Levels of demand are crucial to the economic viability of infrastructure initiatives. Infrastructure Australia needs to understand the basis upon which demand estimates have been created. For each initiative, the following information should therefore be provided:
1. A comprehensive list of the detailed assumptions which drive demand, including the rate of population growth, employment growth, private vehicle demand, public transport demand; and how these change over the appraisal period;
2. The underlying justification for these assumptions and growth rates, particularly the expansion, annualisation and extrapolation factors used and sensitivity testing of core assumptions such as Gross Domestic Product (GDP) growth rates;
3. Detail of any changes in land use with the initiative such as residential densification or Transport Orientated Developments (TODs) assumed in the demand modelling, including any commitments to rezoning or other planning law changes which would be necessary to facilitate those land use changes;
4. The methodology used to estimate demand - the nature of the transport model used and how 'knock-on' and wider network effects are calculated; plus an explanation of the independence of forecasts and the degree of external or independent scrutiny of the forecasts. This should include full details on how the model forecasts 'generated' demand; and
5. A detailed disaggregation - by year, date and user type - of the results of the demand modelling, including all the information set out in Appraisal Summary Table 2 below.
Typically, this information will be contained in a detailed transport modelling report, which will have been prepared by proponents for initiatives. Wherever possible, in addition to completing the tables included in Appraisal Summary Table 2, proponents must submit this report and then provide page references to the key sections containing this information.