The Donora-Webster Bridge ober the Monongahela River in Washington County, Pennsylvania. Â Walking across the bridge during a bridgehunting tour in Pennslyvania, I was awed by the beauty of the structure as it stood at least 20 feet tall above the water. Its grey color matched the color of the landscape, which had a mixture of green vegetation, brown to light-colored houses, and a dark aqua color of the Monongahela River, as it meanders its way towards Pittsburgh to join the Allegheny River to form the Ohio River. This bridge had a unique design as all but one span consisted of a Parker through truss design. The lone span, which was also the center span, consisted of a Pennsylvania Petit design, with a span of almost 600 feet. And the portal bracings, the entrance to a through truss bridge, are different between the main span and the other four spans, but both were unique and worth looking at as a tourist. Sadly however, this bridge is slated for demolition within the next 3 years as structural concerns have prompted its closure. However, looking at the bridge more closely, one can assume that due to the fact that if a bridge could not carry vehicular traffic anymore that it would be at least converted to pedestrian and cyclar traffic, right?
Not in the eyes of the Pennsylvania Department of Transportation and the state legislation, as both agencies have been taking proactive steps towards demolishing and replacing any bridges that are 70 years of age and older as well as those considered structurally deficient, meaning that they are unable to handle the increasing amount of traffic on a daily basis. In the past 10 years, about 60% of the bridges that were built of iron and/or steel and belong into the aforementioned categories have met the wrecking ball with many more yet to come. Most of them were built using a truss or cantilever truss design (a description of the two can be found in the link in the education section of the front page). The hardest hit areas are in the western and northern sections of the state where these gems of American history are located in sparsely populated areas but are most prone to demolition. There 70% of the bridges have been lost since 2003. This includes not only simple span truss bridges with ornamental truss designs like the Kreitz Road Bridge in Crawford County and the Tunnelton Bridge in Indiana County (both in 2010), but also multiple span bridges such as the Ulster Bridge in Bradford County (2007) and the Shanley Road Bridge in Elk County (2004), and rarities, like the Foxburg Bridge in Clarion County (2008). And more are yet to come as the campaign to replace these rarities with sturdier structures will continue until every bridge has a new structure. Unfortunately, the structures that replace these unique bridges consist of mainly concrete bridges that are mudane and many times do not conform with the landscape provided by the communities they used to serve. And to add insult to injury, these multi-million dollar projects come at the cost of the common person’s billfold.
This alarming trend has led to a pair of questions that have to this day not been answered: 1. What factors are leading to this rapid demise of these historic bridges Â and 2. Are there measures that can be taken to halt this trend and preserve what is left to be preserved?
It is no secret that if one compares the US infrastructure to that of many countries in Europe (including Germany where the author is residing) that the quality of the infrastructure, in particular the bridges is far better in Europe than in America. In fact, recent reports by the American Society of Civil Engineers rated the American infrastructure as a grade D. The bridges were given a grade of a C, the second highest result behind waste treatment (with a C+). This means that despite improvements in the repairs and replacement of many structurally deficient bridges, there are still tens of thousands left to pay attention to. Of these, Pennsylvania leads the nation with as many as 6,000 structurally deficient bridges out of the 31,600 bridges that exist in the state, even though initiatives have been carried out by Governor Ed Rendell to invest as much as $500- 700 million annually in bridge projects. Pennsylvania has one of the most rigorous bridge inspection programs in the country where each bridge is inspected biannually, with the structurally deficient ones being examined more often to monitor any further deterioration. Bridges considered structurally deficient are closed and are either repaired or replaced at the earliest possible convenience. Unfortunately, many of the bridges affected by this thorough inspection happen to be truss and cantilever bridges whose average lifespan on the roadways can range from 60 years to 120 years. Despite attempts by PennDOT to market these bridges to interested parties, these attempts have failed to bear fruit and subsequentially they are replaced. This is in part because of the lack of financial resources and interest in purchasing the bridges, although the last bridge purchased in Pennsylvania- a pony truss bridge- was eventually relocated to neighboring Delaware, a deal that was finalized in May of this year. This rapid decline in historic bridges leads to the next question of the possibility of leaving the historic bridge to stand while the new structure built right next to it serves regular traffic. While such practices can be seen in places like Iowa, Tenessee, Michigan, and Texas (just to name a few), laws in Pennsylvania dating back to 1966 literally forbid such practices and puts the liability of such property on those interested in purchasing them, resulting in the withdrawl in the party’s interest in buying the historic bridge. This contributed greatly to the demise of many bridges affected, such as the Shanley Road, Tunnelton, and Ulster Bridges, respectively.
Despite attempts of cooperating between both sides of the spectrum, the issue of the historic bridges has become a focus of debate as many have taken sides and pointed fingers at each other. Those wanting to see the rest of the historic bridges saved have accused PennDOT of having poor preservation policies and historic bridge marketing practices, ranking it as the worst in the country. On the other side of the spectrum, legislators and PennDOT officials have attacked the historic bridge mitigation policies in connection with Section 106 of the Historic Preservation Act and the mandated environmental impact surveys claiming that they are delaying the replacement process. One Pennsylvania Senator, Barry Stout even went as far as retorting the historic bridge preservationists and stated that historic bridges are not meant for museum displays, while at the same time, claimed that the delays in replacing the bridges because of the Section 106 process is costing money and time and opposes such procedures. This was in response to two bridges that are slated for replacement in the next year, the Donora-Webster and the Chareloi-Monessen Bridges.
If there are dark sides to historic bridge preservation policies in Pennsylvania, there is almost a guarantee that there is a ray of light that might not only steer the course that has been taken by PennDOT and other agencies, but also bring the sides together to collaborate on this topic and save what is left of the historic bridges in Pennsylvania. Already, many large cities in the state have taken vast efforts to preserve and maintain their historic bridges not only to be used for recreational purposes but also for vehicular traffic. For instance, the 1860 Walnut Street Bridge in Northhampton County, the oldest surviving cast iron through truss bridge in the country, was reincorporated into a bike trail after years of rehabilitation and now serves as a link to Lehigh University. The Walnut Street Bridge over the Sushquehanna River in Harrisburg (the state’s capital) was convertedto pedestrian traffic and was even rebuilt after flooding took out the eastern spans in 2006. Many of Pittsburgh’s bridges have been refurbished and are now serving traffic again. This includes the Hot Metal Bridge over the Monogahela River, which used to be a a pair of railroad bridges before being converted into a roadway bridge for one span and a bike trail bridge for the span next to it.
The latest attempt at trying to preserve a historic bridge is converting it into a park. This is actually being done with the Quaker Bridge in Mercer County. Spearheaded by Nathan Clark, the 1898 bridge was bypassed by a new bridge in 2006. Despite some legal entanglements, Clark hopes to have sole possession of the bridge in which it will be converted to a park, providing the tourists with a splendid view of the Little Shenango River and a chance to do some picnicking on the Pratt through truss bridge. This bridge, together with the Meadville Bridge were the centerpieces of the Historic Bridge Conference, which took place this past August (for more information on the Meadville Bridge, please refer to the 11 October entry).
Despite these steps that are being taken, it is not enough to stem the number of historic bridges that are being replaced with many more yet to follow in the next five years. Part of the problem with bridges that are 70 years and older is that there is not enough money and resources to maintain them, thus many of the structures are left to decay. The bridge types that are hardest hit are the metal truss and cantilever bridges and those built using steel and/or iron, as the wear and tear, combined with the weather extremities and the usage of salt and other materials have led to the rust and corrosion of the truss parts to a point of beyond repair, thus resulting in the need to replace the bridges. This applies to all crossings including the Greensburg Pike Bridge near Pittsburgh, where rust and corrosion on the superstructure has prompted a request to replace the multiple-span through truss bridge.
But it is not that the people in Pennsylvania want to see the historic bridges disappear. While many feel that the bridge needs to be safe- especially in light of the bridge disaster in Minneapolis, Minnesota on 2 August, 2007- but many feel that maintaining the structures would not only make them safe but prolong their lives further. A survey conducted by the author for the Historic Bridge Conference in August reinforced this claim. Â Comparing the attitudes between the Europeans and the Americans, studies show that 2/3 of the participants in both sides of the Atlantic Ocean were of the opinion that a bridge must be safe but it also has to be maintained properly in order to make it safe. Â Various sources have claimed that maintaining and rehabilitating historic bridges are more cost-effective than replacing them outright. However, many of the historic bridges today are no longer able to carry large amounts of traffic in terms of numbers and size and this has created a paralysis between maintaining what is there and replacing those that are deemed unsafe period. This is especially noticeable in Pennsylvania during a bridgehunting tour in August, as many bridges are decaying because of the lack of maintenance. With that plus the problem with the infrastructure itself because of many roads that are an average of 30 years old and are in dire need of a makeover, and dealing with the future of the historic bridges, the state is at risk of becoming not only a third world country, but also a battleground between those wanting to see the historic bridges replaced at any cost because of their structural obsoleteness and those who want to see at least some of the bridges preserved as a piece of American culture and history. And with this battle, we will see many more historic bridges fall prey to neglect and eventually the wrecking ball. When this happens, many people will shake their heads and wonder why this happened when it did, while others will try and salvage pieces of American history to show to others, as one can see in the photo below.
To close, here is the answer to the riddle from last week: The sagging of one of the spans on the Venengo Veterans Memorial Bridge was clearly the result of a bent endpost and a roller which no longer functioned. A roller serves as an expension and contraction device on truss bridges and are ideal in extreme weather conditions. Because the roller no longer worked because of too much debris that could have been cleaned out, the only way the truss structure was able to contract and expand was through the superstructure itself.
Some helpful links:
Pennsylvania Department of Transportation Bridge Information Online:
Pennsylvania Historical Museum Commission Online:
Historic Bridges.org- Charloi-Monessen Bridge Online: Â http://www.historicbridges.org/pennsylvania/charleroi/
You can also find other bridges in this website with some info and commentaries by its author, Nathan Holth.
The author would like to thank Nathan Holth, Todd Wilson, and James Baughn for their help in the article, including the permission to use the photos.