Are trolley lines more than just a fashionable bit of nostalgia?

By Roger K. Lewis
Friday, October 8, 2010; 5:30 PM

Is an urban light-rail line, also known as a trolley car or tram line, a cost-effective, efficient mode of transportation for the increasing number of cities building them? Or are they just fashionable - a manifestation of nostalgia?

In recent years new light-rail lines have appeared in improbable places. The attractive trolley line built in Salt Lake City before the 2002 Winter Olympics seems primarily ornamental. A line was built a few years ago in sprawling, auto-dependent Houston, where public mass transit is essentially an oxymoron. But its purpose was not to solve Houston's mobility problems but to spur growth in a portion of the city.

Arlington County plans to construct a light-rail line along Columbia Pike, a busy commercial and residential corridor much in need of both functional and aesthetic enhancement. There, too, the rationale for the trolley line goes beyond meeting transportation needs.

By contrast, trolleys in Portland, Ore., are an essential component of the city's transportation system. Free for short, hop-on-and-off downtown trips, Portland's light-rail network also serves suburban commuters and keeps thousands of cars off city streets every day.

Closer to home, the Purple Line through Montgomery and Prince George's counties will be the first step in adding much-needed circumferential light-rail lines to augment the region's radial Metrorail network.

In fact, as transportation infrastructure, light rail is effective only when it is part of a diversified, integrated system. A single light-rail line by itself is rarely cost-effective if its only purpose is to move riders from origins to destinations along the line, an objective that usually can be achieved less expensively with buses.

Unlike a bus line, a trolley line is a relatively permanent infrastructure investment. Thus with fixed rails and stations, a trolley line can positively affect real estate values and greatly augment economic activity near the line. Property owners, developers and lenders are more willing to incur the risk of investing in projects near a trolley line than in projects near a bus stop.

Likewise, people who prefer living in cities are more strongly attracted to residential opportunities within walking distance of well-designed rail transit. Clearly, urban housing accessible to a trolley line is more marketable.

In the long run, investing in light rail can be economically beneficial for a city by increasing real estate values, business activity, jobs and tax revenues associated with the transit corridor. And increased tax revenues attributable to transit help cities finance and recover capital investments in transit.

Two trolley lines are now under construction in Washington. One runs along H Street and Benning Road NE. The other runs along Martin Luther King Jr. Avenue SE and will serve Anacostia. The District is building these lines to achieve two goals: promoting development and redevelopment, and improving transportation.

The District's long-range transportation goal is to create a light-rail network interconnecting several central city neighborhoods and complementing Metrorail and Metrobus networks.

Planners seek a multi-modal system made up of the three transit networks; an improved vehicular network of streets and avenues with sidewalks and bicycle lanes, plus state-of-the-art directional graphics and traffic control technology; and hiker-biker trails weaving around and through the city.

But a hitch can arise in achieving the city's economic goals. Zoning and historic land use patterns may constrain potential transit benefits, exemplified by the District's H Street line, where commercial zoning applies only to lots directly abutting H Street.

The area of economic impact ideally would encompass higher density and mixed residential and commercial uses that extend beyond the one-lot-deep strip of properties on each side of H street. If they had their way, urban designers would stretch and rezone the transit-affected real estate corridor, increasing its width by several blocks.

Will real estate within a few minutes' walk of H Street ever be rezoned? Probably not before the trolley line is up and running. But if the trolley operates effectively and provides the amenity and convenience hoped for, perhaps the urban design and rezoning aspirations of city planners will be realized.

And maybe the rest of the city's trolley lines will get built as well.

Roger K. Lewis is a practicing architect and a professor emeritus of architecture at the University of Maryland.

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