Aigües de Barcelona. Water company in Barcelona. Usually if you are buying or renting an apartment in Barcelona, you will have to either open an account or change the present account details for the water supply. This can be done on the telephone. You will need the contract number if it is an existing account. The water meter will usually be read when you take over the apartment. Sometimes in rented flats the owner prefers that the water account name stay the same and the new tenant just changes the bank account number so the the water bill is paid automatically by the new tenant's bank. Visit Aigües de Barcelona website for more information and contact numbers. The website is in Spanish and Catalan only. The customer service number is 900710710 and the emergency water number is 900700720