Great post last Tuesday on our first half of the top 10 bridges in America. I just need to clear something up before I move on to the honorable mentions and top 5. While total length was a factor in the ranking, it was not a be all end all in what bridges made my list. You'll see a couple long bridges today, but also a couple of shorter ones. Several bridges can claim to be the "longest" using any number of different sets of criteria. These records are being shattered on a regular basis in Europe and Asia. However, I am not quite as familiar with the architecture and engineering over there as I am with it in this country. Perhaps in a future post I could do a little research.
In any event, here are the almost-5: the honorable mentions. Neat in their own little right, but not quite magnificent enough to make my top 10.
Tacoma Narrows Bridge: SR 16 and SR 14 over Puget Sound-Tacoma, WA
Seems pretty odd considering I referenced Galloping Gertie twice in yesterday's post. However, I find it hard to include a bridge that collapsed 4 months after it opened on a list of top 10 bridges of all time. Nevertheless, there were several engineering lessons learned as a result...and elementary physics students can marvel at the near perfect harmonic oscillation.
Leonard P. Zakim Bunker Hill Bridge: I-93 over Charles River-Boston, MA
I came very close to putting this on the featured list. I decided to omit it for a couple reasons. First, I did not want the list to be overrun with cable-stayed bridges that replaced antiquated cantilever designs. I have another one of those in the top 5 in addition to the Sunshine Skyway yesterday. Also, this bridge is a key cog in the Boston Big Dig, and an item on this bridge would inevitably transition into a lecture on the merits of the Big Dig, the politics thereof, and would then move into (leaky) tunnel technology. This is a piece on bridges after all. I must admit that it is spectacular to look at. Did I ever mention that climbing to the top of the Bunker Hill monument tires you out?
Woodrow Wilson Bridge: I-95 and I-495 over Potomac River-Alexandria, VA and Oxon Hill, MD
Drawbridges don't make a featured list. Period. However, DC's favorite bottleneck eeks its way into the honorable mentions because of the innovations added as part of its reconstruction in the 2000s. The express/local configuration is not new (I-270 has had it for years), but the bridge now has capacity for a dozen lanes...and a right-of-way for a high-speed rail corridor. It took a bridge that had more than tripled its originial design capacity and turned it into an engineering staple of the DC area. There's a problem though. It's still a drawbridge! While the reconstruction has lowered the number of scheduled openings from about 200 to about 70 per year, a drawbridge on the Interstate Highway System in my opinion is a no-no. Interstates are not supposed to have holes in it, especially I-95: the main street of the East Coast and probably the most important highway in the country, if not the world (still waiting for New Jersey to close that little gap...) I must admit it is much prettier to drive over though now than it used to be.
Fort Pitt Bridge: I-279, US 30, and US 22 over Monongahela River-Pittsburgh, PA
This bridge makes the honorable mention list for purely selfish reasons alone. This:
Benjamin Franklin Bridge: I-676 and US 30 over Delaware River-Philadelphia, PA and Camden, NJ
The "other" Big Ben (and I'm not referring to the dude with the busted schnoz in Pittsburgh) is the best way to get into Center City Philadelphia from New Jersey. The alternatives are the Whitman, which takes you too far south, the Commodore Barry which dumps you in Chester, and Scudder Falls up by Trenton...but at least that last one's toll free.
Interesting, diverse sample in the HMs, but now we get to the big guns. I now present to you the top 5 bridges in America!
5) Brooklyn Bridge: East River-Manhattan and Brooklyn, NY
Total length-1.1 miles
Span-Suspension
Max Clearance-135 feet
Toll-None
For several years around the turn of the 20th Century, this was the only way to get from Manhattan to Brooklyn, either by foot or by streetcar. Then the other East River (toll) bridges and tunnels came into being. The advent of automobiles and interstates relegated the Brooklyn Bridge to second-class status as its landing points are not in the most convenient of locations in New York City. Nowadays, commuter traffic would take the Queens Midtown Tunnel, or the Triborough Bridge to get from Long Island to Manhattan as these structures are part of the Interstate System. Nevertheless, the importance of the Brooklyn Bridge to the NYC skyline is unparalleled. Completed in 1883, the bridge was (obviously) the first to accomplish several things in the world of bridge building. Among others, it was the first to use steel cable suspension design. For about 20 years, it was the longest suspension bridge in the world, regardless of specification. I also can't think of another bridge that has concrete towers (Jeff...you're response?). The Brooklyn Bridge is also a popular escape route for people to get out of Manhattan quickly. People flooded the bridge following the September 11th Attacks and any one of a series of blackouts that have a tendency to plague New York City.
4) Arthur Ravenel Bridge: US 17 over Cooper River-Charleston, SC
Total length-2.5 miles
Span-Cable Stayed
Max Clearance-186 feet
Toll-None
Oh boy, this baby is impressive. This is another example of a cable-stayed bridge that replaced an aging, antiquated cantilever design. The original Grace Bridge was originally one of the largest cantilever designs in the world, so it was unique in its own right, but as with most cantilevers, in its later years suffered from over capacity and metal corrosion. A twin bridge constructed in 1966 alleviated some of the traffic problems, but was clearly not a long term solution. Work on the Ravenel Bridge completed in 2005 with the grand opening and demolition of its cantilever forerunners. The double diamond tower design was actually selected by local Charleston residents, as they felt it blended in the best with the architecture of the city. The 186 foot clearance is 30 feet higher than what the Grace Bridge had to offer. I already explained the advantages of cable-stayed design over other designs in my post on Tuesday. See the item on the Sunshine Skyway. I also have another video clip from Freewayjim. This is a short auto tour of Interstates in the Charleston area with a focus on the Ravenel Bridge, going over it both northbound and southbound. As you might tell, he's a fan too. Love the choice of music too.
3) Delaware Memorial Bridge Twin Span: I-295 and US 40 over Delaware River-New Castle, DE and Pennsville, NJ
Total length-2 miles
Span-Suspension
Max Clearance-174 feet
Toll-$3 (Westbound only)
This bridge is one of the most important bridges in the United States as a traffic link. Since I-95 is (ahem) incomplete in the State of New Jersey, the most direct route between Baltimore, Washington, and the Southeast to New York City and beyond is to take this bridge to the New Jersey Tax-pike (what?), thus bypassing Philadelphia entirely and seamlessly reuniting with I-95 at exit 6. Even when (if?) 95 is completed by way of the Bristol Interchange Project, long distance traffic wishing to bypass Philly will want to use this bridge instead of going all the way into Pennsylvania and back into New Jersey. Most everyone I know has been over this bridge several times. As another important milestone on the way to Grandma's house, I too am very fond of this bridge and its conspicuously ugly green towers that can be seen from miles away. It is also one of the first suspension bridges to be twinned (in 1968). This became all the more important when it became evident that New Jersey was in no hurry to close the I-95 gap. Thus, the Delaware Memorial Bridge became by far the best option for travelers moving between New York and points south. As a war memorial, the originial (north/eastbound span) was dedicated to Delaware and New Jersey veterans from World Wars I and II, and the newer (south/westbound span) was dedicated to veterans from the Korean conflict and Vietnam (and more recently to Operation Desert Storm).
2) Golden Gate Bridge: US Route 101 and SR 1 over San Francisco Bay-San Francisco, CA
Total length-1.7 miles
Span-Suspension
Max Clearance-220 feet
Toll-$6/$5 with Electronic Toll Collection
I guess no examination of bridges would be complete without including Big Red. This bridge is more than just its iconic "International Orange" towers (the paint is actualy important as it protects the steel towers from corrosion in the salty air, so it's not totally aesthetic). It is a vital connection in the Pacific Coast Highway, linking San Francisco with Marin County as part of US 101. Scenery is simply magnificent, as this bridge truly crosses a golden gate from the Pacific Ocean into San Francisco Bay. The bridge might still be high up on the list (despite the color scheme) because of its characteristic fog, and featured prominence on the title card of a certain 90s pre-teen sitcom. On a darker side, the Golden Gate Bridge is also one of the more popular places to...uh...attempt self-inflicted passing from this life to the next. Thus, special dedicated hotline phones (located at the ends of the bridge and in the middle) are placed on the bridge so that potential jumpers have a direct and immediate line to a crisis intervention center in the San Francisco area. Like the Mackinac Bridge we looked at yesterday, the Golden Gate has the capability to sway (bridge deflection) to compensate for high winds. It can sway as much as 16 feet. Check out this neat video from the Golden Gate website to see how the swaying works. Of course, this is California, so earthquakes are never out of the question. While the Loma Prieta Quake of 1989 decimated the Bay Bridge, the Golden Gate was spared as the epicenter was 60 miles away. Nevertheless, the original design was subject to the same flaws as the Bay Bridge. Thus, a seismic retrofit project was initiated and is ongoing today. Learn more about that here.
1) Verrazano Narrows Bridge: I-278 over Lower New York Harbor-Staten Island/Brooklyn, NY
Total length-2.6 miles
Span-Suspension
Max Clearance-228 feet
Toll-$13/$9.60 with EZ Pass; Staten Island residents earn varying degrees of discounts (Westbound only)
What can be said about the mighty Verrazano? Wow. The only real drawback to this bridge is the outrageous toll. Fortunately, it's only one way, and the people who would stand to be pinched by it the most (Staten Island residents) get a deep frequent traveler discount. Check out the MTA website for more information. This bridge really is a combiation of all of the best that New York bridges have to offer: double deck, long suspension span (longest in the world for quite some time), 693-foot tall towers. I for one have only traveled over it once (Westbound-on the upper deck). This was several years ago, but I still remember it. It was magnificent. You can see for miles in both directions of New York Harbor. Once you land on Staten Island, it's kind of a major letdown. The long suspension span was revolutionary for its time, but it was necessary. There are only 3 ways to get on and off Staten Island (and two of them dump you in New Jersey...). The Verrazano is the only way for Staten Island residents (other than the Ferry) to access the other boroughs of New York. Therefore, capacity needed to be necessarily large. The closest points between the islands were still about 3 miles, and tall ships needed to traverse the harbor, so an extra long suspension span was also necessary. Thanks to urban planning and engineering icons such as Robert Moses and Othmar Ammann, the result is one of the most spectacular pieces of engineering, metalwork, and architecture, not just in the country, but in the world. I always knew they could do something right in New York :-). Bravo.
I hope you enjoyed our little trip around the country by bridge. This is I feel one of my best series of posts so far. Please please please leave comments. I hope these great structures generate some good discussion.
As always, thanks for checking into Caputo's Corner and hope to see you soon.
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