Which college should I join for UG civil engineering: NIRMA or Banglore Institute of Technology? Kindly suggest as I have no other option.

You must try for All India category in Nirma University and as you're scoring 80,000 rank in Mains I would also suggest you fill up the Bangalore Institute of Technology form lest you don't get admission in Nirma. Nirma also provides NRI category for 15% of total seats available. But that costs doub