North Downs Line - making request stops

[hkstudent]

When looking at the calling pattern of North Downs Line, it often finding many stations like Gomshall are only having 1 train per 2 hour.

It appears to be too infrequent for a line that is served by 2 trains per hour. Would it be better off to make those infrequent stops be request stops and be better demand matching?

 

[30907]

Looking at the timetable, each stop costs about 2min. Making them request stops would save 1/2min per stop per GB timetabling conventions, so you would barely be able to squeeze one extra stop in, not 2. (I am assuming that Shalford, Deepdale and Reigate would not be request stops.)

I leave it to others with much more recent local knowledge to comment on potential offpeak demand.

 

[simonw]

Looking at the timetable, each stop costs about 2min. Making them request stops would save 1/2min per stop per GB timetabling conventions, so you would barely be able to squeeze one extra stop in, not 2. (I am assuming that Shalford, Deepdale and Reigate would not be request stops.)

I leave it to others with much more recent local knowledge to comment on potential offpeak demand.

I think the op is suggesting allowing a customer to request a train, not currently scheduled to stop, to stop in addition to the 1 stop every two hours, not to make them all request stops.

 

[30907]

I think the op is suggesting allowing a customer to request a train, not currently scheduled to stop, to stop in addition to the 1 stop every two hours, not to make them all request stops.

In which case you need to add 1.5min to each journey to allow for the potential stop, and that's impossible with the constraints on the timetable.

 

[devon_belle]

I would propose instead to increase the frequency of calls to those stations. They have comparable usage to the Dorking-Horsham stations which benefit from a 1tph (albeit 5.5 days per week) electrostar service to/from London Victoria.

I'm not sure why those stations are 1tp2h, but there usually seem to be people getting on/off at the small stations between Dorking Deepdene and Shalford. I can't speak for Betchworth because I rarely get the train in that direction. Dorking West is an interesting one because it is the accessible alternative to Deepdene, although the pedestrian journey between the two is not the shortest or flattest. Additionally, tickets are often sold to 'Dorking Stations' so actual usage figures are hard to decipher.

I guess that when new trains with better acceleration come in every station will get at least 1tph, but I'm not sure if signalling changes would also be needed to achieve that and the coveted third train per hour. Gomshall should be the focus of any increase in service frequency in my view, as it is the busiest of the shacks and has lots of nature/walking appeal like Boxhill and Westhumble.

 

[zwk500]

In which case you need to add 1.5min to each journey to allow for the potential stop, and that's impossible with the constraints on the timetable.

1.5 min is a good approximation, although technically it can be more or slightly less depending on the SRTs.

I think the op is suggesting allowing a customer to request a train, not currently scheduled to stop, to stop in addition to the 1 stop every two hours, not to make them all request stops.

Request stops are timed as a zero-dwell stop (also known as a 'dot stop') with an additional 30 seconds runtime after the request stop to allow for if the train needs to stop. This means that compared to a booked stop, you are only saving the Dwell time minus 30 seconds. If the dwell time at the station would be 30 seconds, then there is no timetable benefit to it being a request stop, only a potential performance benefit (offset by the potential to run early and be held at signals later).

 

[Recessio]

Very anecdotal experience suggests a fair chunk of the traffic at Dorking Deepdene is school traffic. It would be interesting to know if the usage patterns at the other stations is constant or if it spikes throughout the day - would going from 1tp2h to 1tph be justified throughout the day? Or would it be better to have more stopping services in the morning and evening peaks but keep 1tp2h in the off peak.

Regardless I've never been a huge fan of request stops. You effectively have to timetable a stopping service just in case all the stations get stopped at anyway. So either just have a stop scheduled or don't.

 

[devon_belle]

Very anecdotal experience suggests a fair chunk of the traffic at Dorking Deepdene is school traffic.

In mine it is a decent amount of airport traffic and a lot of commuting/leisure between Guildford-Dorking-Redhill. I've rarely found the trains to be overloaded or empty, having travelled at quite a few times of day for various reasons.

Or would it be better to have more stopping services in the morning and evening peaks but keep 1tp2h in the off peak.

I believe they are already 1tph in the peaks. Certainly in the morning.

Regardless I've never been a huge fan of request stops. You effectively have to timetable a stopping service just in case all the stations get stopped at anyway. So either just have a stop scheduled or don't.

Agree.

 

[izvor]

I do wonder if some lines with a series of lightly-used stations (not necessarily the NDL) should make them request in the evenings, e.g. after 2000 or 2100. If it were considered unlikely that stops would be required at more than, say, 2 out of 5 then it might enable more stations to be served, as well as eliminating unnecessary stops.

 

[JonathanH]

I'm not sure why those stations are 1tp2h

It is a legacy of the stopping service having been scaled back in the 1980s. For a long time, essentially the equivalent of one unit was used to provide the off-peak stopping service east of Guildford.

It is a really difficult position to increase the services at Chilworth, Gomshall, Dorking West and Betchworth. They simply can't justify their own stopping service if taken out of the Gatwick trains.

I guess that when new trains with better acceleration come in every station will get at least 1tph, but I'm not sure if signalling changes would also be needed to achieve that and the coveted third train per hour.

The service is currently the best compromise available with seven units. 2tph at Wokingham, Blackwater, North Camp, Guildford, Dorking Deepdene, Reigate and Redhill, 1tph at Crowthorne, Sandhurst, Farnborough North, Ash and Shalford, 1tp2h at Chilworth, Gomshall, Dorking West and Betchworth. Even with better acceleration, is the priority more stops at the local stations or better journey times to Gatwick.

If it was desired to get 1tph at the four stations, I reckon that it would probably be desirable to have 3tph north of Guildford only, with then the local stops across the two trains that run through to Gatwick. However, that could well need nine units which is a considerable uplift in operational costs relative to now.

 

[Farigiraf]

Regardless I've never been a huge fan of request stops. You effectively have to timetable a stopping service just in case all the stations get stopped at anyway. So either just have a stop scheduled or don't.

They're a good idea for lines with lots of intermediate small stations which are skipped most of the time but do still provide an important benefit to the places they serve. It saves a bit of energy each time you skip one so it pays off after enough time, alternatively you could install some buttons to improve the passenger experience and reap the benefits through ridership growth and passenger satisfaction instead. On these kinds of lines speed is not the biggest priority, it's the train turning up at all, so the timetable padding required to accommodate these potential stops is not a huge inconvenience.

The issue is that we closed nearly all of these in the last hundred years.

Very anecdotal experience suggests a fair chunk of the traffic at Dorking Deepdene is school traffic. It would be interesting to know if the usage patterns at the other stations is constant or if it spikes throughout the day - would going from 1tp2h to 1tph be justified throughout the day? Or would it be better to have more stopping services in the morning and evening peaks but keep 1tp2h in the off peak.

I reckon that even without direct services to London, the North Downs line is useful enough that every station on the line can do with 1tph all day. If it doesn't ruin the timetable then yes it may be worth trialling a doubling of services only at peak times, but the benefit of having a predictable all-day (reliable) train service is that it starts being used by a lot more people for more reasons than just commuting, making it a useful transport hub for the town/village it serves, not just a peak-time traffic bypass combined with an off-peak safety net service for those who don't drive.

I reckon most would still park&ride at a mainline station for accessing London, but Reading, Guildford and Gatwick Airport still make for a great trio of connection options, as you can access many parts of the country (and other countries) from these destinations. If it would significantly increase usage then I may be wrong, but I think adding the proposed third hourly train on the line (with a faster stopping pattern) would be overall less useful compared to accepting that it's a regional connector (not an airport express) and giving most stations on the line a decent service. May cost end-to-end passengers (who are usually making less time sensitive trips) 10-20 mins but it saves other passengers 1-2 hours. It's quite a successful line already, all things considered (slow, unelectrified, non-London, low priority), so it deserves some investment anyway in recognition of that.

 

[zwk500]

I do wonder if some lines with a series of lightly-used stations (not necessarily the NDL) should make them request in the evenings, e.g. after 2000 or 2100. If it were considered unlikely that stops would be required at more than, say, 2 out of 5 then it might enable more stations to be served, as well as eliminating unnecessary stops.

As mentioned in post #6, there is minimal timetable benefit to making stops request stops.

 

[izvor]

I reckon that even without direct services to London, the North Downs line is useful enough that every station on the line can do with 1tph all day.

I'd argue that, of the 4 stations mentioned above, only Gomshall might justify increasing to 1tph all day. But, M-F, there's only a few hours when it's less than that anyway.

I think adding the proposed third hourly train on the line (with a faster stopping pattern) would be overall less useful compared to accepting that it's a regional connector (not an airport express) and giving most stations on the line a decent service. May cost end-to-end passengers (who are usually making less time sensitive trips) 10-20 mins but it saves other passengers 1-2 hours. It's quite a successful line already, all things considered (slow, unelectrified, non-London, low priority), so it deserves some investment anyway in recognition of that.

It's Gatwick that has mainly made the line successful, plus development in the Blackwater Valley. End-to-end journey times are important for this market, and the perception must be that this is slow enough as it is.

It is a really difficult position to increase the services at Chilworth, Gomshall, Dorking West and Betchworth. They simply can't justify their own stopping service if taken out of the Gatwick trains.

The service is currently the best compromise available with seven units

If it was desired to get 1tph at the four stations, I reckon that it would probably be desirable to have 3tph north of Guildford only

All valid points. Plus the level crossing issue at Reigate, a problem arising with any increase to 3tph; and the fact that GWR struggle to run the existing service as it is. All mentioned in earlier threads on this line.

As mentioned in post #6, there is minimal timetable benefit to making stops request stops.

I saw this, and agree. My idea was more to make better use of available time.