Airport rail study was doctored to ensure sunshine won route shortlist

Financial estimates for the Melbourne Airport Rail Link were altered to ensure the Sunshine route appeared cheaper than alternative options. A confidential submission presented to the Big Build royal commission revealed that a secret working group was established to influence the project shortlist.

The planning expert who advised on the rail link said in the submission that public servants inflated the price of the route running through Maribyrnong. The changes included adding 3.5 kilometres of extra tunnelling that added up to $4.6 billion to the cost of alternative proposals, making the Sunshine alternative look more favorable.

The inquiry was told that the working group operated under instructions given by then public transport minister Jacinta Allan. Members of the small group were directed not to diarise meetings or discuss their ongoing work with colleagues outside their immediate circle.

The allegations challenge the integrity of the business case behind the joint funding commitment from state and federal authorities. Testimony presented to the commission indicated that a senior public servant was threatened with dismissal if the preferred outcome of selecting Sunshine was not achieved.

The findings emerge as political parties prepare for the upcoming state election. The disputed planning process affects major transit investments across Melbourne and surrounding suburbs, raising fresh questions about transparency in public infrastructure projects and spending.

Submissions continue to be reviewed by the royal commission as hearings progress. Officials involved in the original transport assessments face renewed scrutiny over how transport corridors were evaluated before government announcements were made.

The royal commission continues its detailed public hearings into transport infrastructure planning across the state this week.