT college in bangalore in Civil engineering and I'm aspiring to do my masters. My main problem is that ican't decide whether to take up structures or environmental as my specialization.
Structures has always been the choice during my college days because that was the most popular. But now after studying all the various subjects i have found both to be interesting. Need to know more details and job prospects of environmental also. pls shed some light on this matter and help me choose the right course. thanks