Green Line (MBTA)
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| MBTA Green Line | |
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|---|---|
| Green Line train at the Heath Street station | |
| Info | |
| Type | Light rail |
| Locale | Boston, Massachusetts |
| Terminals | East terminals: Lechmere (E) North Station (C) Government Center (B, D) West terminals: Boston College (B) Cleveland Circle (C) Riverside (D) Heath Street (E) |
| No. of stations | 66 (total) |
| Service routes |
|
| Daily ridership | 267,400[1] |
| Operation | |
| Opened | 1897 |
| Owner | MBTA |
| Operator(s) | MBTA |
| Character | Subway, grade-separated ROW, street-running |
| Rolling stock | Kinki Sharyo Type 7 Ansaldobreda Type 8 |
| Technical | |
| Gauge | 1,435 mm (4 ft 8½ in) (Standard gauge) |
The Green Line is a light rail/streetcar system run by the Massachusetts Bay Transportation Authority (MBTA) in the Boston, Massachusetts area of the United States. It is the oldest line of Boston's subway, which is known locally as the 'T'. The Green Line runs underground downtown and on the surface in outlying areas. With a daily weekday ridership of 267,400,[1] it is also the most heavily-used light rail line in the country. The line was given the green color because it goes primarily though the area of Boston called the Emerald Necklace of Boston.[citation needed] The four branches are the remnants of a once large system of streetcar lines, begun in 1856 with the Cambridge Horse Railroad. The Tremont Street Subway carries cars of all branches under downtown, and is the oldest subway tunnel in North America, opened in stages between September 1, 1897 and September 3, 1898 to take streetcars off surface streets.
Contents |
[edit] Description
The modern-day Green Line has its northern terminus at Lechmere station in eastern Cambridge. From there it runs south in the Tremont Street Subway under downtown Boston, and west in the Boylston Street Subway to Kenmore. Along the way, the "E" Branch splits to the southwest just west of Copley into the Huntington Avenue Subway, eventually running onto the surface and ending at Heath Street. The "B", "C", and "D" Branches all diverge west of Kenmore. From south to north, the "D" Branch surfaces onto the grade-separated Highland Branch, a branch of the Boston and Albany Railroad until 1958, running to Riverside. The "C" Branch surfaces onto Beacon Street, running to Cleveland Circle, and the "B" Branch runs along Commonwealth Avenue to Boston College.
The "A" Branch ran to Watertown until 1969. Although the route-letter scheme had been introduced two years prior to its closure, the "A" designation was never signed on streetcars operating to Watertown. It was, however, included in the destination signs on the Boeing-Vertol LRVs ordered in the mid-1970s, when reopening the Watertown service was still under consideration. The A line tracks remained in non-revenue service to access maintenance facilities at Watertown until 1994.
The elevated part north of downtown was closed from June, 2004 until November 12, 2005 for replacement of the Causeway Street Elevated with a tunnel under North Station.[2] The historic concrete Lechmere Viaduct across the Charles River remains.
The original Tremont Street Subway south of Boylston has been closed since 1962, as the lines feeding into it have been replaced by bus service. The Pleasant Street Portal at its south end has been covered over, but there are plans to build a new portal and reuse part of the tunnel for the Silver Line bus rapid transit line.
[edit] Rolling stock and accessibility
[edit] Active fleet
The Green Line's rolling stock as of the end 2007 includes:
| Year | Make | Model | Length (ft / mm) | Width (in / mm) | Gauge | Numbers |
|---|---|---|---|---|---|---|
| 1986-1988 | Kinki-Sharyo | Type 7 I | (36xx): 3600-3699, , 1986-88 (98 active) | |||
| 1997 | Kinki-Sharyo | Type 7 II | (37xx): 3700-3719 | |||
| 1999-2008 | Breda | Type 8 LRV | 74' | 11.8' | 4' 8-1/2" | (38xx): 3800-3894 |
[edit] Retired fleet
(Does not include even older cars from the Boston Elevated era)
| Year | Make | Model | Length (ft / mm) | Width (in / mm) | Gauge | Numbers |
|---|---|---|---|---|---|---|
| 1976-2007 | US Standard Light Rail Vehicle Boeing Vertol | LRV | 72' | 4' 8-1/2" | 150 | |
| 1937-1985 (still in use on Ashmont-Mattapan line) | Presidents' Conference Committee streetcar | PCC | 48' | 4' 8-1/2" | 10 |
Unlike the Red Line, Blue Line, and Orange Line, all of which run rapid transit cars and use stations with elevated platforms (so that the car floor is level with the platform and thus the cars are easily handicap-accessible), the Green Line is a trolley/streetcar line and has used a variety of trolley cars and light rail vehicles throughout its history. Like the other subway lines, it uses standard gauge tracks.
For many years, the line used the PCC streetcars developed during the Depression. These were finally phased out in favor of the US Standard Light Rail Vehicle supplied by Boeing-Vertol in the mid-1970s, but the chronic unreliability of the LRVs led to a PCC overhaul program and these cars were used into the 1980s in the subway. The introduction of these cars was heralded as part of an effort to rejuvenate mass transit in medium-sized metropolises.[3] Well into the 1980s this first series of LRVs were subject to chronic breakdowns.[4]
In 1987, 100 second generation LRVs were ordered from the Japanese firm Kinki Sharyo, with an additional set of 20 cars ordered and delivered in 1997. The last of the Boeing-Vertol cars were retired in March, 2007,[5] and the Kinki Sharyo cars now make up the bulk of the Green Line's rolling stock.
One of the earliest surviving pre-PCC cars, Type 5 5734, can still be seen parked on a sidetrack at the Boylston station, along with PCC 3295. These 2 cars used to be in working condition and were frequently used for fantrips.[citation needed][clarify] The most recent fantrip was in 1997, and now they sit at Boylston collecting dust. It is highly doubted that these cars are still in working condition, and Type 5 5734 reportedly has structural problems with the roof. Several of the surviving PCC cars are now run on the Ashmont-Mattapan portion of the Red Line. The San Francisco Muni F Market line historic street railway runs a PCC car in Boston colors, but that specific car never actually ran in Boston.
Originally, none of the Green Line stations included elevated platforms and the passengers had to step up into the vehicles, limiting accessibility for persons with disabilities. To address this, two changes have been made:[6]
- Elevated platforms and "wheelchair lifts" at some stops, and
- An attempt to phase-in low-floor streetcars and slightly raised platforms to allow direct boarding.
One hundred low-floor cars were purchased from the Italian vendor Ansaldobreda (Breda), with styling by Pininfarina. These have proven to be problematic and difficult to maintain. The first cars delivered failed every 400 miles (640 km), far less than the 9,000 miles (14,500 km) specified by the MBTA, and were prone to derailments. The MBTA has been forced to spend an additional US$9.5 million to modify tracks to prevent the derailment problems, echoing early problems with the Boeing stock. The MBTA has been criticized for their failure to assess Breda's reliability before entering into the deal and during the delivery of the vehicles.
In December 2004, the MBTA canceled orders for the remaining cars still to be delivered as part of the authority's 9-year, US$225 million-dollar deal with Breda.[7] One year later, in December 2005 the MBTA announced that it had entered into a restructuring of the deal with the Italian vendor, reducing the order to 85 cars (with spare parts to be provided in lieu of the 15 remaining cars), and providing for the remaining payment under the original 1995 deal only if the cars meet performance requirements.[8] Construction of the last car under the order was completed on December 14, 2006;[9] as of August 2007, 84 of the Type 8 cars were in service, and the scrapping of the Boeing-Vertol cars appears to indicate that the problems with the Breda cars' reliability have been overcome. In late 2007 the MBTA announced it had contracted with Breda to deliver another 10 cars, bringing the total order to 95 production cars and 5 car shells for parts.[10] Two of the additional cars are in service as of the end of 2007.
The Breda cars service the "B" line, the "C", the "E" line. The cars are scheduled to enter service on the "D" after several months of extensive track work.[11] The "D" line is still serviced by the aging Kinki Sharyo cars, many of which have become mechanically unreliable in their years of service, often resulting in long delays in service during cold weather. This has become particularly problematic on the D line, which extends through open, lightly wooded terrain outside the city for several miles.
The T runs 1, 2, and, rarely, 3-car trains on the Green Line, depending on travel demand and vehicle availability. As of April 2, 2007, 2-car trains now run from the start to end of service Monday through Friday; the MBTA has promised that each of these trains on the B, C, and E lines will contain at least one Type 8 car to facilitate access for disabled persons.
[edit] History
Today's Green Line was created by the Massachusetts legislature, but under private ownership, as the West End Street Railway in 1887. This system of horse-drawn streetcars was the merger of numerous independently operated railways built from the 1850s onward. At the time of the merger, West End operated 1,480 cars with a team of 7,816 horses.[12] The Allston - Park Square line (which served the general area of the "A" Branch, and is covered in that article) was the first section to be converted to electric traction in 1889, using modified existing horsecars outfitted with Frank J. Sprague's equipment first demonstrated in Richmond, Virginia. This initial line used overhead trolley wires for most of its length, but also third rail equipment supplied by the Bentley-Knight Electric Railway Company in sections where residents initially objected to overhead lines. The Bentley-Knight approach was abandoned soon after several horses were electrocuted due to inadequate insulation.[13] By 1889, the Sprague equipment was dropped in favor of Thomson-Houston (now General Electric) motors and generators, to which the rest of the system was converted.
In 1897, the West End Street Railway property was handed over to the Boston Elevated Railway (BERy) in the form of a 24 year lease, and the companies were ultimately combined. BERy, now under state ownership, is today's MBTA, with the Metropolitan Transit Authority (MTA) in the interim from 1947 to 1964.
As a tunnel built to get streetcar lines off the streets, rather than a rapid transit line, the Green Line has had many branches, with many services operating in many patterns. Additionally, many services from other companies, notably the Eastern Massachusetts Street Railway and its predecessors, have run into the subway from outer suburban points via BERy trackage. A partial list of these services is in the green rows on Boston-area streetcar lines.
In the 1970s the Green Line along with all other MBTA lines was re-evaluated by the BTPR for region-wide efficacy and future modernization alternatives initiated as far as physical plant and operating measures.
On May 28, 2008, two 'D-line' trains collided in Newton. The operator of one of the trains was killed and numerous riders were taken to the hospital with injuries of varying degrees of seriousness. Investigations are currently underway to determine the cause of this crash.[1]
[edit] Portals
Cars entered the subway from the surface at a number of portals or inclines, listed here from north to south/east to west.
[edit] Lechmere
Lechmere is the north end of the Green Line. From the opening of the Lechmere Viaduct leading to it in 1912 until 1922, streetcar lines simply fed onto the viaduct from Cambridge Street and Bridge Street (now Monsignor O'Brien Highway). In 1922 a prepayment station was opened, with a new loop for subway trains to turn around and a separate loop for surface cars, and no intermingling between the two. The surface lines have since been replaced with buses, but the Green Line still turns around at Lechmere.
[edit] Canal Street
The Canal Street Portal (also Haymarket Portal, North Station Portal or Causeway Street Portal, often referred to in revenue service as the Canal Street Loop, was part of the transition between subway and elevated railway on the Green Line, as it transitioned from the Tremont Street Subway to the Causeway Street Elevated towards the Lechmere Viaduct until 2004, when the Green Line north of North Station was closed for building of a new tunnel and portal. Certain trains turned at Canal Street, while others emerged from the subway to a viaduct to Lechmere. It was, however, possible for a passenger to alight from a train at Canal Street and proceed up a series of stairways to the Lechmere Viaduct. However most passengers desiring to continue to Science Park or Lechmere would have changed to a Lechmere signed car from a North Station signed car prior to the emergence from the central subway.
The original four-track portal opened in 1898 at the north end of the first subway; cars could turn east or west on Causeway Street. In 1901 the Charlestown Elevated was connected to the outer tracks, and streetcars only operated via the inner tracks. The Washington Street Tunnel opened in 1908, connecting to the Elevated via a new portal just east of the streetcar one, and all four tracks were once again open for streetcar use until 1975. In 1912 the Lechmere Viaduct opened, again using the two outer tracks for an elevated line. The inner tracks continued to serve the surface, including a surface station at North Station, until 1997, when they were closed for construction of the new tunnel and the Green Line was shifted to the old Orange Line (Charlestown Elevated) portal along the way. The 93 was the last service to continue onto surface streets from the portal, last running in 1949.
[edit] Pleasant Street
The Pleasant Street Portal was the south end of the Tremont Street Subway, opened one month after the original subway in 1897. It split from the Boylston Street Subway at a flying junction at Boylston, and another flying junction split the tunnel into two side-by-side tunnels to the four-track portal. The two west tracks rose onto Tremont Street and the two east ones onto Pleasant Street, later part of Broadway. From 1901 to 1908 the portal was only used by Washington Street Elevated trains, after which streetcar service was restored—though much of it had been cut back to Dudley for transfer to the Elevated. The last cars ran through the portal in 1961 as part of the 43, and in 1962 a shuttle service from Boylston to the portal was ended. The portal has since been covered.
[edit] Boylston Street
The first portal to open, on September 1, 1897, was the Boylston Street Portal or Public Garden Portal, providing an outlet for the subway on the north side of Boylston Street in the Public Garden. When the Boylston Street Subway opened in 1914, extending the subway west, the incline and portal were relocated to the center of Boylston Street. The last cars to use the portal ran in 1941 from Huntington Avenue, when the Huntington Avenue Subway opened as a branch off the main subway and the portal was closed.
[edit] Northeastern
The Northeastern Portal lies in the median of Huntington Avenue at the end of the Huntington Avenue Subway, just east of Northeastern University. It opened in 1941 and carries "E" Branch trains.
The incline was built as a wooden trestle to the street atop a level grade, as the original plans called for eventual extension of the subway; in the mid 1980s the trestle was replaced with fill (which greatly quieted the sound).
[edit] Kenmore
The Kenmore Portal or Kenmore Square Portal opened in 1914 with the building of the Boylston Street Subway west to the east side of Kenmore Square, in the median of Commonwealth Avenue. It closed in 1932 when the subway station at Kenmore was built and two new portals opened to the west.
[edit] Blandford Street, St. Marys Street, and Fenway
The Blandford Street Portal and St. Marys Street Portal, in the medians of Commonwealth Avenue and Beacon Street respectively, opened in 1932 as part of the extension of the Boylston Street Subway under Kenmore Square and the opening of the new Kenmore station. They are currently used by the "B" and "C" Branches respectively. The Fenway Portal opened in 1959 along with the opening of the Highland Branch, and provides a third exit from Kenmore, south of the St. Marys Street Portal. It carries trains of the "D" Branch.
[edit] Branches
The branches were given letters in 1967, two years after the green color was assigned to the line on August 26, 1965. The letters were assigned increasing from north to south, to the five remaining branches. No branches had used the Canal Street Portal except as a terminal since 1949 with the 93 or the Pleasant Street Portal since 1961 with the 43, and a shuttle until 1962.
The "B", "Boston College" or "Commonwealth Avenue" Branch is the northernmost of the three lines that split west of Kenmore. It travels west down the middle of Commonwealth Avenue, ending at Boston College. As of May 2005, regular B service turns around at Government Center.[update needed]
The "C", "Cleveland Circle" or "Beacon Street" Branch is the middle one of the three branches heading west from Kenmore, and the straightest, running down the middle of Beacon Street through Brookline to Cleveland Circle. As of May 2005, regular "C" service turns around at North Station.[update needed]
The "D" or "Highland" Branch is the southernmost of the three lines that separate west of Kenmore. It is the most recent branch, opening in 1959 along the former right-of-way of the Highland Branch of the Boston and Albany Railroad, and has full grade separation, entering the subway at the Fenway Portal. As of May 2005, regular "D" service turns around at Government Center.[update needed]
The "E" or "Arborway" Branch diverges from the other three lines just west of Copley. It travels mainly on the surface of Huntington Avenue, emerging from the Huntington Avenue Subway at the Northeastern Portal. Since 1985, service has been truncated to Heath Street, with continuing service to Arborway provided by the 39 bus. The "E" is the only branch to have a regularly used street-running section. As of November 2005, regular "E" service turns around at Lechmere.[update needed]
[edit] Former branches
- For a more comprehensive list, see Boston-area streetcar lines
The Green Line "A" Branch was the northernmost of the branches, running from the Blandford Street Portal, which is still used by the "B" Branch, west to Watertown, mostly street-running. The 57 bus replaced the streetcar line in 1969.
The Pleasant Street Portal hosted two services in its final days. The 9 to City Point ended in 1953, and the 43 to Egleston was cut back to Lenox Street in 1956, cut back to the portal in 1961, and ended operation in 1962. Prior to that, the 48 ran out Tremont Street to Dover Street and Washington Street, ending at Dudley, and last running in 1938.
The last two routes to continue beyond the Canal Street Portal both ran to Sullivan. The 92 ran via Main Street, last running in 1948, and the 93 via Bunker Hill Street last ran in 1949. Until 1997 trains continued to use the portal and its North Station surface station as a terminal.
In addition to the lines that later became the "E" Branch, the predecessors to the 58 and 60 split in Brookline, one branch running into the current "E" tracks and into the Boylston Street Portal, and the other running up Brookline Street to end at Massachusetts Avenue station. These were truncated in 1932 into a shorter route from Brookline Village to the subway via the Boylston Street Portal, which itself stopped running in 1938 (being cut back to Brigham Circle short-turn trips), three years before the closure of that portal.
The last "foreign" cars to operate in the subway were those of the Eastern Massachusetts Street Railway, running from the Canal Street Portal to the Brattle Loop at Scollay Square until 1935. It was then that the old Mystic River Bridge to Chelsea was closed to streetcars and the lines were replaced by bus service; the next year the BERy bought the Eastern Mass Chelsea Division and through-routed it with its lines connecting to the East Boston Tunnel at Maverick.
From the Lechmere terminal opening on July 10, 1922 to February 6, 1931, special service ran from Lechmere to various points on the subway. These trips were replaced on February 7, 1931 by extensions of the various branches from the west, which had terminated at Park Street, through to Lechmere.
[edit] Operations and signalling
The Green Line is signalled with advisory wayside signals except on surface portions in street medians or in-street running. Wayside signal territory stretches from Lechmere to the surface portals at Kenmore, and along the D-Riverside branch. There are no automatic protection devices, as the vehicles are equipped with track brakes--giving the operator the ability to stop quickly. Interlockings are controlled through a wayside Automatic Vehicle Identification (AVI) system that relies on the operator properly entering their destination manually on a roto-wheel in the train cab.
The Green Line is monitored from the 45 High Street rapid transit control room. Responsibility for controlling service is shared by the control room and field personnel located along the right of way. Track circuit and signal indications are not transmitted to the operational personnel sites. In lieu of track circuit indications, the AVI system is displayed in the control room to provide a periodic update to train position wherever AVI detectors exist. The AVI system user interface was solely text based until the current control room was opened, in which a new schematic display based on AVI data was instituted. Track circuit indications are available digitally in three signal houses but not transmitted to central control -- at Park Street interlocking, at the new North Station interlocking, and at the new Kenmore interlocking.
Plans to reinstitute a crossover for through movements from the terminating (inner) northbound platform at Park Street towards Government Center are expected to increase capacity on the Green Line.
[edit] Future plans
To settle a lawsuit with the Conservation Law Foundation to mitigate increased automobile emissions from the Big Dig, the Commonwealth of Massachusetts agreed to extend the Green Line north to Somerville and Medford, two suburbs currently underserved by the MBTA relative to their population densities, commercial importance, and proximity to Boston.
The initial recommended stops for the Green Line extension would be (starting in Somerville) Brickbottom at Washington Street, Gilman Square at Medford Street, Lowell Street, Ball Square, Hillside (between College Ave. and Winthrop St. in Medford, on the edge of Tufts University campus) and a terminus at Route 16 and Mystic Valley Parkway in Somerville (on the Mystic River. There is also an option for a branch splitting off after Lechmere stopping at Union Square in Somerville (or slightly south thereof, on the Fitchburg Line). This plan would extend the Green Line to Mystic Valley Parkway by the settlement-imposed deadline of December 31, 2014.[14]
Another mitigation project in the initial settlement was restoration of service on the "E" Branch between Heath Street and Arborway/Forest Hills. After some internal and community opposition, a revised settlement agreement resulted in the substitution of other projects with similar air quality benefits. The state Executive Office of Transportation promised to consider other transit enhancements in the Arborway corridor.[15]
[edit] Elevated or subway station listing
| Station | Location | Time to Park Street[16] | Opened | Transfers and notes |
|---|---|---|---|---|
 Lechmere |
Cambridge Street, Cambridge | 13 minutes (sign said 12) |
July 10, 1922 | "E" terminates here Viaduct to Lechmere opened June 1, 1912, with tracks running directly onto streets through July 9, 1922 |
| Science Park | Charles River Dam Bridge, Boston, serving the Museum of Science | 8 minutes | August 20, 1955 | |
| North Station |
Canal Street, Boston | June 28, 2004 | "C" terminates here Orange Line and Commuter Rail north side lines Surface station opened September 3, 1898 and closed March 27, 1997 Elevated station opened June 1, 1912 and closed June 24, 2004 |
|
| Haymarket |
Congress and New Sudbury Streets, Boston | May 10, 1971 | Orange Line Original station opened September 3, 1898 |
|
| Government Center | Tremont, Court, and Cambridge Streets, Boston, serving Boston City Hall and the Faneuil Hall/Quincy Market area | 2 minutes | September 3, 1898 | "B" and "D" Branches terminate here Blue Line Formerly Scollay Square until October 27, 1963 |
| Park Street |
Tremont, Park, and Winter Streets, Boston, serving the Boston Common | 0 minutes | September 1, 1897 | Red Line, Orange Line, and Silver Line |
| Boylston | Tremont and Boylston Streets, Boston, serving the Boston Common | 1 minute | September 1, 1897 | Silver Line Tracks used to split at Boylston to the Pleasant Street Incline |
| Arlington | Boylston and Arlington Streets, Boston, serving The Public Garden | 3 minutes | November 13, 1921 | |
| Copley | Copley Square, Boston | 4 minutes | October 3, 1914 | "E" Branch splits after Copley no crossover between directions at Copley; use Arlington to reverse direction |
| Hynes Convention Center | Massachusetts Avenue and Newbury Street (Boston), Boston | October 3, 1914 | Formerly Massachusetts until February 17, 1965, then Auditorium until March 27, 1990, then Hynes Convention Center/ICA until November 2006. | |
| Kenmore | Kenmore Square, Boston, serving Fenway Park | 12 minutes | October 23, 1932 | "B", "C", and "D" Branches split here |
[edit] See also
[edit] Notes
- ^ a b American Public Transportation Association, Light Rail Transit Ridership Report, First Quarter 2008.
- ^ Lechmere, Science Park stations reopen - The Boston Globe
- ^ U.S. DOT / Boeing brochure
- ^ Boston's Green Line Crisis
- ^ End of the line for T pioneers - The Boston Globe
- ^ MBTA > About the MBTA > Transit Projects > Transit Projects and Accessibility
- ^ Flint, Anthony. "MBTA Halts Purchase of Green Line 'Lemons'" (mirrored copy). The Boston Globe. December 12, 2004.
- ^ Green Line seeks zippier service with upgrade plan - The Boston Globe
- ^ Bredas - Starts & Stops - Boston.com
- ^ MBTA will take 10 new cars from company, saying past problems solved - The Boston Globe
- ^ Track work to close portions of the MBTA’s Green Line this summer - Local News Updates - The Boston Globe
- ^ Boston IEEE Section Techsite-MBTA Milestone
- ^ IEEE - IEEE History Center
- ^ Boston Globe article - Potential Green Line stops announced. May 7, 2008
- ^ Arborway public transit meetings to begin | Jamaica Plain Gazette
- ^ Association for Public Transportation, Car-Free in Boston, A Guide for Locals and Visitors, 10th ed. (2003), p. 117.
[edit] References
- Jonathan Belcher, "Changes to Transit Service in the MBTA District, 1964-2003" (PDF), Rollsign, November 28, 2003
- http://members.aol.com/rtspcc/roster/MBTAroster.html
[edit] External links
- MBTA - Green Line
- 100 Years of the Tremont Street Subway (a detailed history)
- Interactive Map (Unofficial)
- Green Line Extension Project Website
- STEP (Somerville Transportation Equity Partnership)
- Medford Green Line Neighborhood Alliance (MGNA)
- Mass.gov Executive Office of Transportation Plans for Green Line Extension
- Jamaica Plain Historical Society - Streetcars in Jamaica Plain: A History
- The Bentley-Knight Electric Railway System from The Manufacturer and Builder, January, 1889
- Operation manual for SLRV (Boeing) cars
- Video of LRV Boeing 3461 being scrapped at Riverside yard
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