UN136: Too good? Will better buses break the train system?

Over the last three years I've been proposing area by area bus network reform through the Building Melbourne's Useful Network series. Each week I'd appraise a local area's bus network, look at service gaps and outline a revised network. These were progressively plotted onto an interactive map. 

Confusing backtracking, routes stopping short of popular destinations, wasteful route overlaps and restrictive timetables common in the current network would be replaced with simpler, more direct and more frequent 'Useful Bus Network' routes. Timetables would be more even 7 days per week and hundreds of thousands more people and jobs would be walkable to buses every 20 minutes or better. 

Revised networks typically involve some added costs though these would often only involve extra operating hours (ie 'working the fleet harder') rather than new bus purchases.  Because we have had so little bus reform in years fixing this backlog would deliver huge mobility benefits right across Melbourne for an affordable price. 

A boost to every 20 minutes would be a large service uplift by Melbourne bus standards. But is still not the sort of exciting turn-up-and-go service that main roads and key destinations deserve. To address this I upgraded the interactive map to include 963 km of frequent bus routes operating every 10 minutes or better with inspiration from the DoT's 2006 Principal Public Transport Network, existing SmartBus routes and some upgraded Useful Network routes. I called this the Future Frequent Network, intended to be introduced over about a 5 to 8 year period, along with train and tram service upgrades. The bus component of this transformed network would alone increase usage by more than the Suburban Rail Loop would while also being an essential feeder to it. 

2036 modelling

Improved bus services would encourage more people to use them, especially during off-peak periods. But would other transport modes that the buses feed cope? This is what the 2021 ATRF paper The impact of bus network reform on the resilience of Melbourne’s public transport system by Dr Ian Woodcock and Dr Jan Scheurer sought to answer. 

This work considers how things might be in 2036. It (optimistically?) assumes various rail project including Melbourne Metro 1, Airport and Melton electrified rail, Doncaster and Rowville rail, Metro 2 and Suburban Rail Loop East to be operational by 2036. Metropolitan train and trams frequencies would mostly be upgraded to 10 minutes where not already so. Also included is the DoT's Principal Public Transport Network (PPTN) which is basically an expanded SmartBus system. 

In the absence of specific network proposals in last year's Victoria's Bus Plan, I am honoured that they chose my 2021 Useful Bus Network (UBN) as a test component in two further scenarios. It was noted that "The UBN generally conforms to the principles of good network planning..." including a network hierarchy, simplicity, good interchanges and multi directionality. Furthermore, it would "place about 70% of Melbourne’s residents and jobs within walking distance of a public transport service of this standard or better, up from just over 56% in the base scenario for 2036 (and up from 51% in 2016)."

In other words we're talking about an accessibility uplift involving over a million people and jobs. Which makes the UBN a big deal (and the Future Frequent Network, which incorporates the UBN every 20 min plus a 963km long 10 min frequent network) an even bigger one. 

Woodcock and Scheurer's work says some interesting things about the Useful Bus Network and its impact. Much of this knowledge was gained through use of SNAMUTS tool for analysing transport networks. Key points include: 

1. Adding the Useful Bus Network would increase service intensity per 100 000 people but not unreasonably so. The base case cites 14.5 vehicles per 100 000 people compared to 13.4 in 2016. The base case plus the UBN increases this to 18.8. This is comparable to Adelaide in 2016 (18.4) and much less than some European cities (around 25). The Melbourne figure would rise to 19.7 if rail frequencies are boosted further to address expected crowding. 

2. Even though adding the UBN would not increase service to extravagant levels (note the Adelaide comparison above), it would deliver a coverage 'unprecedented' amongst New World Cities at 70%. On this metric we would beat both Vancouver and Sydney. This demonstrates the high potential of bus network reform to extend access to useful service. 

3. A UBN increases the share of travel opportunities captured by the bus system. This is described as 'modest' even though, looked at another way, a 10.5 to 13.4% increase is substantial. This share would be at the expense of tram, although this is mostly a relative drop. Rail's share would rise by 1%, largely due to the much increased catchment provided by the upgraded buses. Big increases in interchange would occur at key stations on the Sunshine - Dandenong (Metro Tunnel) rail axis. The availability of circumferential buses would also relieve pressure on radial trams across the inner north and east. 

4. Can a public transport initiative be too successful? Apparently the UBN is so good that it could be. Increasing access to rail also increases its likely usage to the point of overloading. This can cause the  rail network to be less resilient (UBN Scenario 1). Some of this is clawed back in the rail service increases contained in UBN Scenario 2 due to its upgraded 5 min train frequencies. Some feeder bus services in busy middle suburban and outer growth areas would also be taxed to the point of needing higher capacity with specific routes nominated. 

5. It is worth noting that some bus corridors to come under stress either do not or hardly exist today. Examples include Yarra Flats - Camberwell - Caulfield, Northland - Fairfield and the straightened 902 orbital between Keon Park and Doncaster via Greensborough. These are examples of high-demand bus routes that should be there but do not or only exist in amputated or infrequent form. Those advocating for a Burke Rd tram extension south to Caulfield and north to the Heidelberg area may get some satisfaction from this analysis pointing to likely heavy use. 

Conclusion

The paper shows the power of a modern bus network designed around sound principles like the Useful Network. However it points out that it can put pressure on the rail network (while relieving pressure on trams). Further rail network frequency and capacity improvements would be needed in some cases to maintain network resilience. 

Are these reasons not to introduce a basic upgraded bus network like the Useful Bus Network or a better version like the Future Frequent Network? I would argue not. 

After all these risks have not stopped other initiatives of lesser merit, such as cheaper (or free) fares or expanded parking at popular train stations in built up areas. The same goes with freeways which are often built piecemeal fashion. Those who commission them know full well that they will induce traffic onto other parts of the road network. Yet they build nevertheless, with the resulting congestion being used to strengthen the business case for the next stage of their project or related add-ons. Could transit system builders learn from this too, after all it's often only after times of network stress that there's been political pressure to upgrade infrastructure or services?

With  the COVID shock and what appears to be enduring acceptance of working at home for at least some days of the week, stresses on the rail network may be less than envisaged. The possibility of stagnant or at least slower growing rail usage has already been used in arguments against the Suburban Rail Loop which the Coalition has just said will shelve should they win office.  

Professional concern might have swung back from how to manage rail crowding to getting passengers to return. If this is the case then better buses, along with benefits in their own right, could be key to reviving rail usage. This analysis has demonstrated their power in doing just that. 

See other Building Melbourne's Useful Network items here