Is it permissible for the landlord to add his transportation costs to the water authority to the water bill and divide them among the tenants, or should he bear them himself as the owner?

It is not permissible to add transportation costs except with the knowledge and full consent of the tenants, because a Muslim's money is sacred and not permissible to take except with his full consent, as the Prophet, peace and blessings be upon him, clarified in his Ahadith.