The costs and benefits of such a proposal concern us all because we all pay taxes (via the GST).

Sandy Bathgate highlighted the need for "rigorous examination of costs and benefits" in his letter (We Need Rigour, Not Rhetoric, July 10).

Transport planners use a concept called a Benefit Cost Ratio (BCR) when considering projects.

If a project has a BCR that is greater than 1.0, the project is expected to deliver benefits to the community greater than the costs.

If the BCR is equal to 1.0, the expected benefits will equal the costs.

If a project's BCR is less than 1.0, the project's costs outweigh the benefits, and it should not be considered.

Here are some BCRs taken from the Central West Transport Needs Study (2009):

Main West Rail Line (Lithgow to Parkes): "greater than 1."

Newcastle to Dubbo rail line: 1.63.

Bells Line of Road Expressway: 0.01.

Questions: Why are we even considering the Bells Line of Road expressway?

Why hasn't the Newcastle to Dubbo rail line been completed given its high BCR?

Why hasn't the Lithgow to Parkes rail line upgrade been started given that the benefits of that project will outweigh the costs?

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