DENVER’S LIGHT RAIL

By Stephen Bulota

After a 44-year absence, public rail transit returned to Denver in the form of light rail on October 7, 1994. Denver once had an extensive network of streetcar lines operating on narrow 3’ 6" gauge track. Originally a cable operation overseen by the Denver Tramway Company, it was converted to electric and totaled 222 route miles at its peak. As in most other North American cities, streetcar lines in Denver were phased out after WWII in favor of buses, and service ended on June 3, 1950. In 1969, the Colorado General Assembly created RTD, or the Regional Transportation District, and service overseen by this agency began in 1974.

RTD had proposed a 77-mile light rail system in the late 1970s, calling for a 0.1% sales tax increase to help finance it. Voters rejected a proposal on the 1980 general election ballot. Most residents of metro Denver supported light rail, but didn’t like the idea of a sales tax increase. Luckily, the idea didn’t die. Ironically, most metro Denver residents today say they would support a tax increase if it would help build new lines faster.

The new line became popular right away, and ridership quickly exceeded expectations. Six additional vehicles were ordered to supplement the original 11-car fleet. This pattern repeated itself when the Southwest Corridor opened. The 14 cars ordered by RTD proved insufficient, and a dozen more were ordered to keep up with service demands. Ridership continues to exceed projections by as much as 56%. RTD proactively exercised the option to buy 34 additional cars on top of the 34 ordered for Southeast Corridor service.

Unlike the narrow-gauge Denver Tramway streetcars with trolley poles, today’s RTD light rail trains are equipped with pantographs and operate on standard gauge track. Track construction consists of welded rails secured with spring clips to concrete ties. Power is provided by overhead wire on street running portions and by Catenary along private ROW at a pressure of 825 volts DC. Most of the Catenary consists of center pole construction and counterweight tensioning.

The entire system is double-tracked with these exceptions: a five-block stretch of single track along Welton St. between 24^th and 29^th Streets; a third track at the Pepsi Center-Six Flags Elitch Gardens station and an added third track at the Broadway station. There is also a third track south of the Southmoor station that is used for short turns. Initial plans called for the original Central Corridor to continue along California and Stout Streets all the way to 30^th Ave. During public hearings, business owners in Five Points petitioned RTD to run the line along Welton St. instead. When RTD countered by saying it would be double-tracked all the way up Welton St., those same owners insisted on a single-track line for at least part of the way.

RTD has adopted the "It’s better to have it and not need it rather than needing it and not having it" philosophy of building connections even if they may not be used right away. Most major junctions permit any train to take one of two possible routes when approaching from any direction. While this may result in some normally-unused connectors, it does offer built-in flexibility and permits rerouting of trains when necessary. For example, the downtown loop connection at 14^th St. was used to turn back trains from 30^th Ave. via Stout, 14^th, and California when the line was closed between I-25/Broadway and 14^th Street due to construction on several occasions.

All train movements are governed by a combination of wayside block signals, traffic signals (on the street-running portion), radio communication, operations procedures, and train orders.