Western Railroad Discussion > America's Steepest Light Rail Line?

It is my understanding, but I cannot verify the claim that Utah Transit Authority's University Medical Center Light Rail Line in Salt Lake City is the steepest LRT route in America.

The University Line, built in two stages, climbs approximately 650 feet in elevation over a distance of 3.8 miles. The steepest portion of the U line can be found between the 900 East and Stadium stations along on an s-curve that UTA folks call "the incline."

The University Line was constructed in two stages. The original 2.3 mile line from Main Street in downtown Salt Lake City to Rice Stadium opened in time for the 2002 Olympic Winter Games on December 15, 2001, and the 1.5 mile University Medical Center extension opened for service on September 29, 2003. The 3.8 miles of track cost a combined total of $208 million. The University Medical Center extension opened 15 months ahead of schedule and under budget. Nearly the entire 3.8 mile distance was constructed up the middle of existing city streets.

In this photo, UTA TRAX University train #41 approaches Fort Douglas station on the corner of Campus Drive and Wasatch Drive. On the opposite side of the valley are the Oquirrh Mountains, home to the Kennocott Copper mine. UP's ex-D&RGW Roper Yard and the interchange of I-15 and I-80 are at center, in the middle of the Salt Lake Valley.

James

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I thought SF Muni's J- Church line was.

This looks like a bit of symantics. The original entry in this thread cites a total elevation change not a grade or graidient. So both could be accurate statements. I have some resources to tap ao I may have a future clarification or expansion.

Don't SF's Cable Cars qualify as light rail? That'd be the steepest hands down wouldn't it?

How about Calgary's Light Rail hike up the mountain to the University Station? It's a very steep climb...

tmengineman Wrote:
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> Don't SF's Cable Cars qualify as light rail?
> That'd be the steepest hands down wouldn't it?


No way. They were invented before someone coined the term "light rail".

SF's cable cars, as the name implies, are powered by an underground cable that the car grips and that drags it along uphill and keeps it under control downhill. They do not rely on steel-on-steel friction either to move the car uphill or to brake it going downhill. Given the grades involved, that reliance would fail immediately--the cars would slide backwards going uphill and would slide at increasing speeds going downhill (if the grip loses the cable going downhill the car is likely to run away even with the brakes fully applied, requiring the use of an emergency device that jams into the gap in the middle rail where the grip reaches for the cable). I think the question involves the steepest true steel-on-steel light rail grade. That would also exclude cog or rack systems of the sort invented for the Mt. Washington railroad and used at Pike's Peak and on several Swiss (and possibly other European) interurban lines. I do have the impression, from looking at the MAX lines in Portland, that light rail (or streetcars for the old fashioned) can handle steeper grades than can regular railroads. I suspect that that comes from every axle being powered and light rail having more power per ton, both things increasing adhesion and tractive effort, but that's just a suspicion.

This equates to 3.2% 3.8 miles = approx 20000 feet/650 rise.

Espee 99

The question as to which can "handle" a steeper grade boils down to pulling your own weight vs. pulling a train.

Friction, or adhesion rules here. The maximum tractive effort that can be applied to the rails is the weight of the motive unit time the frictional factor. One for one a locomotive should be able to climb a steeper grade than a light rail vehicle because its is heavier than the light rail vehicle, but a light rail vehicle only has to pull its own weight (and its onboard load), but for a locomotive to be useful it must pull a train. The train adds load to be moved but supports itself and does not add weight to the tractive wheels (drivers). Therefore grades on railroads are held to low limits to permit the locomotive(s) to be productive.

As a side note, the reason that "Trackmobiles" and similar vehicles can be effective is because their couplers are equipted with a lifting device. It is used to "pick-up" the coupler of the connected car thus transfering some of that cars weight to the wheels of the Trackmobile, giving it greater adhesion.

I am sure someone out there knows this, but the Fineview line in Pittsburgh (which ran until the 60s) had a bit of 12%, I believe.

Rule G - what is the gradient in the transit tunnel?

I was involved in all three of the phases of the UTA TRAX LRT Line (North/South, University Line, Medical Center Extension), and the maximum grade on the lines is 7% in the area surrounding the S-curve transition from 400 South to 500 South, just west of the U of Utah. There are other lines that have similar grades, Baltimore has 6%+, I believe, Pittsburgh's got some real doozy's too, but I don't have the percentages on those.

Do not forget the Skiskyou line near Black Butte.. 4 percent at the summit speed limit aproaching is 5 mph both directions!

While we're at it, what candidates from the past?

San Francisco's #35 streetcar had a short block of 15.5%, on 24th up to the end of the line at Rhode Island. Ended 1939.

Oakland/Piedmont had 13.5 to 14% on Oakland Ave, and one block on Euclid in Berkeley was about the same.

timz Wrote:
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> >
> Oakland/Piedmont had 13.5 to 14% on Oakland Ave,
> and one block on Euclid in Berkeley was about the
> same.

At one point, there was cable car on Oakland Ave. I lived there when the street got a major upgrade, and the contractor was very surprised to find a concrete cable box below grade. They lost a ton of money.

It seems that new Light Rail systems will not capture the steepest grade contest. Present day vehicle manufacturers generally promote their light rail vehicles as being capable of 6% grades as an all-weather maximum. System operators frequently require lesser grades do to limitations of their maintenance-of-way "Hi-Rail" equipment. It seems that most of this equipment uses rubber tire on rail for motive power and braking, and that just is not as effective as steel on steel.

Ron Zimmer

Utah may be the HIGHEST line, but not the steepest.

CivilEngineer Wrote:
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> I am sure someone out there knows this, but the Fineview line in Pittsburgh (which ran until the 60s) had a bit of 12%, I believe.
>
> Rule G - what is the gradient in the transit tunnel?


The Pittsburgh Brown Line has 10 percent grades:

https://en.m.wikipedia.org/wiki/Brown_Line_(Pittsburgh)

It's in use now just about every night so that work can be done in the Mount Washington tunnel.

Brian