BC Ferries explains why they have changed how vessel capacity is measured

In response to our Quinsam Shrinks article,  BC Ferries has offered clarification on some of the questions asked. Here’s what Mark Collins, Vice President (Strategic Planning and Community Engagement) had to say in response to our statements:

FAC: The AEQ is a measure of deck space which was deemed to be the equivalent of one car length. The value of this calculation was that it enables BC Ferries to report accurately on what percentage of each route’s vehicle capacity was actually being used.

BCF: In fact the calculation you refer as “…accurately…” had a flaw.  With this change we have corrected it.  

FAC: Cars have got smaller over the years and it’s not at all unusual for Quinsam to carry 75 or more vehicles on busier sailings

BCF: We don’t have any data which suggests the average car size has gotten smaller.  Our information suggests the opposite, that the average size of vehicles has grown. 

FAC: Quinsam’s capacity has dropped from 70 AEQ’s to just 63.

BCF: Sorry but this is not an accurate statement.  The Quinsam’s capacity did not change; the deck area is exactly the same before and after the change.  All that has changed is the unit of measure of deck area.  Rather like measuring a house today in sq ft and tomorrow in sq meters, the house is still the same size. There is no intention to reduce numbers allowed on board.  Nothing has changed except how the area of the deck is measured.

FAC: An AEQ has been recalculated as 6.1 metres (20 feet) – which happens to be the maximum length of vehicle that can travel at the standard fare, but that’s where the logic seems to end.

BCF: 6.1 m AEQ is used in more places than just the standard fare determination.  In fact, the old 5.3m AEQ was a primary measure in a single place in our systems: the measurement of ship deck space.  There are many other places in our system that all use 6.1 m AEQ.  Terminal holding compounds for example, are measured with 6.1 m AEQ and have been for decades.  The old measure of deck space using 5.3m was the exception, not the rule. BCF should have fixed this years ago but didn’t because it didn’t want lose comparability with past data.  So we allowed two different measures of the same quantity/parameter to perpetuate.  

What about backwards comparability?  To allow backward comparability one or more previous years traffic data will be re-stated using 6.1m AEQ in our reports.  We will adjust other reports on an as needed basis.

 Why harmonize on the 6.1m AEQ and not the 5.3?   Since: (1) the majority of our systems are already based on 6.1m AEQ, and (2) since 6.1m is a more accurate reflection of the reality of today’s vehicles, harmonizing on the 6.1m AEQ required the fewest changes, least disruption and provided the greatest efficency gain.  It also gives is capacity numbers which most closely match customer’s experience.

FAC: Quinsam will continue to carry 75 or more vehicles at busy times, so the new measure seems, well, meaningless.

BCF: Meaningless to some maybe but not meaningless to us and certainly not to people who wish to see good ferry system performance.  In our view this more accurately reflects the proportion of space used since the 6.1m AEQ is closer to the average size vehicle we actually carry.  Most of our fleet routinely carries below the old stated AEQ capacity.  This changes beings our standard capacities more in line with reality, not further away.

FAC: What’s worse is that it now means vehicle utilization statistics reported to government are suddenly 10% higher than they were before. There’s an explanation that an AEQ is now longer, but no explanation why.  

BCF: we trust the “why” is now satisfactorily explained above.

FAC: To the casual observer (or as a message to a new government) it’s great news of course. Our ferry (which was targeted for cuts in 2013 because it only achieved 45% utilisation) has now averaged 58% over the past year – peaking at 66% in summer 2016.

BCF: We trust the above explanation makes clear the lack of foundation for the “message” insinuation.

FAC: Not really. Applying the formula used in 2013, it has increased from 45% to 52% in the past year – and this summer vehicle utilisation was up by 2% from last year to 59%, not 66%. Vehicle utilisation is increasing, but why change the formula now?

BCF: There is no good time to make a change of this type.  But it still had to be done to correct the issues above.  Why now?  (1) Accurate specifications were needed in Fall 2016 for the new Minor 44 vessel (as they will be for the many other new vessel and terminal projects coming), and (2) Accurate, realistic measures of deck space are required for the new point of sale and reservation systems we are presently building. Finally, the measure is not a vehicle limit.  It is measure of standard capacity. 

Chair’s comment –

I’m grateful to BC Ferries for supplying this explanation.

So it seems the new measure is here to stay. It does not affect the number of vehicles carried – and, in the eyes of BC Ferries at least, it more accurately represents reality, as well as providing solace to “people who wish to see good ferry system performance” (presumably meaning  government).

But, as a formula, does the new methodology really give a more accurate reflection of capacity utilisation?  I’m not so sure. A ferry with 70 cars on it used to be recorded as full. Now, with a notional capacity of 63, 7 of the cars on that ferry will be counted as “over capacity”. The daily total may not change, but it must surely distort the reported utilisation measure?

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