Average unit cost of installing light rail in street/arterial alignments

Left: Phoenix LRT in arterial alignment. Right: Houston LRT in street alignment. Photos: L. Henry.

Left: Phoenix LRT in arterial alignment. Right: Houston LRT in street alignment. Photos: L. Henry.

Increasingly, interest has been growing in the use of street and arterial roadway rights-of-way (ROW) as alignments for new light rail transit (LRT) segments – either new-start systems or extensions to existing systems. As planners, other professionals, advocates, and civic leaders consider such projects, it’s useful to have reliable data on the installation costs.

Unfortunately, many available “average unit cost” methodologies present averages based on various types of alignment — such as re-purposed railroad ROW – rather than exclusively or predominantly street/arterial corridors, which present quite specific needs, challenges, and costs with respect to installation of LRT. For example, while railroad ROWs typically need rehabilitation, much of the necessary preparation for LRT tracklaying is usually in place; space and installations costs for overhead contact system (OCS) infrastructure and stations are often easier to deal with. On the other hand, installing LRT tracks, stations, and electrical systems in streets/arterials typically requires extra (and more costly) tasks such as pavement removal, subsurface utilities relocation, traffic management and reconfiguration, and other measures.

The brief study described in this post has been undertaken as an effort toward fulfilling the need for reliable total-system unit cost data for street/arterial LRT project installations. It has focused on predominantly (or exclusively) street/arterial LRT projects, drawing upon data from eight specific projects in five U.S. cities (Salt Lake City, Houston, Portland, Phoenix, and Minneapolis) as listed in the table further below.

Also, this study (conducted by LRN technical consultant Lyndon Henry) has endeavored to avoid carelessness as to what is designated as “light rail”. As it has been most pervasively considered since the 1970s, LRT is regarded to be an electrically powered mode, not a light diesel-powered regional railway. For the purposes of this study, LRT has been considered as both electrically powered and operating predominantly in exclusive or reserved alignments (i.e., streetcar-type systems have been excluded).

Analysis of this data has yielded an average capital cost of $85.5 million per mile ($53.0 million per kilometer) for construction in these kinds of alignments. This figure might be considered appropriate for approximating system-level planning cost estimates for corridors considered possible candidates for LRT new starts or extensions. (Capital costs, of course, may vary significantly from corridor to corridor depending on specific conditions, infrastructure needs, service targets, and other factors.)

It should be noted that these data have been primarily drawn from Federal Transit Administration resources (particularly New Start profile reports), supplemented where necessary by data from Light Rail Now and Wikipedia. Because these figures present final total capital cost data, they represent final year-of-expenditure costs, including infrastructure and vehicle requirements, and incorporate other typical ancillary cost items such as administration, engineering, contingencies, etc.

Capital costs for the eight projects were tabulated as shown in the table below.


Relevant data for 8 LRT segments used in study. (Click to enlarge.)

Relevant data for 8 LRT segments used in study. (Click to enlarge.)


NOTES

Portland: Interstate (Yellow) line data include section at outer (northern) end on viaduct over Columbia Slough and flood plain. Phoenix: Initial project data include new LRT bridge over Salt River, and short section on abandoned Creamery Branch of Southern Pacific Railroad. Minneapolis: Green line data include adaptation of roadway bridge over Mississippi River.

It should also be recognized that the design requirements and installation costs of streetcar-type LRT projects average significantly lower than those of rapid or interurban-type LRT, particularly because of several factors. For example, streetcar alignments predominantly share street/arterial lanes with existing motor vehicle traffic. Stations often consist of simple “bulge-outs” from adjacent sidewalks, and are typically designed for single-car trains (i.e., single vehicles) rather than multi-car LRT trains. Also, the lighter static and dynamic loading requirements of some streetcar configurations facilitate the use of lower-cost “shallow slab” construction rather than the deeper excavation more typical of “heavier” LRT designs.

Capital costs and line lengths were aggregated for all eight LRT cases studied. Results are presented in the table below:


Data and calculation of average LRT project cost in street/arterial alignments.

Data and calculation of average LRT project cost in street/arterial alignments.


Hopefully, the information from this study will be helpful in developing realistic cost estimates for new LRT projects in these types of alignments. ■

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How Portland’s light rail trains and buses share a transit mall

LRT train on Portland's 5th Ave. transit mall swings to the curbside station to pick up waiting passengers. Photo: L. Henry.

LRT train on Portland’s 5th Ave. transit mall swings to the curbside station to pick up waiting passengers. Photo: L. Henry.

How can both buses and light rail transit (LRT) trains share the same transit-priority paveway or street? There are numerous examples that answer this, but certainly one of the best is in Portland, Oregon — the 5th and 6th Avenue transit malls.
Recently, the Austin Rail Now (ARN) blog posted an article focusing on Portland’s transit malls, and because of the more general usefulness of this information for many more communities, we’re re-posting it here with the kind permission of ARN.
The opening context for the article is the urban rail planning project currently under way by the City of Austin, Capital Metro (the transit authority), and a transit planning consortium called Project Connect. Transit priority lanes are now being installed on two major downtown north-south streets, and it’s been expected that urban rail trains would share these with buses, including the MetroRapid premium-bus services now being implemented in several major city corridors. However, some transit advocates are noting that these lanes may have insufficient capacity to handle all the bus routes plus MetroRapid, much less adding LRT into the mix.
Portland’s experience thus provides an illustration of how LRT trains and buses can share a priority alignment in a way that works well.

Capital Metro and the City of Austin have a project under way to designate “Transit Priority Lanes” on Guadalupe and Lavaca Streets downtown between Cesar Chavez St. and MLK Jr. Blvd. It’s mainly to expedite operation of the planned new MetroRapid bus services (Routes 801 and 803), but virtually all bus routes running through downtown will also be shifted to these lanes, located on the far-righthand side of traffic on each street (i.e., the righthand curbside lanes).

According to a 2011 study funded by the City of Austin, the Official (City + Project Connect) Urban Rail route is also envisioned to use these lanes downtown. Alternatives to the Official plan have also assumed that these routes would be available for alternative urban rail lines serving the Guadalupe-Lamar corridor.

However, there are legitimate questions as to whether these two lanes could simultaneously and effectively accommodate the two MetroRapid bus routes (10-minute headways each) plus all other Capital Metro routes (various headways) as well as urban rail (10-minute headway), all running in both directions.

Experience with both light rail transit (LRT) trains and buses sharing the same running way is rare in the USA, but one of the best examples can be seen in Portland, Oregon. For years, 5th and 6th Avenues through the downtown have been used by multiple bus routes as a transit mall, with a single lane provided for general motor vehicle access. In September 2009 LRT was added with the opening of the new Green Line; see: Portland: New Green Line Light Rail Extension Opens.

The integration of LRT with bus service in the 5th and 6th Avenue transit malls has worked well. Here’s a brief photo-summary illustrating some of the configurational and operational details.

• Buses and LRT trains share transitway

This illustrates how both bus services and LRT trains share the mall. Tracks, embedded in the pavement, weave from curbside to the second lane over. A third lane is kept open for mixed motor vehicle traffic.

Portland 5th Ave. transit mall. Photo: Dave Dobbs.

Portland 5th Ave. transit mall. Photo: Dave Dobbs.

• LRT routes cross

This photo shows how the Green and Yellow LRT lines on the 5th Ave. transit mall cross the Red and Blue LRT lines running on 5th St. You’re looking north on 5th Ave., and just across the tracks in the foreground, the LRT tracks on 5th Ave. weave from the middle of the street over to the curbside, where a station-stop is located. This allows LRT trains to access stations but otherwise pass buses stopped at bus stops on the same street.

Portland 5th Ave. transit mall. Photo: L. Henry.

Portland 5th Ave. transit mall. Photo: L. Henry.

• LRT train leaving station

Here an LRT train has just left the curbside station, following the tracks into the middle lane of the street. This track configuration allows the train to pass a bus boarding passengers at a stop.

Portland 5th Ave. transit mall. Photo: Dave Dobbs.

Portland 5th Ave. transit mall. Photo: Dave Dobbs.

• LRT train passing bus

Another train moves to the street center lane and passes the bus stop. Meanwhile, other buses queue up at the street behind.

Portland 5th Ave. transit mall. Photo: Dave Dobbs.

Portland 5th Ave. transit mall. Photo: Dave Dobbs.

• Bus bunching

Buses are prone to “bus bunching” (queuing) in high-volume situations because of their smaller capacity, slower operation, slower passenger boarding/deboarding, difficulty adhering to schedule, etc. However, notice how they’re channeled to queue up in a lane off the LRT track.

Portland 5th Ave. transit mall. Photo: L. Henry.

Portland 5th Ave. transit mall. Photo: L. Henry.

Can and will Austin and Project Connect planners learn anything about how to create workable Transit Priority Lanes from examples like this? Time will tell…