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Originally Posted by MalcolmTucker
Stations with large amounts of boardings and alightings will have longer dwell times than those without. Trying to do boardings onto what will remain the busiest part of the system is a bad idea because the increase in dwell time due to increase of demand like most things in transportation in a U shaped curve, above a certain capacity factor, increase in use will decrease passenger throughput per LRV instead of increasing it due to congestion.
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Yes, dwell times that are affected by both alighting and boarding. The scenario you are saying would be problematic is largely affected only by potential boardings, and not alightings, thus already resulting in a non-critical dwell time comparitively. If the trains really were that full, people simply wouldn't try to get on them and simply go to the next transfer station. As said, this could be influenced by scheduling the SELRT to come immediately after the SLRT departs this "proposed" east transfer station. At a 2 min headway, this may not have much effect, but at a 5 min one, and with timed transfers scheduled from a NLRT going south at the 8th ave transfer station would make that then a viable option.
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To avoid this problem one would have to increase capacity by a fair bit on the south line, an investment that otherwise wouldn't be needed. Since our system is not meeting even current demands for capacity, I doubt we would ever add enough to make this extra transfer impose minimal costs.
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However, if the above (my first paragraph) is then a 2 min headway as CTs goal is, and with 4 car TUs then capacity should no longer be an issue. It is also important to note that a certain percentage of current SLRT riders may change their route to that of the new SELRT.
So I'm not sure how it can be said that it is doubtful if that is already the goal anyway.
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I am not saying that under conditions where there is enough capacity the transfer would be bad, I am just saying it is highly unlikely that a transfer of this sort would ever be backed up by enough extra capacity to not cause large indirect costs.
In either case, you are causing large ongoing costs to a large number of individuals and the system (in the case of not enough capacity), or large costs to the system (in the case of enough added capacity between downtown and the transfer).
I just don't think the potential benefits to SE --> South transfer and SE to east downtown transfers would add up to anywhere near the costs.
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Again, if both the SLRT and SELRT are in their dedicated tunnel, the average operating speed has already been increased. Assuming that indeed, there would be a larger station dwell time than were it not a transfer station (and thereby, that this is then also not an additional station in relation to what currently exists,) then overall travel time is still greater, and hence so to the potential for less TUs and thereby drivers (ie, cheaper operational costs.) Yes, on a ceteris paribus basis, without a station there or one that isn't a transfer station it is rather likely that travel times would be quicker, but as my first paragraph already states probably likely little.
I can agree that on the short term this cost to SLRT riders is not compensated on a socially optimum basis by an aggregated decreased travel time benefit from SELRT to SLRT south riders (tranferers.) However, this is leaving accessibility as a disregarded indicator (which is indeed hard to monatize, but important nonetheless,) as well as induced demand (because of increased accessibility and shorter travel times (that are in a realm of elastically significant,) that then has the potential to take vehicles of the road, urban generation, not etc.
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Not really - Calgary's LRT has for a long time focused on keeping operating costs low, as technology costs have gone down we are only recently embracing the innovations of air conditioning, fare machines that take plastic and give change, and real time arrival times.
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Yeah, operating costs of the Ctrain line. Doesn't matter that the bus lines, and well the city's operating costs in general don't coincide with this.
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If there were appreciable benefits to an east end transfer, I'm sure it will be recommended in the hopefully soon to be seen tunnel study.
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To say that economic analysis should be thrown to the wind is ludicrous - would you have spent more to serve less people by routing the West LRT to Mount Royal College? Would you maintain express buses to downtown from outlying communities because some will stop taking transit due to the transfer?
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I don't know where you got that I don't think an economic analysis is not necessary. Quite the opposite. I think, let's call it a Cost/Benefit, needs to go way beyond simply looking at that one line. I think I've made that clear above, and not only that, but it should go beyond simply monetizable indicators. I can't speak to what extend this is done for any of these lines, nor can I speak to the routing decision of the WLRT. That was an entirely new line and I don't know what kind of modelling was done to arrive at potential catchment areas and ridership, let alone what kind of resistance functions, OD matrix, etc, were used. I don't particularily think it is a good idea to make efficient transit go almost to the edge of the city boundaries due to induced suburbanization, but that is just one angle.
Indeed it is likely best that buses act as a feeder in this case. However, the situation being commented further above is taking a lot of this information for granted as the one route exists (SLRT) and the other is planned (SELRT.) I'm suggesting a piece of infrastructure to optimize it.
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The city has a limited budget for capital improvement, but that is almost entirely funded by outside grants, because operational costs are funded by local taxpayers and fares, there is a reason most investments are judged at least partially by their impact on operating costs.
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True enough. Additional capital costs are always (I say that confidently) foregone to inevitably lead to higher operational costs and not the other way around (and not just in Calgary's case.) This is exactly what I'm advocating. Higher capital costs for lower operational costs while serving more people optimally, especially in a long term, holistic, systems perspective.
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Or else we end up like Ottawa, which has a subsidy almost twice as large to serve less riders.
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Yup.
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