Generally, landlords pay the water rates and the tenants pay for their consumption of these services.
The prescribed tenancy agreement requires you to indicate whether the electricity, gas and water services to the rental property are separately metered.
Since all water consumed is chargeable to your tenant, you may want to share the costs of the water bill to encourage the tenant to water lawns and gardens. The prescribed tenancy agreement lets you identify what percentage of the water consumption costs the tenant is required to pay.