Light rail systems are similar to streetcars in that they can coexist with automotive traffic to some extent. The greater the integration of automotive traffic into the right-of-way, the lower the average speed and reliability of the system. Rapid transit systems, on the other hand, have reserved right of way, and use heavier, larger vehicles (hence the alternate name "heavy rail").
Buffalo's Metro Rail is a hybrid system that blends features of light rail and heavy rail. Metro Rail is designed for convenient service on the Buffalo Place transit mall, which occupies the southern 1/6th of the route. Convenience is offered by closely-spaced stations.
The balance of the rail system is presently the tunnel that forms the rapid transit portion of Metro Rail. Here, the system is designed for rapid travel, with long distances between stations.
This system design largely represents the state of the art of light rail rapid transit construction from the 1970s, when Metro Rail was first envisioned. Metro Rail was originally envisioned as a heavy rail system but was changed to a hybrid system. This allows Metro Rail greater flexibility in expansion than a conventional rapid transit system would, especially since Metro Rail vehicles use an overhead catenary  for power as opposed to third rail .
Because any expansion of a high quality transit system requires significant financial and political capital and will, on its face expansion is a difficult prospect. However, further examination shows that expansion has been accomplished with every non-new build light rail system in North America except Buffalo's. Newly built systems have not generally had enough time to secure a ridership base and therefore do not always expand; however one has commenced construction already (Seattle's Link Light Rail). The expansions have occurred in cities of varying populations, some of the same populations as Buffalo, and even smaller. The cities represent a vast spectrum of economic conditions; some cities have had consistent recessions while others possess stable or expanding economies.
This report will expose the reader to several recent expansions of transit systems in the United States. All extant light rail systems in Canada have expanded, some with aggressive expansion programs. However, the regulatory environment, public planning and transit utilization are largely different in Canada; thus Canadian expansion will be referred to only in passing. As examples, Vancouver is undergoing an extensive light rail expansion to its airport, as well as extensions to eastern portions of its urban area. Toronto's "Transit City" expansion program is even more aggressive, adding new, longer streetcar lines and some expansion of heavy rail transit service.
There is a common thread between many of the expansions that have occurred—whether they are in the United States or Canada. The expansions represent long commitments to public transportation in many of the cities. The projects were often funded or supported by changes in sales tax allocation (not tax raises) or have been supported by propositions voted on by constituents. Some systems have realized expansion opportunities due to the American Recovery and Reinvestment Act of 2009 (colloquially, the "stimulus").
As stated before, due to the infrastructure investment, it is necessary to have public and political support. This section covers the experiences of many cities in the United States, of varying political and economic climates. There are other cities covered that have had expansions in previous years but have focused on maintaining their current network with available funds.
In Charlotte, North Carolina, the LYNX Rapid Transit began operation in 2007 with a 9.6 mile new build. Interestingly, the system was in danger of losing its supporting tax, but voters rejected repeal 70 to 30 percent in 2007. By March 2008 LYNX ridership has doubled its opening year projections. Currently, an 11-mile extension (Blue Line) is in planning to go to UNC Charlotte by 2015.
Dallas, Texas has two new lines (Green and Orange) under construction; Orange is to serve Love Field and eventually Dallas-Fort Worth International Airport by 2013. The Green Line stretches from northwest to southeast Dallas. Service to the State Fair of Texas slated to open Fall 2009. In related news, the Trinity Rail Express, the commuter rail service for the Metroplex, is being double-tracked for extra capacity.
Denver, Colorado has seen the debut of new, expanded suburban service. The T-REX (southeast corridor) was shown to be popular since its completion in 2006. The T-REX project is unusual for transit projects in the United States, where an Interstate highway (I-25) is reconstructed with rail placed alongside it. The West Corridor Light Rail is currently under construction.
Los Angeles is a city not popularly associated with transit, but it has been pursuing aggressive rail expansion. The Expo Line is currently under construction westbound past the University of Southern California, to Culver City. Completion of this segment of the line is slated for 2010, and it is eventually planned to reach Santa Monica. Meanwhile, a Gold Line expansion is under construction to East Los Angeles. A Gold Line eastward expansion (Foothills) to Azusa is in its final design stage, with Federal Transit Administration (FTA) approval pending.
In Minneapolis and Bloomington, Minnesota, the Hiawatha line expanding to the new Twins baseball stadium in a multi-modal  terminal. The station will also be terminal for the Northstar Line commuter rail, also opening this year between Minneapolis and St. Cloud. The Minnesota Twins actually pledged 2.6 million for the station, which represents an option of a public-private partnership. A new station is also projected for Bloomington, the suburb to the south.
New Jersey Transit has long been an aggressive entity in expanding its high quality transit; it has three separate light rail systems. The second newest of the three, the Hudson-Bergen Light Rail, is adding a station in Hoboken. The Newark City Subway joined with a new Network Light Rail in downtown Newark, serving Riverfront Stadium.
In Pittsburgh, a city of nearly the same population as Buffalo , and having had tough times economically, the North Shore Connector is now under construction with a scheduled completion in 2011. Twin bored tunnels below the Allegheny River depart from Gateway Station to the North Side station near PNC Park, with another station serving Heinz Field. Eighty percent of the funding is federally provided for this project. The Port Authority of Allegheny County may also be considering expansion to Pittsburgh International Airport.
Phoenix, Arizona is another city that is not popularly associated with public transit, due to its postindustrial development. Its region now possesses the new METRO Light Rail. The system debuted at 20 miles through Phoenix, Tempe and Mesa. There is a Northwest extension of this new build in the engineering stage, for a four-mile route to Metrocenter Mall. It is important to have major destinations on light rail expansions; this new build and extension is a good example of that with service to Arizona State University, downtown Phoenix, and malls.
In the Pacific Northwest, Portland, Oregon has been recognized as a leader of public transit expansion and planning, despite the soft economy. Portland's MAX Green Line (14 miles) is currently under construction between Clackamas Town Center and Portland State University, scheduled to open this year. Also slated to open this year will be the Loop Shuttle between Portland State University and Union Station. These expansions follow 2004’s Yellow (2004) and Red Lines (2001). Portland has more than doubled its trackage since the system was first opened in 1987.
Sacramento, California is accomplishing some rail expansions as well, to make an intermodal connection with Amtrak. A South Line extension slated for completion this year, to Cosumnes River College.
St. Louis, Missouri is an important example to consider, due to the fate of its central city—the city, like most large cities in the United States, has seen heavy suburbanization and population loss. Despite this, major expansions of St. Louis's Metrolink brought light rail to near Scott Air Force Base/Mid America Airport (2003) and—more recently—Shrewsbury in the western suburbs (2006).
Aggressive rail expansion has occurred in Salt Lake City, a city far smaller than Buffalo. Utah Transportation Authority (UTA) TRAX expanded to the Salt Lake City Intermodal Hub in April 2008, following expansions in 2003 and 2001. Three new lines are currently under construction–the Mid-Jordan, West Valley City, and Airport Lines. Completion is expected between 2011 and 2012. The lines are funded by sales tax and federal funding.
In San Francisco, California, the Third Street Light Rail project expanded the Municipal Railway (MUNI) light rail to Visitacion Valley along the east side of the city, opening in 2007. As another example of service to major destinations, one station partially serves 3Com Park and has an interchange with CalTrain at two locations. The Central Subway is in its planning stages and would extend this line to cross the Muni Metro and Bay Area Rapid Transit (BART) subway under Market Street.
Seattle's Central Link light rail between Seattle and Sea-Tac Airport opened July 2009, with the South Lake Union Streetcar already open (1.3 miles) in downtown Seattle. Expansion of Link Light Rail was already approved in Sound Transit’s Proposition 1, November 2008. Accordingly, the University Link extension is already under construction to the University of Washington campus. This facilitates further northward expansions.
How does Buffalo fit in? As stated before, Buffalo's Metro Rail is the only non-new build system that has not expanded. Cities that have had declining populations have managed to have expansion (Pittsburgh, Newark). Cities that have had large-scale job losses and economic changes have also expanded systems (Pittsburgh, Cleveland, and Portland as examples). Even cities that have not been associated with public transit advocacy have built new systems (Houston, Los Angeles, Phoenix).
Aggressive, forward-thinking planning can help secure resources necessary for public transit expansion. It is commonly, though erroneously, believed that the only way to secure monies for public transit expansion/operation are through local tax increases and direct spending. However, there are numerous attractive options such as design/build or design/build/operate methods for construction, and public-private partnerships.
In order to secure public support, it is necessary also for transit agencies to be proactive and undergo planning to obtain credible cost figures to help politicians make the case. Proactive transit agencies and political leadership can achieve great things even in the most surprising places. And above all, the leadership must embrace the community and be sensitive to its transit needs.
High-quality public transit is an effective component of a city's planning toolbox, and can be a very important piece of the puzzle for kick-starting reinvestment and/or redevelopment in diminished neighborhoods. Unlike bus service, rail expansion represents an investment of some permanence in an area, signaling to developers that the area will be well-supported economically. This actually lowers the perceived risk for new development. High-quality rail transit can be an opportunity to reuse community assets (in the case of Buffalo, the Central Terminal) and connect more people to employment. Systems like Buffalo's Metro Rail are also a great benefit environmentally; Metro Rail itself is powered by clean hydroelectric power from Niagara Falls. As is commonly experienced, care for the environment brings forth greater quality of life in a community.
Buffalo has an asset and opportunity that relatively few cities possess in North America. The city and region will benefit greatly from tapping into the full potential of that very asset.
Sources: Transit agency sites of the above cities