Bangalore Water Supply & Sewerage Board [Bwssb] — lack of transparency in cauvery bill

Address: 560048

Website: bwssb.gov.in

Hi,

I am writing to request for a clarification on the bill being charged by bwssb for our apartment, rr # e-229122.

I see multiple heads being charged in the bill - water charges, meter charges, sanitary charges & other charges but there is no explanation on what these charges are. What falls under 'other charges'?
Also, i see a remark 'levy of stp charges levy of rwh charges', what does this mean?
To top it all, the sum of the amounts mentioned under all the above 4 heads doesnt match the total bill amount. See below for example from the latest bill - june'18

Water charges-4730
Meter charges - 300
Sanitary charges - 2800
Other charges - 3765

Even if i add all these 4 heads (Though i am not clear what other charges is), the total comes to 11, 595 but the total bill amount is 15, 360. Why is there this difference? This has been happening every month looks like since the start. Why is there no transparency and clarity in the billing?