Kerala Water Authority — bill amount

Address:

Thiruvananthapuram, Kerala, 695543

This is a complaint related to bill # 37209239
Consumer : m vijayalekshmi
Jayakrishnna, kannampally, vellanad

Consumer # [protected]

Bill date : 19-june-2018 reading : 848 kl : 45 (2 months water consumption)

In the bill : water charge : 628
Additional charge : 64 (Inspection charge)
Bill amount = 628+64 =692

Complaint :
1) why is this inspection charge and on what ground its decided? Its unfair to charge without detailing.
2) what is the slab to calculate the bill amount? There is drastic variations in the bill amount