Two water bills in Auckland apartment?

Does anyone living in Auckland apartment pays for two water bills? 1st one is monthly for hot water from provider (roughly $60) 2nd one is every four months for cold water from landlord (roughly $400) I’ve never heard something like this before.. can anyone explain why the water is billed separately from different sources? Thanks

FYI- Only two people in the household. The bills seems to be quite high to me.