BWSSB Fees before Plan Approval

[averagejoe]

I have been told by my BBMP Approved engineer that I need to submit a challan paid in the name of BWSSB for Rs 24,000 . This challan is to be attached along with other documents while uploading all documents for Plan Approval.
I went to BWSSB office in Kundanahalli and was told to go to Cauvery Bhavan?

Can anyone suggest why it is for & Where I am supposed to pay this? Can I pay this online or in a Syndicate Bank?