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Ottawa Transit Developments
- Thread starter Reecemartin
- Start date
SaugeenJunction
Senior Member
Love me a good POV line ride.
rhys17
New Member
Bojaxs
Active Member
What an absolute disaster. If Alstom's accusations are correct, to think that perhaps the tracks were not planned and laid down properly, curves too tight, etc. What a major oversight by the supposed "rail experts".
Ottawa will be stuck with slow LRTs for the foreseeable future until something major is done. People will opt to drive or take the bus if the LRT doesn't speed up.
drum118
Superstar
I guess they will shipped the first Hurontario LRV that been in Kingston since last year to test the various changes for the Ottawa LRV's since they are the same to the OMSF now. I guess the rest of the fleet will now be built even though there is no OS in place for them at this time.
Tracks and poles will be in place to Eglinton in place of Matheson by July. As when the OS will be stun, who knows and may see testing and burn-in start by year end considering it was to happen in Feb this year to Matheson.
CapitalSeven
Senior Member
I've beaten the "tight curves" fallacy pretty hard already but it won't die. Virtually all modern light rail vehicles carry a stated minimum curve radius of 25 meters / 82 feet. The Citadis Spirit is no exception.
Here is a snip from an old Alstom Brochure for it:
Here is an image from Google Earth with the circle measuring tool of the tightest curve on the revenue portion of the Ottawa line, east of Hurdman.
I'm not sure how Alstom could argue that four times minimum is too tight, or why people keep saying the line might have to be rebuilt.
I put together a collection of "tightest curves" on modern LRT systems I have ridden in the past. It doesn't include networks based on legacy tram and streetcar systems like Toronto, Boston, and San Francisco, which often had much tighter turns.
Calgary, at 9th:
Los Angeles, near Union Station:
Sydney, near Central:
Denver, at Aurora:
San Diego, near Amtrak Depot. Love this one, all those impossible curves. Designed on a Spirograph?
Portland, near stadium:
And, gratuitously, Chicago, the Loop. Remember the Loop, where trains have gone around at least four 90-foot turns per trip for over a hundred years? OK, it's a legacy system, but it's a legacy heavy rail, not light rail, system. Of course the distinction is not always clear. But at 110 metres, Ottawa's tightest, impossible-est curve is more than four times looser than the sharpest turn on several other systems that have been operating for years. It is about the same as the Union to King curve in Toronto, which heavy rail cars have screeched around since the 1950s.
Whether Ottawa's problem is the vehicles (wheels, bearings, etc.) or the rails (profile, gauge, hardness) remains to be seen. Alstom is supposed to address the city today with its latest, probably self-serving, explanation. But tight curves™ is not aleg they have to stand wheel they have to roll on on.
Here is a snip from an old Alstom Brochure for it:
Here is an image from Google Earth with the circle measuring tool of the tightest curve on the revenue portion of the Ottawa line, east of Hurdman.
I'm not sure how Alstom could argue that four times minimum is too tight, or why people keep saying the line might have to be rebuilt.
I put together a collection of "tightest curves" on modern LRT systems I have ridden in the past. It doesn't include networks based on legacy tram and streetcar systems like Toronto, Boston, and San Francisco, which often had much tighter turns.
Calgary, at 9th:
Los Angeles, near Union Station:
Sydney, near Central:
Denver, at Aurora:
San Diego, near Amtrak Depot. Love this one, all those impossible curves. Designed on a Spirograph?
Portland, near stadium:
And, gratuitously, Chicago, the Loop. Remember the Loop, where trains have gone around at least four 90-foot turns per trip for over a hundred years? OK, it's a legacy system, but it's a legacy heavy rail, not light rail, system. Of course the distinction is not always clear. But at 110 metres, Ottawa's tightest, impossible-est curve is more than four times looser than the sharpest turn on several other systems that have been operating for years. It is about the same as the Union to King curve in Toronto, which heavy rail cars have screeched around since the 1950s.
Whether Ottawa's problem is the vehicles (wheels, bearings, etc.) or the rails (profile, gauge, hardness) remains to be seen. Alstom is supposed to address the city today with its latest, probably self-serving, explanation. But tight curves™ is not a
dowlingm
Senior Member
What’s the vertical elevation on that curve - is there a significant change over the length of it?
smallspy
Senior Member
I don't think that they are specifically referring to the curves being too tight per se.
But rather that the curves are too tight for the speeds and type of service that are being asked of them.
Most of the curves that you've mapped out are in urban areas, and frequently as a part of a junction or turning from street-to-street. While there are a couple of areas like that in Ottawa, most of curves on the mainline aren't, and could have been designed to be wider should they had felt the need to. The three curves around Hurdman are a prime example of that.
Dan
reaperexpress
Senior Member
But even with 110m curves, the current 25 km/h speed limit is surprisingly slow. For example CLRVs and ALRVs used to take the curve at Bathurst & Queens Quay at 15 km/h and that's only a 20m radius. It would be interesting to hear what the speed limits are around those other curves that @CapitalSeven measured. Or even better, find some 110m radius curves on other systems and see what their speed limits are (e.g. by checking signs via streetview or cab ride videos)
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CapitalSeven
Senior Member
Those are valid points.
Most of the Hurdman curves are fairly level but the one across the river has a bit of a slope to it, as does the tunnel southeast of Rideau. Maybe the track was not correctly banked in these areas? Dunno.
One of the reasons for opting for light rail in Ottawa was to reuse as much of the existing corridor as possible, which could be done with curves four to five times as wide as the rated minimums for the vehicles. So the route was a reasonable choice, although as stated some of the curves could be flattened out. The VIA curve to the right below is about 235 meters. Does the LRT really have to be built to the same stadard to work correctly?
However it's not as if Ottawa has the only wobbly LRT route.
Seattle:
San Diego (same spot as earlier post):
LA, bigger chunk of the section south of Union:
My argument is that while 25-meter curves are a sort of necessary evil in downtowns in order to follow street grids,* the 110- to 120-meter curves in Ottawa are well within the capabilities of light rail to run at medium speeds. Except it currently doesn't work because of engineering flaws in the vehicles, tracks or both. The companies did not make much profit because the contract was pretty cheap, and now they are pointing the finger of blame at each other and the route, when it seems clear to me that they just didn't work effectively together and/or separately to create a functional, whole system at the technical level.
Ottawa is now so afraid of curves that they redesigned the hopelessly expensive Barrhaven extension so that the S-curves on Woodroffe would be no tighter than 650 meters, which is approximately the minimum for the Havelock Subdivision, on which VIA proposes to build higher-speed intercity express rail. Ottawans have been led to believe the Confederation line is some sort of impossible spaghetti corkscrew no vehicle could negotiate. I saw a forum poster ask whether any light rail system has vehicles that could handle the curves. The answer is that they all (and many heavy rail systems) do. And recently another lamented that Ottawa doesn't have the Toronto LRVs that have a tighter turning radius, which they don't, at all.
*Probably not in Ontario, since the old towns were laid out with narrow, parsimonious streets that have a nice feel for pedestrians but have made surface transit difficult post WWII.
Most of the Hurdman curves are fairly level but the one across the river has a bit of a slope to it, as does the tunnel southeast of Rideau. Maybe the track was not correctly banked in these areas? Dunno.
One of the reasons for opting for light rail in Ottawa was to reuse as much of the existing corridor as possible, which could be done with curves four to five times as wide as the rated minimums for the vehicles. So the route was a reasonable choice, although as stated some of the curves could be flattened out. The VIA curve to the right below is about 235 meters. Does the LRT really have to be built to the same stadard to work correctly?
However it's not as if Ottawa has the only wobbly LRT route.
Seattle:
San Diego (same spot as earlier post):
LA, bigger chunk of the section south of Union:
My argument is that while 25-meter curves are a sort of necessary evil in downtowns in order to follow street grids,* the 110- to 120-meter curves in Ottawa are well within the capabilities of light rail to run at medium speeds. Except it currently doesn't work because of engineering flaws in the vehicles, tracks or both. The companies did not make much profit because the contract was pretty cheap, and now they are pointing the finger of blame at each other and the route, when it seems clear to me that they just didn't work effectively together and/or separately to create a functional, whole system at the technical level.
Ottawa is now so afraid of curves that they redesigned the hopelessly expensive Barrhaven extension so that the S-curves on Woodroffe would be no tighter than 650 meters, which is approximately the minimum for the Havelock Subdivision, on which VIA proposes to build higher-speed intercity express rail. Ottawans have been led to believe the Confederation line is some sort of impossible spaghetti corkscrew no vehicle could negotiate. I saw a forum poster ask whether any light rail system has vehicles that could handle the curves. The answer is that they all (and many heavy rail systems) do. And recently another lamented that Ottawa doesn't have the Toronto LRVs that have a tighter turning radius, which they don't, at all.
*Probably not in Ontario, since the old towns were laid out with narrow, parsimonious streets that have a nice feel for pedestrians but have made surface transit difficult post WWII.
reaperexpress
Senior Member
The curve halfway between Hurdman and Tremblay stations (the one that constrains speeds the most since it's furthest from a station) is actually far tighter than the curve on the Transitway was.
I found a Los Angeles A Line cab ride video where you can see the speed limits in miles per hour on the cab display, so I can report that this 37m curve has a 15 mph (24 km/h) speed limit. That's the same speed as Ottawa's 110m curves.
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Kyle Campbell
Active Member
OC Transpo has some virtual tours of a few stations and the trains for Lines 2 and 4 up now
www.octranspo.com
Virtual tours | OC Transpo
www.octranspo.com