3.11 - Alternatives and options
- 3.1- Overview
- 3.2 - Method of evaluation
- 3.3 - Scope of analysis
- 3.4 - Stages of analysis
- 3.5 - Do minimum
- 3.6 - Travel impacts
- 3.7 - Costs of TDM programmes
- 3.8 - Benefits of TDM programmes
- 3.9 - Period of analysis
- 3.10 - Cost benefit evaluation
- 3.11 - Alternatives and options
- 3.12 - Sensitivity analysis
- 3.13 - Monitoring
- 3.14 - Selecting the appropriate evaluation method
- 3.15 - References
3.11 - Alternatives and options
Introduction
Evaluators must give early and full consideration to alternatives and options (sections 20(3)(d) and 68(2)(b)(ii) of the LTMA).
Alternatives are different means of achieving the same objective as the proposal, either totally or partially replacing the proposal. TDM programmes are generally alternatives to the provision of road capacity.
Options are variations on the proposal, including scale and scope of components.
Scale and scope of TDM options
TDM projects, like most economic programmes, will eventually have diminishing marginal benefit. There is an optimal level of implementation, beyond which incremental costs exceed incremental benefits. TDM programmes need to track these incremental impacts and limit such programmes.
For example, ridesharing programmes may be extremely cost effective when properly implemented, but once the potential rideshare market is satisfied there will be little additional benefit from simply expanding a rideshare programme, eg by sending out more promotional material. Instead, further expansion may require implementation of additional TDM strategies, such as commuter financial incentives, to expand the size of the market.
Similarly, cycling improvements can be cost effective where there is latent demand for this mode, but that does not mean that it is unnecessary to carefully evaluate investments in cycle paths to insure that they are cost effective; there may be better ways to support cycling, such as education and encouragement programmes.
Incremental analysis
The incremental analysis process for evaluation of options for TDM proposals is the same as the incremental BCR process described in section 3 of volume 1.
All effects (positive and negative) for which monetary values have been estimated should be included in the total benefits of the options when undertaking incremental analysis.
