Fern Hollow Bridge Explained

Fern Hollow Bridge
Coordinates:40.4394°N -79.9003°W
Owner:PennDOT
Maint:City of Pittsburgh
Website:https://www.penndot.pa.gov/RegionalOffices/district-11/ConstructionsProjectsAndRoadwork/AlleghenyCountyConstruction/Pages/FernHollowBridgeProject.aspx
Design:three-span continuous composite pre-stressed concrete I-beam with integral abutments
Material:concrete
Width:64feet
Number Spans:3
Lanes:4
Contracted Designer:HDR, Inc.
Builder:Swank Construction
Begin:May 9, 2022
Complete:December 2022
Opening:-->
Inaugurated:December 20, 2022

The Fern Hollow Bridge is a series of three bridges in the East End of Pittsburgh, Pennsylvania, United States; each bridge carried Forbes Avenue over a large ravine in Frick Park. The first Fern Hollow Bridge opened in 1901 as a steel deck arch, and was demolished in 1972 while the second bridge was being built. The second bridge opened in 1973 and collapsed on January 28, 2022.[1] Construction of the third bridge began on May 9, 2022, and the third bridge was dedicated on December 20, 2022.

The bridge lies west of the intersection of Forbes Avenue and South Braddock Avenue, connecting the Squirrel Hill neighborhood with the neighborhoods of Point Breeze and Regent Square.

First bridge (1901–1972)

In February 1900, the "Councils of the city of Pittsburg" appropriated $100,000 for the construction of a street railway and highway bridge across Fern Hollow. A steel deck arch bridge was completed by Schultz Bridge & Iron Works (steelwork was subcontracted to American Bridge Company) and accepted on September 28, 1901.[2] [3] The central arch spanned with a rise of ;[2] [4] [5] overall, the 1901 bridge was long and the vertical clearance under the bridge was approximately above the valley floor,[2] although later press reports stated it varied between .[6] [7] The roadway was wide, flanked on both sides by concrete sidewalks each wide. Unusually, the 1901 bridge was not built level, with one end being higher than the other.[5] The four-lane bridge also carried double rail tracks for streetcar service.[8]

Second bridge (1973–2022)

Fetchwikidata:carries,crosses,locale,owner,maintained,upstream,downstream,iilength,width,height,mainspan,spans,below,designer,architect,builder,cost,inaugurated,replaces,replaced_by
Coordinates:40.4394°N -79.9003°W
Inaugurated:June 1, 1973
Collapsed:January 28, 2022
Opened:December 22, 2022

The 1901 bridge was replaced in 1973. The old bridge was closed in April 1972 and a new three-span steel rigid-frame bridge was built by Conn Construction Company for, using COR-TEN weathering steel.[9] The replacement bridge, designed by the firm of Richardson, Gordon and Associates (founded by George S. Richardson), opened on June 1, 1973,[10] and was presented with a Prize Bridge award for the medium-span, high-clearance category by the American Institute of Steel Construction in 1974.[11] Arthur W. Hedgren Jr. was chief design engineer and entered his design in the James F. Lincoln Arc Welding Foundation contest. Hedgren received a cash prize award and a summary of his ideas on this bridge design was published in a collection of winners.[12] The Lincoln Electric Company had created the James F. Lincoln Arc Welding Foundation to share knowledge about welding.

The bridge used two welded steel girders, supported at each end on reinforced concrete caps poured atop stone masonry abutments; the deck was supported by welded steel floor beams and rolled steel stringers. The rigid frame supports were inclined welded steel legs resting on reinforced concrete thrust blocks. The structural steel in the bridge and its inclined supports was not coated, as the weathering steel used was designed to develop a protective patina over time.

Prior to its collapse in 2022, the 446.9adj=midNaNadj=mid replacement bridge had been listed by the National Bridge Inventory as being in poor condition since September 2011.[13] The posted weight limit of the bridge was [14] and it carried more than 14,000 vehicles per day, with a posted speed limit of . The bridge was inspected most recently on September 19, 2021,[15] and the last inspection report was released in May 2022.[16]

In December 2018, Greg Kochanski, a software engineer who frequently walked beneath the bridge, tweeted a photo he took at the base of the bridge.[17] He expressed concern to the city that one of the original X-shaped cross braces on a bridge pier had corroded and severed where the pier met the ravine. He had privately observed the bridge supports were "well rusted, which he presumed was because of a drainage problem where melting ice and snow with salt from maintenance was draining down onto the beams". Kochanski observed in his tweet that tensioned cables already had been installed to replace the function of the cross-bracing. The city's 3-1-1 system opened a tracking ticket three days later;[18] a few weeks after the ticket was opened, it was closed and the corroded cross brace was removed. Kochanski's tweet went viral following the bridge's collapse.[19]

The steel cables had been installed in 2009; the 2021 inspection report noted "the cables were retightened in 2014 and are in good shape and are tight". A professor at the University of Pittsburgh faulted the use of the cables to replace the cross-braces, saying that officials "overestimated the contribution of the steel cable that was installed."[16]

Collapse

On January 28, 2022, at 6:39 a.m. EST, the Fern Hollow Bridge collapsed.[1] [20] Nearby residents reported hearing a loud boom and a whooshing noise around 6:35–6:40 a.m. Many credited the early morning time of collapse for the lack of fatalities, as the bridge was a route for many school buses, PRT buses, and commuters to work.[21] Pittsburgh Bureau of Fire Chief Darryl Jones said it was very fortunate the collapse occurred before the morning rush hour. The bridge was blanketed with snow from an overnight storm that had passed through the area.

Five vehicles were on the bridge when it collapsed, including a Pittsburgh Regional Transit articulated bus built by New Flyer in 2013. Another passenger vehicle drove off the eastern bridge abutment after the collapse and came to rest on its roof. At least 10 people were injured; three were taken to hospitals by ambulances. None of the injuries appeared to be life threatening. Some first responders rappelled about into the ravine, while others formed a human chain to rescue victims.[1] According to a law enforcement official, a passing jogger helped to rescue some of the motorists. The count of ten injured included some first responders who slipped and fell during the rescue operation.[22] The initial rescue effort was completed by 8:30 a.m. EST while emergency personnel continued to check under the wreckage for any trapped victims;[1] none were found.[23] A crane erected at Forbes and Briarcliff was used to retrieve the wrecked vehicles, and the bus (22 tons) was lifted from the site on January 31.[24] [25]

Under the road deck, the bridge carried a 16 inch (41 cm) natural gas pipeline, which severed in the collapse. Local residents were evacuated from their homes in response to reports of a "massive leak" and strong scent of natural gas. Officials shut down the gas lines in the area within a half-hour of the collapse.[26]

The bus, PRT fleet number 3309,[27] was operating route 61B outbound from downtown Pittsburgh (eastbound), and had nearly reached the east end before the bridge began to collapse. Driver Daryl Luciani later reported "the bus was bouncing and shaking" during the event.[28] After the collapse, first responders placed a ladder by the bus door, which Luciani and the two passengers aboard used to descend to the floor of the valley before walking up to Forbes.[29]

Political response

President Joe Biden had been scheduled to visit Pittsburgh on January 28 to speak about infrastructure at Carnegie Mellon University's Mill 19.[30] After learning about the collapse, White House press secretary Jen Psaki confirmed via Twitter that Biden would continue with his planned speech to promote the Infrastructure Investment and Jobs Act.[31] Biden visited the collapsed bridge at approximately 1:30 p.m., before his scheduled speech, and told reporters that he intended to direct funding to repair all 43,000 bridges in the U.S.[32] [33]

Biden was accompanied by multiple Pennsylvania politicians, including Mayor Ed Gainey, Allegheny County Executive Rich Fitzgerald, Governor Tom Wolf, Lieutenant Governor John Fetterman, U.S. Senator Bob Casey Jr., U.S. Representatives Conor Lamb and Mike Doyle, State Senator Jay Costa, and State Representative Dan Frankel. Wolf declared a state of disaster on January 28.[34]

Investigation

Shortly after the collapse, the National Transportation Safety Board announced it was sending a team led by Chair Jennifer Homendy to investigate the cause.[35] [36] According to Homendy, the investigation will take 12 to 18 months to complete; the team began gathering evidence after their arrival on January 28.[37] In a January 29 press conference held after the first complete day on-site, Homendy stated a preliminary report would be available in approximately 10 days, but the final report would require "a long, technical investigation" reviewing bridge inspection reports and maintenance records, video (from local businesses and the PRT bus), traffic counts, weight requirements, and road treatments.[38]

The preliminary report was released on February 7.[39] The collapse apparently initiated at the west end of the structure.[39] Surveillance video recovered from the bus showed the bridge had already fallen off the western abutment when the eastern expansion joint began to separate.[40] No primary fractures were found in the critical areas of the welded steel girders.[39] PennDOT ordered reviews of structural adequacy for five bridges with similar rigid K frame designs immediately; the five bridges (Canon-McMillan Alumni Bridge in North Strabane, Shenango Road Bridge in Beaver, Philip J. Fahy Memorial Bridge in Bethlehem, McCallum Street Bridge in Philadelphia, and Murray Avenue Bridge over Beechwood Blvd in Pittsburgh) were found to be in "fair" condition at their last inspections.[41]

The city briefly made an observation site available, but closed it by February 2,[42] [43] as the reconstruction effort began.[44]

In November 2023, victims took the city to court over access to bridge maintenance records.[45] The 2023 NTSB report concluded that a lack of periodic maintenance by the city led to clogged drains that caused corrosion, a contributing factor for the collapse; documents also questioned PennDOT's bridge inspection procedures.[46]

On February 21, 2024, the NTSB released its final report, faulting both city and state inspection processes for lack of required maintenance, repairs, and eventual bridge closure.[47] [48] Lawyers for injured parties reaffirmed their commitment to sue the city and other responsible parties for damages.[49]

Third bridge

The replacement bridge was designed by HDR, Inc. and constructed by Swank Construction of New Kensington; the contracts were awarded without bidding due to the emergency declaration and prior history with PennDOT.[50] Federal funds of $25.3 million were allocated for design and construction from the Federal Highway Administration's National Highway Performance Program, which in turn was funded by the Infrastructure Investment and Jobs Act of 2021.[51] During the first weekend in February, Swank moved demolition equipment to the site in preparation for removing the rubble. Building a new rigid K-frame bridge was unlikely, as the lead time for the steel required was more than 18 months.[52] The replacement bridge was designed and built in sections; once HDR released the design for a section, Swank built it while HDR designed the next section.[50]

On March 8, PennDOT announced that construction of the replacement bridge was planned to start in late April 2022.[53] The replacement bridge is a three-span continuous composite pre-stressed concrete I-beam with integral abutments. It carries four vehicle lanes, each wide, flanked by wide shoulders. The north side of the bridge has a wide sidewalk, while the south side has a wide shared-use path.[54] [55] The overall width is .[56] After viewing the proposed design, the Pittsburgh Art Commission called it "very similar to any highway overpass" and urged Mayor Gainey and Governor Wolf to pause the design, despite its role as "an important connection ... [that] really needs to be [rebuilt] with speed" as "the aesthetics of the bridge cannot be ignored."[57] City Controller Michael Lamb and Councilman Corey O'Connor joined the call to reconsider the initial design. Lamb added "Unfortunately, the initial images reflect a bridge that does not match the now-collapsed bridge in terms of space for people on non-motor vehicles, nor does it match the aesthetic of Frick Park or the adjacent neighborhoods."[58]

Construction of the replacement bridge began on May 9, 2022, marked by drilling for caissons and concrete pouring.[59] [60] By July 25, the support piers had been completed and the first prestressed concrete beams had arrived on-site, where they were lifted into place.[61] The replacement bridge was structurally complete by December 2022,[62] [63] and a ribbon-cutting for the new bridge was held on December 20, 2022.[64] The bridge opened to vehicular traffic around 1:30pm on December 21, 2022 with a single lane in each direction along with a physically separate combined pedestrian/bike lane.[65]

Work continued into Spring 2023 to complete the full bridge design including two lanes of vehicular traffic in each direction, a pedestrian-only sidewalk, and restored trail access under the bridge.[56] On June 12, 2023, the bridge was again closed so that crews could finish various elements of the bridge, including more permanent paving and sidewalks.[66] The bridge officially reopened on July 7, 2023.[67]

External links

Collapse

Data

Investigation

Notes and References

  1. News: Pittsburgh bridge collapse injures 10 on day Biden to visit city to talk infrastructure . Bella . Timothy . Sullivan . Sean . Duncan . Ian . The Washington Post . January 28, 2022 . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128130621/https://www.washingtonpost.com/nation/2022/01/28/pittsburgh-bridge-collapse/ . live.
  2. Wingate . Charles Frederick . February 15, 1902 . The Fern Hollow Highway Arch Bridge (Part 1) . The Engineering Record, Building Record and Sanitary Engineer . 45 . 7 . 156–158 . University of Chicago.
  3. Book: Wilson, Todd . Pittsburgh's Bridges . Arcadia Publishing Incorporated . 2015 . 9781439653890 . Charleston, South Carolina . 77.
  4. Wingate . Charles Frederick . February 22, 1902 . The Fern Hollow Highway Arch Bridge (Part 2) . The Engineering Record, Building Record and Sanitary Engineer . 45 . 8 . 170–171 . University of Chicago . January 28, 2022 . January 30, 2022 . https://web.archive.org/web/20220130015221/https://www.google.com/books/edition/The_Engineering_Record_Building_Record_a/x941AQAAMAAJ?hl=en&gbpv=1&pg=PA170 . live.
  5. A Steel Arch Highway Bridge At Pittsburgh, Pa. . Municipal Engineering . 96–97 . XXXI . 2 . August 1906 . January 28, 2022 . January 30, 2022 . https://web.archive.org/web/20220130015302/https://www.google.com/books/edition/Municipal_Engineering/rl5AAQAAMAAJ?hl=en&gbpv=1&pg=PA96 . live.
  6. News: 60-Ft. Leap Off Bridge Survived by Divorcee . March 10, 1958 . Pittsburgh Post-Gazette . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128185342/https://news.google.com/newspapers?id=HMZaAAAAIBAJ&sjid=42sDAAAAIBAJ&pg=4044,1153227 . live.
  7. News: Girl's Plunge To Death Ends Wedding Spat . January 6, 1958 . Pittsburgh Post-Gazette . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128190520/https://www.newspapers.com/clip/75204748/the-pittsburgh-press/ . live.
  8. News: Road Work to Limit Forbes Ave. Traffic . February 17, 1969 . . January 28, 2022 . January 30, 2022 . https://web.archive.org/web/20220130015221/https://news.google.com/newspapers?id=jcYwAAAAIBAJ&sjid=_WwDAAAAIBAJ&pg=4541%2C2415373 . live.
  9. News: Fern Hollow Bridge Job Is Delayed . November 14, 1972 . Pittsburgh Post-Gazette . January 28, 2022 . January 30, 2022 . https://web.archive.org/web/20220130015222/https://news.google.com/newspapers?id=Gp1RAAAAIBAJ&sjid=w2wDAAAAIBAJ&pg=4458%2C1999446 . live.
  10. News: It's Coming Friday! . May 30, 1973 . Pittsburgh Post-Gazette . January 28, 2022 . January 30, 2022 . https://web.archive.org/web/20220130015222/https://news.google.com/newspapers?id=fZxRAAAAIBAJ&sjid=CW0DAAAAIBAJ&pg=3890%2C4531305 . live.
  11. Web site: Prize Bridges/1974 . American Institute of Steel Construction . January 28, 2022 . May 3, 2017 . https://web.archive.org/web/20170503175831/https://www.aisc.org/globalassets/nsba/prize-bridge-brochures/1974prizebridgebrochure.pdf#page=7 . live.
  12. Welded Rigid Frame Bridge Replaces Deteriorated Seventy-Year-Old Span . Hedgren Jr. . Arthur W. . Richardson, Gordon & Associates . IV . 1980 . Modern Welded Structures . James F. Lincoln Arc Welding Foundation . A6–A8 . 4 February 2022.
  13. Web site: FORBES AVENUE over 9 MILE RUN & FERN HOLLOW . BridgeReports.com . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128204859/https://bridgereports.com/1456104 . live.
  14. News: 10 People Escape Serious Injury in Forbes Avenue Bridge collapse . Gratzinger . Ollie . Linn . Virginia . Cook . Richard . January 28, 2022 . Pittsburgh Magazine . 28 January 2022 . January 29, 2022 . https://web.archive.org/web/20220129002042/https://www.pittsburghmagazine.com/its-a-miracle-no-one-was-seriously-hurt-or-killed-in-forbes-avenue-bridge-collapse/ . live.
  15. News: Bloomberg – Bridge in 'Poor' Shape Was Checked Four Months Before Collapse . Niquette . Mark . Korte . Gregory . limited . 2022-01-29 . Bloomberg . January 28, 2022 . January 29, 2022 . https://web.archive.org/web/20220129091700/https://www.bloomberg.com/news/articles/2022-01-28/collapsed-pittsburgh-bridge-one-of-thousands-in-poor-condition . live.
  16. News: Report finds Fern Hollow Bridge appeared to have had 'major decay' just months before collapse . Sheehan . Andy . May 20, 2022 . CBS Pittsburgh . 10 August 2022.
  17. 1078885655634157569 . gpk320 . Greg . Kochanski . @Pgh311 I hope someone is keeping an eye on the underside of the Forbes Avenue bridge over Frick Park? One of the big "X" beams is rusted through entirely (and, yes, I see the cables, so it's probably not a crisis)..
  18. 1079725473947635714 . Pgh311 . Service Request #307260 has been created. https://pittsburghpa.qscend.com/311/request/view/?id=ea13511a408a4282815637644fd5a13a.
  19. News: Hamill . Sean D. . Pittsburgh man's 2018 photo shows rusted support under bridge that collapsed in Frick Park . January 28, 2022 . . en . January 28, 2022 . https://web.archive.org/web/20220128185352/https://www.post-gazette.com/local/city/2022/01/28/pittsburgh-bridge-collapse-2018-photo-point-breeze-frick-park/stories/202201280107 . live.
  20. Web site: Rittmeyer . Brian C. . Guza . Megan . Cato . Jason . January 28, 2022 . 10 injured in bridge collapse in Pittsburgh's Frick Park . January 28, 2022 . . en-US . January 28, 2022 . https://web.archive.org/web/20220128141635/https://triblive.com/local/frick-park-bridge-collapses-natural-gas-smell-in-area/ . live.
  21. Web site: Damp . Patrick . January 28, 2022 . 'It Sounded Like A Huge Snowplow:' Neighbors Recall Sights And Sounds From Pittsburgh Bridge Collapse . January 28, 2022 . en-US . January 28, 2022 . https://web.archive.org/web/20220128215447/https://pittsburgh.cbslocal.com/2022/01/28/neighbors-recall-bridge-collapse-frick-park/ . live.
  22. Web site: Fieldstadt . Elisha . January 28, 2022 . 10 people injured after snow-covered bridge collapses in Pittsburgh . January 28, 2022 . NBC News . en . January 28, 2022 . https://web.archive.org/web/20220128145240/https://www.nbcnews.com/news/us-news/pittsburgh-bridge-collapses-ahead-bidens-visit-talk-infrastructure-rcna13934 . live.
  23. News: Bridge collapse: Family of victims share story . January 29, 2022 . WDTV 5 . Wadas . Amy . 30 January 2022.
  24. News: The loss of the Fern Hollow Bridge means a scramble for alternate routes . Krauss . Margaret J. . Schneider . Sarah . January 30, 2022 . WESA 90.5 Pittsburgh NPR . 30 January 2022.
  25. News: Pittsburgh Bridge Collapse: Port Authority Bus Lifted Out Of Frick Park Ravine . Hoffman . Chris . January 31, 2022 . KDKA 2 CBS Pittsburgh . 31 January 2022.
  26. News: Lucey . Omar . Abdel-Baqui . Catherine . January 28, 2022 . Pittsburgh Bridge Collapses Near Frick Park Ahead of Biden's Visit . en-US . Wall Street Journal . January 28, 2022 . 0099-9660 . January 28, 2022 . https://web.archive.org/web/20220128152749/https://www.wsj.com/articles/pittsburgh-bridge-collapse-frick-park-11643379723 . live.
  27. News: Pittsburgh bridge collapse: hear the chilling radio calls for help . Kilmer . Liz . January 28, 2022 . WPXI-TV 11 . 31 January 2022.
  28. News: Driver of Port Authority bus caught up in bridge collapse talks about experience . Cipriani . Marcie . January 28, 2022 . WTAE Action News 4 . 29 January 2022 . January 29, 2022 . https://web.archive.org/web/20220129065112/https://www.wtae.com/article/bus-driver-pittsburgh-bridge-collapse-speaks/38925562 . live.
  29. News: 'I could just feel it': PAT bus driver says he knew Pittsburgh bridge was collapsing beneath him . Dawson . Jim . WPXI 11 . 30 January 2022.
  30. News: What to expect from President Biden's Pittsburgh visit . Deto . Ryan . January 27, 2022 . Trib Total Media . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128005311/https://triblive.com/news/politics-election/what-to-expect-from-president-bidens-pittsburgh-visit/ . live.
  31. News: Deto . Ryan . Biden visit to Pittsburgh still on following bridge collapse . January 28, 2022 . Pittsburgh Tribune-Review . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128143634/https://triblive.com/local/biden-visit-to-pittsburgh-still-on-following-bridge-collapse/ . live.
  32. News: Pittsburgh bridge collapses, President Biden visits site . January 28, 2022 . WTAE Pittsburgh Action News 4 . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128190751/https://www.wtae.com/article/pittsburgh-bridge-collapse/38926079 . live.
  33. Web site: Remarks by President Biden After Visiting the Site of The Collapsed Fern Hollow Bridge . January 28, 2022 . The White House . January 29, 2022 . January 28, 2022 . https://web.archive.org/web/20220128212504/https://www.whitehouse.gov/briefing-room/speeches-remarks/2022/01/28/remarks-by-president-biden-after-visiting-the-site-of-the-collapsed-fern-hollow-bridge/ . live.
  34. Gov. Wolf Declares Disaster Following Pittsburgh Bridge Collapse . January 28, 2022 . Governor of Pennsylvania . 29 January 2022 . January 29, 2022 . https://web.archive.org/web/20220129125659/https://www.governor.pa.gov/newsroom/gov-wolf-declares-disaster-following-pittsburgh-bridge-collapse/ . live.
  35. News: 'A boom, then a monster sound': 10 hurt after bridge over Pittsburgh's Frick Park collapses . Blazina . Ed . Bunch . Jesse . Goldstein . Andrew . Mamula . Kris B. . Routh . Julian . Stinelli . Mick . Strasburg . Stephanie . January 28, 2022 . Pittsburgh Post-Gazette . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128124028/https://www.post-gazette.com/local/city/2022/01/28/pittsburgh-bridge-collapse-forbes-braddock-avenue-point-breeze-squirrel-hill/stories/202201280075 . live.
  36. 1487089371593461763 . NTSB_Newsroom . January 28, 2022 . BREAKING NEWS: NTSB launching go-team to Pittsburgh bridge collapse. Chair Jennifer Homendy will be board member on scene. Arrival time this afternoon. Monitor Twitter @ntsb_newsroom for updates..
  37. News: Bridge collapses in Frick Park, hours before Biden arrives in Pittsburgh to discuss infrastructure . Krauss . Margaret J. . Doyle . Patrick . Zenkevich . Julia . Schneider . Sarah . January 28, 2022 . 90.5 WESA Pittsburgh NPR . 29 January 2022 . January 28, 2022 . https://web.archive.org/web/20220128205413/https://www.wesa.fm/2022-01-28/bridge-collapses-in-frick-park . live.
  38. News: NTSB Chair: Fern Hollow Bridge damage 'takes your breath away' . Schneider . Sarah . January 29, 2022 . 90.5 WESA Pittsburgh NPR . 30 January 2022.
  39. Web site: Bridge Collapse Accident No. HWY22MH003 . National Transportation Safety Board . January 28, 2022 . January 28, 2022 . https://web.archive.org/web/20220128222758/https://www.ntsb.gov/investigations/Pages/HWY22MH003.aspx . live.
  40. NTSB Issues Investigative Update for Pittsburgh Bridge Collapse . May 5, 2022 . National Transportation Safety Board . 19 September 2023.
  41. News: PennDOT to reinspect bridges with similar design as Fern Hollow Bridge . Felton . Julia . February 1, 2022 . Pittsburgh Tribune . 14 February 2022.
  42. News: There's now an observation area at the Fern Hollow Bridg ecollapse site . Koscinski . Kiley . January 31, 2022 . 90.5 WESA Pittsburgh NPR . 28 February 2022.
  43. News: Fern Hollow Bridge collapse viewing area closed 'indefinitely' just 2 days after opening . Guza . Megan . February 2, 2022 . Pittsburgh Tribune . 28 February 2022.
  44. Web site: Gratzinger . Ollie . Timeline for Rebuilding Fern Hollow Bridge Still Uncertain, but Work is Underway . . 28 February 2022 . 11 February 2022.
  45. Web site: 2023-11-28 . Victims fighting in court for answers about Fern Hollow Bridge collapse cause . 2024-01-06 . WPXI . en.
  46. Web site: Osdol . Paul Van . 2024-01-05 . NTSB documents released in bridge collapse investigation show city of Pittsburgh failed to do proper maintenance . 2024-01-06 . WTAE . en.
  47. Web site: Osdol . Paul Van . 2024-02-21 . NTSB: Fern Hollow Bridge should have been closed years before collapse . 2024-02-22 . WTAE . en.
  48. Web site: 2024-02-22 . ‘Should never have happened.’ Investigators fault Pittsburgh for bridge collapse and reveal what caused it . 2024-02-22 . The Morning Call . en-US.
  49. Web site: Rodriguez . Yazmin . 2024-02-22 . Lawyers in Fern Hollow Bridge collapse going after the city . 2024-02-22 . WTAE . en.
  50. News: PennDOT selects team to replace Fern Hollow Bridge, says some demolition could start this weekend . Blazina . Ed . February 4, 2022 . Pittsburgh Post-Gazette . subscription . February 28, 2022.
  51. News: Emergency contract to allow for design work to begin on Fern Hollow Bridge replacement . Felton . Julia . February 4, 2022 . Pittsburgh Tribune . February 28, 2022.
  52. News: What To Expect As Demolition, Rebuilding Process Begins At Site Of Fern Hollow Bridge Collapse . Shumway . John . February 7, 2022 . KDKA 2, CBS Pittsburgh . February 28, 2022.
  53. News: Fern Hollow Bridge construction expected to begin in April . Deto . Ryan . March 8, 2022 . Pittsburgh Tribune . May 4, 2022.
  54. Fern Hollow Bridge Design, Construction Advance in Pittsburgh . March 8, 2022 . Pennsylvania Department of Transportation . May 4, 2022.
  55. News: Gainey sees no need to change design of proposed Fern Hollow Bridge . subscription . Blazina . Ed . March 11, 2022 . Pittsburgh Post-Gazette . May 4, 2022.
  56. Web site: Fern Hollow Bridge Project . Pennsylvania Department of Transportation . May 4, 2022.
  57. News: 'It could be a long-term mistake': Some groups want more time to design Fern Hollow's replacement . Krauss . Margaret J. . March 3, 2022 . 90.5 WESA . May 4, 2022.
  58. News: Some Pittsburgh officials question new Fern Hollow Bridge design . subscription . Blazina . Ed . March 11, 2022 . Pittsburgh Post-Gazette . May 4, 2022.
  59. News: Construction to begin this week on Fern Hollow Bridge replacement . Blazina . Ed . May 9, 2022 . Pittsburgh Post-Gazette . subscription . August 10, 2022.
  60. Web site: Felton . Julia . Construction of new Fern Hollow Bridge in Pittsburgh's Frick Park begins . Pittsburgh Tribune . May 10, 2022 . December 21, 2022.
  61. News: First support beams for Fern Hollow Bridge Replacement arrive in Squirrel Hill . Kirkland . Talia . July 25, 2022 . WPXI-TV 11 News . August 10, 2022.
  62. Web site: Mamula . Kris B. . Fern Hollow Bridge remake nears completion, with reopening expected within a week . Pittsburgh Post-Gazette . December 20, 2022 . December 21, 2022.
  63. Web site: Felton . Julia . Completed Fern Hollow Bridge unveiled in advance of Friday reopening . Pittsburgh Tribune . December 21, 2022 . December 21, 2022.
  64. Web site: Officials cut the ribbon on the rebuilt Fern Hollow Bridge, less than a year after its collapse . 90.5 WESA . December 21, 2022 . December 21, 2022.
  65. Web site: Felton . Julia . Pittsburgh's new Fern Hollow Bridge reopens to traffic . Pittsburgh Tribune . December 22, 2022 . December 22, 2022.
  66. https://www.wtae.com/article/fern-hollow-bridge-to-close-for-4-weeks/44154300
  67. Web site: Derose . Christopher . Fern Hollow Bridge reopens after final touches – CBS Pittsburgh . . September 19, 2023 . 8 July 2023.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Fern Hollow Bridge".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.