Night Tube on the Central Line

Please could provide the detailed analysis undertaken for the decision taken to exclude the Northolt Station branch of the Central Line from 24 hr service at weekends.

The Ealing Branch is already served by night buses, mainline rail and the surrounding area by the Piccadilly Line. Excluding the North West London area from the benefits of 24 hr travel feels discriminatory and it would be helpful to understand why this is not the case. insert quote here

TfL has undertaken analysis of night bus routes that are within close proximity of the proposed Night Tube.

We developed a bespoke demand forecasting model, to look at the diversion of trips from bus routes to parallel Underground routes. An assessment of the level of likely trip diversion was made, and it was determined that passenger numbers shifting from night bus to Tube will likely be between 5 per cent and 85 per cent. The Night Tube will never divert 100 per cent of night bus passengers as 4 some customers have a strong modal preference for bus, based on stop location, lower fares, and other reasons.

There are some parts of the Underground network with no parallel overnight bus routes or bus routes with similar key origins/destinations. This includes the West Ruislip branch of the Central line, where existing night bus routes, and therefore existing demand for travel, are generally North/South rather than East/West. This means that there is a very low demand identified in the Night Tube demand forecasting model. There is a similar occurrence north of Woodford, and between Woodford and Hainault, on the Central line, east of Barking on the District line, and north of Harrow-on-the-Hill on the Metropolitan line. There is a low level of existing demand on buses which partly parallel the Bakerloo line too, which means the Bakerloo line is not in the initial Night Tube plan.

After establishing a base level of demand, some further refinements were made to ensure the network serves the maximum number of customers and is operationally robust. These evolved into basic ‘rules’ for the initial Night Tube network:

1. Provide a simple end to end service

2. Provide a minimum of four trains per hour

3. Routes operated to broadly reflect the current night bus network

4. Routes and termini should match those of existing night buses, to reduce the requirement for customers to have to interchange to reach their destination;

5. Each line should serve at least one train depot to facilitate swapping of trains if required; and

6. Options will be considered particularly where additional service could be provided for zero or minimal additional staff resource and cost

With the methodology developed above based on existing public transport trip patterns, we are simply not confident at this initial stage that there will be sufficient demand between North Acton and West Ruislip to justify operation of this section of the Central line as part of Night Tube. However, we’ll keep it under review and would hope to extend Night Tube in future – in particular, once the improvement programme on the Circle, District, Hammersmith & City and Metropolitan lines is complete, we will look at introducing Night Tube on the parts of those lines where there is known to be a night time demand. Any Night Tube service on those four lines would not be introduced before 2019. However, if customer demand and travel patterns suggest that we need to make changes to the initial network before then, we will do so.

1. Does the forecasting model have any built in safeguards to avoid a catch-22 scenario whereby no current bus parallel would result in area being excluded regardless of potential usage?

2. Was the route N7 included in the modeling?

There are some examples where a station is served by a night bus that could be argued to broadly parallel an Underground line, that is not included in the initial Night Tube service. This is because there needs to be a critical mass of ridership/potential ridership to enable cost-neutral operation of trains.  A single station such as Northolt does not, initially, justify this. However, it is important to remember that Underground timetables are continually being revised, and we expect the Night Tube service to evolve over time, both in terms of frequency and the extent of the network, just as the overnight bus network has done. 

I can confirm that the N7 was included in the modelling. The routes assessed were as follows

24 Northern  
25 Central District
69 DLR  
72 Hammersmith & City
83 Northern Piccadilly
88 Northern Victoria
93 District  
94 Central  
139 Jubilee  
188 Bakerloo Jubilee
205 Hammersmith & City District
220 Hammersmith & City
295 Hammersmith & City
297 Jubilee  
C2 Northern  
N2 Victoria  
N5 Northern  
N7 Central  
N8 Central Hammersmith & City
N9 District Piccadilly
N10 Piccadilly  
N11 Piccadilly  
N13 Metropolitan
N15 District  
N16 Northern  
N18 Piccadilly  
N20 Northern  
N22 District  
N29 Piccadilly Victoria
N47 Jubilee  
N55 Central  
N73 Victoria  
N91 Piccadilly  
N98 Jubilee  
N113 Metropolitan
N149 Victoria  
N207 Central Piccadilly
N253 Northern  
N279 Northern  
N381 Jubilee  
N550 Jubilee  
N551 Jubilee  
N155 Northern Victoria