Light-Rail Transit (LRT)

Introduction

Light-rail transit (LRT) is rapid transit that operates electric-powered single cars or short trains on fixed rails. Light refers to lighter passenger capacity, not the physical weight of the vehicles. Today’s LRT originates from traditional streetcar systems but is redesigned to run faster and carry more passengers over greater distances in a metropolitan area.

LRT vehicles can run in highway medians or on streets with at-grade intersections like streetcars. Generally, LRT runs along fully dedicated rights-of-way to reduce the impact from and to adjacent traffic. Sometimes, LRT systems use abandoned railroad rights-of-way, underground tunnels, or even drainage canals to avoid roadway traffic and adjust to the physical environment. If separated crossings are not provided, transit signal priority is given to LRT to minimize delay and waiting times at intersections.

Like heavy rail, LRT serves widely spaced stops to cover long distances and ensure higher speeds. However, LRT may make more frequent stops similar to streetcars in downtown areas to provide more access to passengers.

Executive Summary

Interurban Commute
LRT best provides quick and cost-effective service for interurban transportation in a metropolitan area. It is designed to address a large gap between local buses and heavy rail. LRT flexibly carries large volumes of commuters to and from the city center with relatively higher speeds than local buses and at a lower cost than heavy rail.

Medium-Size Cities Willing to Invest in Mass Transit
In recent years, LRT systems have also become increasingly popular in some medium-size cities. These cities seek the benefits of rail-based mass transit but lack ample demand to support fully grade-separated systems.

• Operates at faster speeds and accommodates greater capacity than other transit modes, including light rail and bus rapid transit. Top speeds between stations can reach up to 75 mph, and heavy rail handles a rush-hour capacity of between 600 and 2,400 people per train.²
• Promotes economic and land development along corridors and stations through improved access and mobility.
• Offers more flexibility in station locations and routes than other rail systems. Although it often runs on the street with auto traffic, light rail can operate underground, on elevated platforms, on other railroad rights-of-way, or even in canal beds when necessary.

• Offers a cost-effective solution on high-volume corridors with a higher capacity than buses (including bus rapid transit). LRT requires a significantly smaller investment than highways, heavy rail, and commuter rail. LRT can also minimize expenses by integrating with existing transit infrastructure.
• Attracts more riders from other modes by providing passengers a better riding experience. LRT is comfortable, fast, quiet, and safe. Riders may choose to be productive or relax, making up for lost time in a car.
• Is environmentally friendly. Electric-powered light rail reduces emissions and produces less noise than other transit modes, especially for an equivalent volume of automobile traffic.

LRT is successful in interurban corridors with high transit demand. Job and population density is an important consideration to offset LRT’s initial investment and continuous operating costs.

Research conducted by the University of California, Berkeley Institute of Transportation Studies suggests that light-rail systems require around 30 people per gross acre around stations.¹ The following table presents the minimum population density to support a light-rail system for an average city. The different costs per mile are based on an analysis of rail systems in the United States.

Because LRT often operates in urban settings, it is limited by the existing environment, such as adjacent buildings or street network. The urban setting may restrain track construction or require sharp turns and steep grades—all dramatically increasing initial cost. When designing new LRT lines, a minimum curve radius of 82 feet and a maximum gradient of 10 percent are the standard limits for passenger comfort.²

Most North American LRT systems use articulated cars, which can operate individually or assembled into short trains to accommodate more passengers. A two-car Siemens S70 rolling stock can carry 456 passengers with up to 144 seats.³

LRT cars draw power from an overhead line. Modern electronic propulsion and braking control let them move rapidly and stop quickly. Most LRT systems average speeds of 10 to 30 mph, though they may reach speeds of 66 mph using the latest technology.²

LRT uses widely spaced stops for rapid operation. Stops are about two to four blocks (0.5 miles) apart. This spacing is wider than for bus rapid transit but closer than for heavy rail or subway stops.⁴ A light-rail stop can be as simple as a bus stop or as integrated as a multi-use transit center.

LRT requires large initial infrastructure investments and cannot operate without the assistance of government funding. For LRT operating on existing local streets, transit agencies often provide extensive street and aesthetic upgrades like shade, street benches, and amenities to attract bicycle and pedestrian users to boost ridership. These upgrades may require significant additional investment. For LRT on rights-of-way separated from auto traffic, additional costs include stout bridges, elevated structures, or tunnels, which significantly increase capital costs.

Before these systems can be self-sufficient, they need initial subsidies from local sales taxes and/or state and federal grants for a period of time. During system construction, traffic and adjacent business may be seriously disrupted, temporarily impacting the area’s profitability.

Arguments exist about light rail’s traffic congestion benefits. Critics claim that LRT cannot move as many people as one freeway lane (some systems take up the same amount of space in order to operate at top speeds). Therefore, opponents say LRT does not provide a significant net improvement to traffic. Proponents argue that LRT attracts ridership from auto commuters, reducing the demand for new roadway space and improving congestion.

Other concerns about LRT include:

• At on-street LRT stations, pedestrians have little to no protection on the tracks or from the train.
• Local business owners may be concerned about losing store-front parking in order to build an LRT system. While this may be a concern for some, LRT may actually increase customers.
• Light rail may divide communities based on how tracks are laid and fenced through neighborhood districts.

Who Is Responsible?

Local transit authorities, metropolitan planning organizations, and city planners are responsible for planning, designing, and implementing light-rail systems. Other local and regional groups or stakeholders in the light-rail planning process include neighbors, business owners, and public interest groups.

Cost

Cities with LRT range in population from 1 to 3 million people. On a per-mile basis, LRT costs between $20 million and $80 million per mile. The cost of LRT depends on station properties, whether existing right-of-way is already owned by the constructing agency, and how much of the rail line is elevated, at ground level, or underground.⁵

A comprehensive planning process guides the design, implementation, and operation of all LRT services. Prior to implementation, an initial planning study should review all potential new lines or service changes to:

• Determine the feasibility and structure.
• Identify necessary local commitments and funding availability.

Santa Clara Valley Transportation Authority provides the following guidelines to evaluate existing and proposed service:

Existing Service Evaluation

• Step 1: Assess existing service versus established service standards.
• Step 2: Devise and implement an improvement plan, if necessary.

Implementation of New Service

• Step 1: Conduct market research and estimate ridership and revenue potential.
• Step 2: Evaluate the new service with the Transit Sustainability Policy methodology.
• Step 3: Identify and design route alignments.
• Step 4: Establish the LRT station locations.
• Step 5: Design stations, facilities, and street improvements.
• Step 6: Develop an operating plan and implementation schedule.
• Step 7: Develop a marketing plan and brand management strategy.