With respect, NO! Straightening curves definitely can improved transit times, which is why HSR tend to have curves around 9 km radius. Easing gradients does not do this. The prime example is the Melbourne Sydney line in NSW, where to ease gradients substantial curves were added. As you travel by train, you see the ends of embankments and cuttings which gave a reasonably straight line, but the curves were added to keep the ruling gradient down – all the weak steam engines could cope with at the time. Now the line should be straightened, use the old route. The Paris Lyon LGV has substantial gradients – easier to go over than around – and at at least one point you can actually feel lighter as the train goes over a summit at 280 km/h.

In NSW half an hour could be cut off the time if the Hexham-Stroud deviation were built, but at present the BC ratio is shaky.

Certainly there are better uses for the HSR money – supposing it actually existed. First should be in Sydney, restoring the tram services with modern trams on major travel corridors – Parramatta Road. Anzac Parade, and Military Road, for example. Substantial cost reduction plus time savings should give a substantial positive BC Ratio. Same with the Doncaster Light Rail in Melbourne.

IIRC Bent Flyvjberg’s main work was on the construction costs. He correctly identified that costs were greatly underestimated on some projects. But rather than responding by working to bring actual costs down, the most common response seems to have been to inflate cost estimates. And that’s certainly the approach they took with the Phase 1 study.

As for staging slowing the flow of benefits, of course it does…but not in proportion to the relative cost.

Research by experts like Bent Flyvjberg shows the reverse: costs of major infrastructure projects tend to be under-estimated and benefits over-estimated. Shareholders in Brisbane’s Airport Link could testify to that.

Be aware that staging slows the flow of benefits too.

Bellistner #21:

As you say, all that foofaragh (brilliant word BTW) over the NBN when, unlike HSR, it’s intended to not only fully cover its operating costs but pay back all its capital costs and return 7% p.a. to the government!

On a cost-benefit viewpoint, it is far better to improve PT in the major cities (including bringing back trams to Brisbane) and performing inceremental improvements to the existing rail corridor. Just straightening Yass to Albury might shave an hour off transit times between Sydney and Melbourne. Semi-High-Speed Rail (like QRs Tilt Train, or what NSWs XPT was intended to be) is doable, at a modest cost, on current alignments. The much-derided ARTC, with some additional funding, could bring forward planned track improvements, instead of the current system of ‘just getting by’ and performing oh-so-gradual repairs to an interstate network left to rot by successive State Governments. Straighten curves and easing grades are a cheap and quick method of improving transit times.

While many of the spends could be justified as a Public Transport issue, a side-benefit (and in actuality, probably the main one) is improved transit times and access for rail freight, something that would actually measurably reduce emissions and external costs, even more so if the network was electrified and run off renewable power (think hydro rather than wind).

Not all cost saving measures reduce performance. The phase 1 report made some crazy claims about station costs and even went as far as considering building termini in silly places like North Melbourne to avoid the cost. The logical cheaper solution would be to flog a few of the existing platforms in Melbourne Southern Cross and Sydney Central. Admittedly when the track is extended beyond Sydney there would be a requirement for new underground platforms as well, but not many.

Many high speed railways overseas have opened in stages. Would a train running very fast to Campbelltown NSW and then moderately fast for the final stretch into Sydney be so bad? The expensive last stretch, which would probably require a lot of tunnelling, could wait until demand can be shown to justify it.

Studies tend to underestimate benefits of such projects because after 30 years (or however long they consider) the infrastructure will not only still be around but will be more valuable than ever. Similarly they tend to overestimate costs by setting the discount rate too high.

The obvious non-gold plated option is to have a moderately fast train. But that’ll lower the benefits too.

The way you take P10, P50 & P90 all depends on the appetite for risk and procurement delivery mechanism.