Duck Hollow Bridges

Posted on September 18, 2025 by Carolyn Ristau

Duck Hollow is a mini neighborhood where Frick Park’s Nine Mile Run meets the Monongahela River in Pittsburgh. A handful of houses sit in the Hollow accessible only by an old one-lane bridge on a small spur of Second Avenue or the new bridge on McFarren Street that opened in 2020 (though it was only 2 years old at the time of the Bridge Report and presumably doesn’t see much traffic, it only received an overall grade of “good”). The houses of Duck Hollow are separated from the river by the railroad that crosses Nine Mile Run on the bridge above Second Avenue. These photos are from a walk my COVID-pod and I took of Frick Park in Fall 2020.

Buffalo Bridges: Canalside

Posted on June 19, 2025 by Carolyn Ristau

There are several pedestrian-only bridges at Canalside, Buffalo. They pass over the end of the Erie Canal, a portion of which has been paved over with a skating rink. When I was there, one of these bridges was closed due to construction and I couldn’t figure out how to get to another one. I did walk over two others of these pedestrian bridges – one over the paved portion and one over the water portion.

Bridge Collapse (PGH): Three Years Later

Posted on January 29, 2025 by Carolyn Ristau

Three years ago, Pittsburgh’s Fern Hollow Bridge collapsed on a cold and icy morning. Since then, I have periodically checked in on the status of the new bridge, the fallout from the collapse including the Mayor’s new Commission on Infrastructure Asset Reporting and Investment, and the condition of other bridges, particularly those closed for safety reasons since the Fern Hollow Bridge collapsed.

At my last check-in one year ago, the National Transportation Safety Board’s investigation was still on-going with the latest update on their website a year old. The investigation wrapped up shortly after and the NTSB’s final report was issued in March 2024 (WTAE, March 22, 2024). Unsurprisingly, the report found that the City’s failure to act on the maintenance and repair recommendations from years of inspections led to the structural failure of the bridge. Specifically:

On Friday, January 28, 2022, about 6:37 a.m. eastern standard time, the Fern Hollow Bridge, which carried Forbes Avenue over the north side of Frick Park in Pittsburgh, Allegheny County, Pennsylvania, experienced a structural failure. As a result, the 447-foot-long bridge fell about 100 feet into the park below. The collapse began when the transverse tie plate on the southwest bridge leg failed due to extensive corrosion and section loss. The corrosion and section loss resulted from clogged drains that caused water to run down bridge legs and accumulate along with debris at the bottom of the legs, which prevented the development of a protective rust layer or patina. Although repeated maintenance and repair recommendations were documented in many inspection reports, the City of Pittsburgh failed to act on them, leading to the deterioration of the fracture-critical transverse tie plate and the structural failure of the bridge.
NTSB: Collapse of the Fern Hollow Bridge

News

Below are the news updates on the Fern Hollow Bridge and other bridge maintenance and replacement efforts in Pittsburgh and Allegheny County.

The National Transportation Safety Board’s investigation into the collapse of the Fern Hollow Bridge is completed.
Immediately after the Fern Hollow Bridge collapsed, the City created a Commission on Infrastructure Asset Reporting and Investment. However, it took Mayor Gainey about 18 months to nominate any commissioners and another 5 months for the commission to have its first meeting on December 5, 2023. Despite finally existing, it still hasn’t been added yet to the city’s website listing all Boards and Commissions. It does have an official city website though. The first report from the Commission to City Council was issued on June 5, 2024. In the cover letter, the Commissioners acknowledge that they are charged with reporting to council at least twice a year.
The Charles Anderson Bridge was immediately closed to vehicular traffic on February 1, 2023. On November 4, 2024, the bridge was closed to bicycle and pedestrian traffic as construction was finally underway for rehabilitation of the bridge (the process started in 2019). The Panther Hollow Overpass is also being improved while the traffic is detoured. (Pittsburgh Engage project page)
Pittsburgh’s Swindell Bridge, which closed initially from July to September 2022 due to falling debris. The expectation was that repairs that summer would enable the bridge to fully reopen to traffic. Instead the latest repairs seem to have uncovered more issues. The bridge will eventually undergo a full rehabilitation, which will require another closure during construction. However, that will not be for some time as the bridge is still in the preliminary design phase. (Pittsburgh Engage page)
The “complete overhaul” of the South Negley Avenue Bridge announced in 2022 (CBS, February 25, 2022). The city still does not have a project page for this bridge, though both sidewalks have been closed for safety (Mayor’s Press Release, June 6, 2024; Mayor’s Press Release, June 17, 2024). The obvious deterioration on this bridge and lack of movement on repairs leaves the way open for speculation on whether we will have another bridge disaster in our city sooner rather than later.
Supply chain issues and now winter weather have delayed the completion of the new Davis Avenue Bridge. (Bridge Engage Page; Public Art Engage page)
Rehabilitation on the Swinburne Bridge remains on pause until after the Charles Anderson Bridge is reopened as the Swinburne Bridge is part of the detour route. (Pittsburgh Engage page)
Preliminary engineering remains ongoing for the rehabilitation of the 28th Street Bridge. (Pittsburgh Engage page)
Preliminary engineering has started for the California Avenue Bridge rehabilitation. (Pittsburgh Engage page)
While the number of “Engage pages” about Pittsburgh bridges has grown in the last year (full list below the map), it still does not align with all the bridges closed fully or partially. In addition to the bridges mentioned above, the most recent addition to the list of bridges with issues, but no Engage page is the Panther Hollow Bridge that closed to vehicles October 2024 due to the results of its most recent inspection (see 2024 Bridge Disasters Actual and Pending for more).
In national bridge news, Congress fully funded the reconstruction of the collapsed Francis Scott Key Bridge before the end of December (Governor Moore’s statement, December 21, 2024), contrary to my prediction on Funding Bridges (December 15, 2024).

Photos: Other Bridges

Historic Pittsburgh Bridge Disasters

According to Bob Regan’s 2006 book “The Bridges of Pittsburgh,” Pittsburgh is no stranger to bridge disasters:

1845 – The original Smithfield Street Bridge burned down
1851 – The 16th Street Bridge burned down
1865 – Two spans of the 16th Street Bridge was washed away in a flood
late 1880s – The 6th Street/St. Clair Street Bridge burned down
1903 – The Wabash Bridge collapsed during construction
1918 – The 16th Street Bridge burned down (again)
1921 – The 30th Street Bridge burned down
1927 – The Mount Washington Roadway Bridge collapsed during construction

Map of bridges discussed in the Bridge Collapse series:

Additional Resources:

Both PennDOT and the Federal Highway Administration have interactive maps of bridges for the state and country respective, and their inspection statuses. Pittsburgh now has the static Comprehensive Bridge Asset Management Program Report of the 147 bridges owned by the City of Pittsburgh.

Bridges in Pittsburgh with community engagement pages for pending rehabilitation or replacement projects:

Previous Fern Hollow Bridge Posts:

Two Year Update

Eighteen Month Update

2024 Bridge Disasters Actual and Pending

Posted on December 18, 2024 by Carolyn Ristau

Bridge accidents is a common theme this year. The most significant was the collapse of Baltimore’s Francis Scott Key Bridge in March 2024 after being struck by a malfunctioning container ship. However, other accidents happened to bridges in the Pittsburgh area. Weeks after Baltimore’s bridge collapse, the Sewickley Bridge, a few miles downriver from Pittsburgh, closed for a day after being struck by runaway barges (WTAE, April 14, 2024). Then, in August, a dump truck struck an unused railroad bridge in Pittsburgh. The road underneath closed temporarily while the obsolete and now damaged bridge was removed. The adjacent, active railroad bridge remains. (WTAE, August 16, 2024)

Meanwhile, Pittsburgh continues to preemptively close bridges or restrict traffic to reduce the chances of another bridge collapse. The most recent of these is the full closure of Panther Hollow Bridge announced October 19, 2024, with immediate effect. It is called a temporary closure while the City of Pittsburgh figures out what it needs to do for the bridge. (Mayor’s Press Release, October 19, 2024) Other recent “temporary closures” of Pittsburgh bridges have turned into sporadic periods of closure and opening (Swindell Bridge) or a years-long closure while funding is found and repairs are implemented (Charles Anderson Bridge).

Another common restriction we are seeing in Pittsburgh bridges is sidewalk closures while vehicular traffic remains unaffected. Pittsburgh’s South Negley Avenue bridge is one of the bridges in town that is poised as a pending disaster. In acknowledging the structural issues of this bridge, the west sidewalk was closed in 2022. However, I noticed that by July 2023, the barriers on that sidewalk were pushed aside and it wasn’t clear if that was an official move or if pedestrians had taken matters into their own hands. Then, in June 2024, first the eastern sidewalk was closed with a temporary protected pedestrian pathway installed in the car lane (Mayor’s Press Release, June 6, 2024) and then, a week later, the western sidewalk was again closed (Mayor’s Press Release, June 17, 2024). Why this “safety” measure is helpful is beyond me as this bridge has been earmarked for replacement for years pending funding and access issues. Also, the Smithfield Street Bridge sidewalk always has rusted out holes showing the river flowing below that eventually get patched without closing the sidewalk.

Funding Bridges

Posted on December 15, 2024 by Carolyn Ristau

Bridges are a vital connectors that enable us to move around as we live our lives. Frequently, we don’t even realize there’s a bridge there…at least not until there’s a bridge disaster. Over the last few years, there have been several bridge disasters, some due to accidents, like the collapse of Baltimore’s Francis Scott Key Bridge in March 2024 after being struck by a malfunctioning container ship, and some due to deferred maintenance, like the collapse of Pittsburgh’s Fern Hollow Bridge on an icy, cold morning in January 2022.

We have seen recently that when there is motivation, the missing links caused by bridge disasters can be repaired in record time. Pittsburgh’s Fern Hollow Bridge was completely rebuilt and opened to traffic 11 months after collapsing, instead of the usual multi-year process to design and build a new bridge. In Philadelphia, when an elevated section of I-95 collapsed after an accident in 2023, the repaired section reopened to traffic 12 days later, compared to 26 days for a similar situation in Oakland, CA. (PBS News, June 23, 2023)

Despite President Biden’s repeated request to Congress to expedite funds to replace Baltimore’s Francis Scott Key Bridge, Republicans in Congress are possibly motivated to delay so that President-elect Trump will get the credit for rebuilding this crucial transportation link. (Fox News Baltimore, November 8, 2024; WCBM, November 8, 2024) Unfortunately, Trump does not have a good track record for funding bridges.

It can be easy to overlook during the buzz of election season that there is often a delay between when a law is signed or a policy adopted and when the effects of that law or policy are felt. Bridges encapsulate that well. The memorable moments are when a bridge closes or collapses (typically viewed negatively) and when a bridge reopens (typically viewed positively). The moment when funds are allocated, the moment enabling a bridge to reopen at a later date, is not often remembered.

For example, it was front page news when the new Greenfield Bridge reopened in 2017, when Trump was President, but the funding that constructed the bridge was allocated when Obama was President. Similarly, the Charles Anderson Bridge has been closed to traffic for most of President Biden’s term in office, to the annoyance of many, but that is also when the funds were found to rehabilitate the bridge expanding the life of this historic bridge by decades. However, the reopening is projected to be in 2026, in the middle of Trump’s second term as President.

Assuming two years as the average time from funding to reopening on bridge reconstruction and rehabilitation projects, I pulled the Federal Highway Administration’s numbers for bridge construction and rehabilitation in Pittsburgh that would have been funded under the leadership of Presidents George W. Bush, Barack Obama, and Donald Trump. (FHWA InfoBridge) Given the delay between funding and completion, it is too early to measure the impact of funding under President Joseph Biden’s leadership.

Bush: 36 bridges total = 4.5 bridges per year

Obama: 76 bridges total = 9.5 bridges per year

Trump: 9 bridges total = 2.25 bridges per year

Bridge maintenance and repair rarely happens without support from federal funding. When the bipartisan infrastructure bill passed under President Biden’s leadership runs out of funds, or those funds get diverted to Project 2025, I am skeptical that new funding for bridges will be found under the leadership of President-elect Trump. Therefore, I expect more bridge disasters or, at the very least, more indefinite bridge closures in the coming years.

Walkway Over the Hudson

Posted on November 15, 2024 by Carolyn Ristau

I don’t remember how I first heard about the Walkway Over the Hudson, but it was several years before I developed the habit of walking bridges. Even at that time it sounded like a cool place to check out. Once I became a bridge-walker, it became a must-experience site. Over a decade later, I finally walked the Walkway Over the Hudson.

The Walkway Over the Hudson crosses the Hudson River at Poughkeepsie, NY. It opened in 1889 as a railroad bridge. It closed in 1974 after being damaged by fire and reopened as a renovated pedestrian bridge in 2009. It is both a National Historic Civil Engineering Landmark and on the National Register of Historic Places. At 1.28 miles it claims to be the longest pedestrian bridge in the world.

It is also 212 feet above ground or river level. In discussing my experience of climbing to the top of St. Paul’s Cathedral in London, I glossed over the fact that I almost didn’t reach the top due to my discomfort with heights and instead focused on the fact that claustrophobia almost prevented me from coming back down. Proportions and railing heights have a significant impact on whether I can manage heights. The Whispering Walk inside the base of the dome in St. Paul’s was too narrow and enclosed for me to handle the height above the floor (98 feet). The Walkway Over the Hudson, on the other hand, was quite wide having once carried two railroad tracks side-by-side. And so despite being more than twice as high up as the Whispering Walk, I did not experience much trouble with the height. I was more concerned about the possibility of the wind tearing my phone/camera out of my hand and over the edge.

Despite the potential damage that objects falling off the side of the bridge could cause, extra high barriers to prevent that are only located over the railroad tracks. As I’ve discussed in previous posts, some bridges have extra fencing only along portions of their walkways, typically over railroads and sometimes over automobile roads. The extra fencing on the Walkway Over the Hudson is from a time after it was common to curve the top, creating a cage-like feel, but before the need for extra height was incorporated into the design of the bridge itself.

There is no shade on a deck-truss bridge 212 feet off the ground. On a hot, July day, you feel the full force of the sun when taking such an exposed 1.28 mile walk starting at 11:30. If I hadn’t discovered that there was another bridge that I could walk across, I probably would have opted to take the shuttle back.

The Olympic Village

Posted on October 30, 2024 by Carolyn Ristau

Adrenaline is a powerful force. When I arrived in Vancouver in 2016, I bounded with energy despite only having slept 4 hours in the previous 36. After dropping my stuff off at my lodgings, I rented a bike and rode like a woman on a mission along the waterfront trail. Part of that mission was to burn off the adrenaline so that I would be able to sleep that night.

However, revisiting my photos and my recollections of this trip to write about the bridges and greenery, I’ve been haunted by the thought that there was an additional mission to that bike ride. I distinctly remember biking the trail along False Creek, but I have no photos from this excursion (the photo above is False Creek from Granville Bridge, nowhere near Olympic Village). Perhaps I was too focused on my mission? One line from my travel journal buried in a flurry of thoughts on urban design reminded me that the destination of that bike ride was the Olympic Village from when Vancouver hosted the 2010 Olympics.

In my journal reflecting on the city’ newer architecture that could have been anywhere, I wrote: “In biking along the coastal trail, there were several parts that I felt could have been Cardiff or London. For instance, the part around Yaletown felt like the Cardiff Wharf development, though this one melded into its surroundings on all sides unlike Cardiff’s which was just plopped there. The area around Olympic Village and parts also around Yaletown felt a lot like the part of London past the Tower Bridge on the southern shore.” (Photos of the area around Tower Bridge are below and, of course, the building that I remember as being what I probably was thinking of in Vancouver is not one I photographed.)

My interest in the Olympic Village came from the same place as my on-going interest in World Fairs and Urban Renewal. These are large-scale developments that cities pursue “for the greater good” to attract tourists and others outside their boundaries while ignoring or actively harming their residents. Despite the intent, the end result is often more harm than good. For example, the Olympics and World Fairs are typically promoted as events that will bring in extensive revenues to the city, but most lose money due to the large expenditures required to build the necessary facilities. A successful Fair or Olympics is the one that breaks even.

In my Comparative International Urbanism course in college, I wrote a paper on three large-scale redevelopments in London, including the Olympic Village from the 2012 summer games. I intended to visit the Olympic Village when I visited London that May, but I got distracted by bridge walking. The research I did for that paper on Olympic Villages highlighted the inequities inflicted on residents in the construction of these developments. Based on my paper, over 200 local businesses and nearly 1,000 residents were evicted for London’s Olympic Village.

While I can’t find my notes, I seem to recollect that researchers featured Vancouver as the city whose Olympic Village created the least harm for existing residents and most seamlessly integrated into city life after the games and athletes left. Something I definitely would have wanted to see while in Vancouver, but I was operating on too little sleep to take photos to prove I was there.

Cardiff Bay Wharf Development

London Tower Bridge Southern Shore

London Olympics

Bygone Bridges of Highland Park

Posted on July 12, 2024 by Carolyn Ristau

My primary day job this year involves spending lots of time with Pittsburgh archives, particularly maps. That was how I discovered that East Liberty used to have more bridges. Since then, I discovered that the Highland Park Bridge used to be in a completely different location, adjacent to the western end of Heth’s Run Bridge. The image above from the Pittsburgh Historic Maps, an online ArcGIS map viewer, shows the 1939 satellite images for the area with the former Highland Park Bridge to the left and the current Highland Park Bridge under construction on the right.

Once again, thanks to Historic Pittsburgh, I found photos of the former bridge. The first pair of photos below shows the Highland Park Bridge beyond the Heth’s Run Bridge, the older one looking west and the newer one looking east. The second pair of photos compares the Heth’s Run ravine in it’s original condition after being bridged to its restored condition after being filled in and then re-excavated. The third pair of photos compares the former and current Highland Park Bridges.

Photo sources:

Heth’s Run Bridge Photo: https://historicpittsburgh.org/islandora/object/pitt%3A715.262240.CP

Highland Park Bridge Photo: https://historicpittsburgh.org/islandora/object/pitt%3A1999.34.9

Chicago’s Other World’s Fair

Posted on June 21, 2024 by Carolyn Ristau

Unbeknownst to me at the time, on my aborted bike ride to the site of the White City in 2013, I rode right passed the site of Chicago’s other World’s Fair. The Century of Progress 1933 World’s Fair was located on what is now called Northerly Island. Adler Planetarium and Shedd Aquarium were the obligatory permanent museums opened in conjunction with or adjacent to the fair.

One of the interesting tidbits I’ve learned about this fair is that it used a rainbow of colors. Clearly, this was intended to be among the elements that would distinguish this fair from the previous one. However, it sounds to me more like Chicago was trying to imitate Buffalo’s Rainbow City, the 1901 World’s Fair.

My thanks to Zachary L. Brodt and his book From the Steel City to the White City: Western Pennsylvania & the World’s Columbian Exposition for helping me to realize that I can say I’ve visited four former US hosted World’s Fair sites as of May 2024.

Buffalo’s Rainbow City

Posted on June 15, 2024 by Carolyn Ristau

Having now been to two former World’s Fair sites, I felt compelled to round it out with a third. Weeks before COVID hit, I was in the planning phase for a trip to Buffalo when I discovered that they had held a World’s Fair in 1901. I had found my third site, though the visit was delayed several years from the fallout of COVID and life.

As I got off the bus at the end of a bridge over an expressway, I had moment of panic before seeing I was right next to the History Museum and a quiet residential neighborhood, just as I had intended. There were several parallels between this site and those I explored in San Francisco and Chicago, but the feel of the place was completely different. There was the characteristic lagoon, or in this case lake, surrounded by park, but the park and lake were designed by Frederick Law Olmsted long before the idea of the fair was born. Like Chicago, the remaining fair building(s) was used as a museum, and while the architecture is intended to inspire awe and perhaps intimidation, it is the normal awe and intimidation of the average temple to art or history seen in many cities and not the massive scale of San Francisco’s Palace. The park is also bisected by a road with dangerously fast traffic, but there are multiple safe pedestrian crossing points over and under (including the Whirly-Twirly Bridge). There was a Japanese Garden here as well, but it was installed decades after the fair and was illustrative of the fact that this site had a life before the fair and continues to have an on-going life after the fair.

The remainder of the fair site between the park and the railroad tracks where the fair had a station has been fully redeveloped. Over half of that area is now residential neighborhood(s) with a variety of housing types from modest single-family dwellings to large homes with security fencing and landscaping staff. (Passing these houses and taking photos, I again felt the potential for someone to approach and question my belonging and right to explore.) There were also two-family dwellings and apartments. I passed two schools, a former church, some industrial properties, a paddock, and a strip mall. One of the residential streets had a sign acknowledging the past as the site of the 1901 Pan American Exposition. Otherwise, I wouldn’t have know I was on the site of a former World’s Fair without having carefully studied the map of the fair beforehand. I felt as though I was in any other neighborhood of any other city that is flat and that has residents who have at least a little, though in many parts it was clear that the residents had a lot.

As I had unintentionally read about the World’s Fairs in San Francisco and Chicago before visiting those sites, I decided that I needed to intentionally read about Buffalo’s before going so that there would be some consistency in my approach. One of the points that Margaret Creighton reiterated in her book The Electrifying Fall of Rainbow City was that Buffalo was trying to outdo Chicago (they picked the Rainbow City theme and lighting scheme to be in direct contrast to Chicago’s White City). In the end, and certainly not helped by the fact that President McKinley was shot at the fair, Buffalo did not have the success they sought in receipts or in numbers of visitors.

Having now visited both Chicago and Buffalo’s fair sites, I would say that over 100 years later, Buffalo has had the greater long-term success on its fair site than Chicago. The entire area once covered by the fair is now, and has been for some time, an actively used location. From the park with a number of tourists and residents enjoying all the amenities (even in the middle of a Monday at the beginning of the school year) to the homes to the businesses, Buffalo’s fair site must by this point have long outstripped Chicago’s in number of visitors/residents/users and in tax revenue/receipts.