Nearly 50 years after the city’s last streetcars were retired, Minneapolis’ rail rebirth began in June 2004 with the opening of the first phase of the Hiawatha Light Rail Line. Operations began in earnest, with a huge opening weekend crowd of 87,000 riders, and ridership exploded from there, surpassing expectations during its first phase by more than 100%. After the remainder of the line opened in December of that year, the 11.6-mile Hiawatha line proceeded to show steady growth, breaking ridership records consistently over the course of 2005 and creating a success model for urban rapid transit. Hiawatha’s success has been so profound, in fact, that it has led the city to consider implementing rail projects in several other heavily traveled corridors. Specifically, Minneapolis officials continue to discuss options for a light rail line downtown and a commuter rail line on the north of the city. The transit picture in the Twin Cities owes much of its promise to smart planning and construction, investment in technology and cooperation among a forward-thinking consortium of stakeholders. Hiawatha’s story
The Hiawatha line — a $715.3 million project — is owned by the Metropolitan Council and operated by Metro Transit. Construction was managed by the Minnesota Department of Transportation using a design/build procurement method for approximately $320 million worth of civil and systems construction. The consortium that designed and built the Hiawatha Line was a joint venture known as Minnesota Transit Constructors, consisting of Granite Construction Co., C.S. McCrossan Inc., Parsons and Edwards and Kelcey Inc. In addition, the firm TKDA was a major subconsultant and performed architectural design for the stations and the operations and maintenance facility. As noted, acceptance and enthusiasm for the system within the community has been, from the start, outstanding. In September 2005, ridership was 81% above projections (770,000 actual vs. 425,000 projected). Growth for December 2005 was 22% above December of the previous year. Overall, 7.9 million riders used the system in 2005. Among factors most responsible for the inflated ridership (compared with expectations) is the fact that the average number of riders on weekends has been about four times the projection. Another unexpected bounce was that on weekdays, office workers in the downtown are taking the train to restaurants “down the line” for lunch. Events at the Metrodome — home of the Minnesota Vikings, Minnesota Twins and University of Minnesota Golden Gophers — are well served by the Hiawatha line. Ridership has been so strong that plans have been made to expand a 600-space parking facility at the 28th Avenue Station — one of two stations with park-and-ride facilities. Plans are also being made to construct an additional station in Bloomington, which was deferred in the initial construction plans. Transit-oriented development (TOD) has also been occurring along the corridor. A number of smaller projects and fill-in projects in Minneapolis have rounded out the Hiawatha line. For example, the city is pursuing residential development adjacent to four light rail stations. Construction of several condominiums within walking distance of train stations began while the line was still under construction. Also, a $700 million mixed-use development project is underway, centered on Bloomington Central Station. Phase I is currently under construction with two 16-story towers comprising 267 units. A railcar resurgence
Rolling stock for the line was manufactured by Bombardier Transportation, which supplied Metro Transit with “Flexity Swift” light rail vehicles (LRVs). The 94-foot vehicles are low-floor and articulated in three sections, with three trucks supporting them. The center section is just longer than the truck supporting it. Each end section is symmetrical with driver controls at each end of the LRV for bi-directional operation. The vehicles seat 66 passengers and can accommodate up to 180 passengers total. Each vehicle has accommodations for bicycles and luggage racks. The first vehicles delivered were manufactured in Mexico and delivered by truck. Vehicles delivered later had major structural sub-assemblies manufactured in Mexico, but were assembled in Plattsburgh, N.Y. Bombardier assembled a work force in Minneapolis during the commissioning and training phase prior to the start of revenue operations. As a result of high ridership, a total of 24 LRVs have been delivered, after an initial order of 18. The LRVs are generally operated in two-car trains. At off-peak times, single car trains were originally used, but high ridership during mid-day and weekends has also limited the use of single-car trains. The LRVs are stored and maintained in Metro Transit’s operations and maintenance facility. The shop contains state-of-the-art equipment, including a wash bay, body shop and eight maintenance bays. Each maintenance bay is equipped for specialized maintenance functions, and they include a variety of overhead bridge cranes and monorail hoists, vehicle lifts, maintenance pits, material hoists and other specialized equipment, including a wheel-truing machine and a turntable for trucks. The shop is laid out for access under, in, around and on top of the vehicles. It has equipment for rebuilding electrical parts as well as making mechanical repairs. The LRVs are powered by an overhead contact system (OCS) that supplies 750 volts DC. Power is supplied to the OCS from 14 1.5-megawatt substations located every three-quarters of a mile along the line. There is an additional rail yard substation that is rated at 2.5 megawatts. The traction power system is designed so that if any of the substations lose power, transfer trip switches will reroute power to the line segment served by the disabled substation from the adjacent substations. Communications and control
The administrative offices and rail control center (RCC) are located in the maintenance facility. A storage shed — completely enclosed and conditioned to protect the vehicles from temperatures that can reach -30 degrees Fahrenheit during the harsh Minnesota winter — is located on the opposite side of the administrative offices. The rail yard includes room for expansion of the storage shed in the event that additional LRT lines are added. Each of the line’s OCS substations was delivered to the site as a pre-packaged unit fabricated offsite and set on a foundation at each location. Substations and the grounding grids that are located in residential or commercial areas are enclosed in screen walls with differing architectural treatments to better blend with the surroundings. Substations that are on the airport property, or in the yard are protected by a chain link fence and do not have an architectural treatment. The train control signal system utilizes an automatic block signal (ABS) system to control headway requirements — train-to-wayside communications; update the computer system displays in the RCC for train locations, train numbers, car numbers and routes; call routes through interlockings; pre-empt highway traffic signals; and call switches in the yard. There are six interlocking locations and 18 grade crossing warning systems for highway and pedestrian grade crossing on the line. The train control signal system interfaces with three separate highway traffic signal systems. Downtown Minneapolis traffic signals are centrally controlled as a grid network of signals. The traffic signals along Hiawatha Avenue — the Hiawatha line parallels this street for 22 blocks — are interconnected arterial signals. Traffic signals in the City of Bloomington operate as a separate system. The communications system has a fiber optic backbone that carries data and video. Some of the communications subsystems include SCADA, train-to-wayside communications, fare collection system communications, telephones, public address systems, readerboards, closed-circuit televisions, tunnel radio systems, intrusion alarms and the tunnel emergency management panel. For safety and security, a minimum of four fixed cameras are mounted at each station with views of the platform edges, ticket vending machines and other strategic points. Park-and-ride lots are covered using pan, tilt and zoom cameras. Track, infrastructure issues
Hiawatha trains travel trough two tunnels between downtown Minneapolis and the Mall of America at the southern end of the line. The northerly tunnel is a cut-and-cover tunnel approximately 800 feet long, built as part of the reconstruction of Hiawatha Avenue. As part of the environmental review process for the highway, provisions for future transit were included in the highway plans, and a third barrel was included with the highway tunnel for transit. Access under the Minneapolis/St. Paul International Airport is provided by twin tunnels bored through sandstone using a tunnel-boring machine. These tunnels are approximately 8,000 feet long and lie as much as 70 feet below the ground surface. Near the mid-point of the tunnels, a cavern was mined out of the rock for a station serving one of the airport’s terminals. Two new post-tensioned concrete box girder viaducts carry the Hiawatha Line over highways. The viaducts total 4,000 feet in length, with the Crosstown Viaduct measuring about 1,500 feet long, and the Lake Street Viaduct approximately 2,500 feet. Four abandoned railroad bridges were rehabilitated to carry the light rail line and a parallel bike path. In an innovative display, the through girders and abutments from an existing single-track bridge were modified and reused for a two-track bridge near the Metrodome. The lower load of the LRVs and maintenance equipment, compared to the original load the girders were designed for, allowed the girders to support two tracks instead of one. Several different track types are used throughout the system to accommodate varied conditions. All rails for the mainline and yard are 115-pound rail. The rails were mechanically distressed to 95 degrees Fahrenheit to account for the wide seasonal temperature variations experienced in Minnesota. Embedded track was used in downtown Minneapolis, and adjacent to and in the Mall of America in Bloomington, where the tracks are located in, or adjacent to roadways. Embedded special trackwork is required at several locations to accommodate the crossovers necessary to change the direction of travel at each end of the line and for emergency crossovers. Through the Airport Tunnel and its approaches, a dual-block, low-vibration track system was used. Direct fixation track was utilized on the Crosstown Viaduct. The other bridges and the remainder of the mainline track is ballasted track. The transit horizon
Looking ahead, the Hiawatha line offers great prospects for becoming the start of an emerging multimodal regional transit system for the Twin Cities. Many cities with new light rail lines have quickly added more lines to meet the demand, and Minneapolis looks to be no exception to this rule. For example, the Northstar Commuter Rail is currently under design. This $289 million project extends 40 miles from Minneapolis, north to Big Lake, Minn. The Minneapolis terminus will be a multimodal facility to allow passengers to transfer to buses and the Hiawatha Line. To reach this multi-modal station, the Hiawatha Line must be extended approximately four blocks to the west from the current end of its line. Ridership projections for the Northstar line are 5,600 passengers each way by 2025. With the added passengers transferring from the Northstar line, and the continued growth in riders that Hiawatha is experiencing, this new service could be the catalyst that drives the need for the operation of three-car trains on the Hiawatha Line. The design of Hiawatha was set up to accommodate this configuration. For station platforms that were initially constructed at 200 feet in length, provisions were made to allow eventual expansion to 300 feet. The traction power system was sized to accommodate three-car trains at 7.5-minute headways. Furthermore, based on the success of the Hiawatha line, planning continues on the Central Corridor Light Rail Project, a proposed line that will connect downtown St. Paul to downtown Minneapolis. The latest estimates for construction costs are $840 million for the 11-mile line, which will join the Hiawatha line near the Metrodome on the east edge of downtown Minneapolis. At present, opening of this line is projected for 2012. Design work to gain FTA approval and allow preliminary engineering to start is ongoing.
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