The CCN number can be get from the previous water bills. The Bottom left hand side you will get a number including some alphabets.
The Brihanmumbai Municipal Corporation (BMC), also known as the Municipal Corporation of Greater Mumbai (MCGM) or the Bruhanmumbai Mahanagar Palika, is the civic body that governs the city of Mumbai and is India's richest municipal organization.The BMC's annual budget is even more than that of some of the small states of India. Established under the Bombay Municipal Corporation Act 1888, it is responsible for the civic infrastructure and administration of the city and some suburbs of Mumbai.
The Mumbai Metropolis has a historic tradition of strong civic activism dedicated to the cause of a better life for all its citizens. And it's the Municipal Corporation of Greater Mumbai (MCGM), the primary agency responsible for urban governance in Greater Mumbai.
Mumbai Water bill status and Payment
The other services like Register complaints, water timings etc can be viewed in the below official site.