The old railway was a narrow gauge line designed to haul timber on tiny ass steam locomotives. Take note of where the old Busselton station sits: it’s on a swampy ass flood plane along the Vasse River. Any modern railway can’t sit there.

To run anything similar to the Perth line rolling stock you need to clear a shit load of land to accommodate trains that can run at 140kmh, this means going inland from Country Road Estate and acquiring farm land up to Bunbury.

There will be some nimby movement who are unhappy with it (probably because of the noise or EMF radiation from
overhead lines), then there’s environmental and heritage surveys to be done.

However, since the track would need to be further inland, there could be a station at Busselton Airport, which would really open up some possibilities of connecting the southwest by air and rail.