Equivalent Tenements Explained
An Equivalent Tenement (ET) is a measure of the load a property places on the sewerage system. One ET is considered to be the sewage discharge from an average single residential house, under dry weather flows. This has been determined to be 200kL/ET/annum. ET rates for different land uses are calculated as being a factor of this average sewage discharge rate.
In relation to non-residential properties, different ET rates are applied to various property attributes, including building area, land size, number of occupants, general public entertainment facilities, hospital beds and amenities. These ET rates and attributes are then used to undertake an assessment of the number of ETs for that property.
Where a property has multiple activities on the land parcel the ET rates and assessment are based on each specific type of activity.
This list of categories is not exhaustive and consequently TasWater has included the ability to assess on an ad hoc, case by case basis if the circumstances warrant.
It should be noted that discharge of non-domestic liquid trade waste is recouped separately through the application and payment of trade waste charges.
Our approach is underpinned by the Section 64 Determinations of Equivalent Tenements guidelines produced by the NSW Water Directorate and available here. The NSW Water Directorate guidelines indicate it is preferable to apply localised ET figures as there are variances in differing jurisdictions. TasWater has adopted statewide ET rates, consistent with the application of postage stamp pricing across the state, and made adjustments to some rates to best reflect Tasmanian circumstances. Our justification of ET rates for property types that differ from those contained in the NSW Water Directorate's 2017 Section 64 Determinations of Equivalent Tenements Guidelines are available.