Yes, definitely we can first complete our graduation with B.tech in Civil engineering and then go for masters in environmental engineering.
For this, you can give GATE exam in the civil engineering subject, get a good score in GATE exam and then apply in different NITs and IITs for doing M.Tech in environmental engineering. There is a provision of changing the streams and you can easily do it.
Feel free to ask if you have any more queries. All the best!!
Candidates can check B.Tech Cut off for Top IITs & NITs here.
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