Bridging the Gap

On September 26th, the New York State Department of Transportation issued a press release which announced "PROPOSAL FOR TAPPAN ZEE BRIDGE & I-287 CORRIDOR UNVEILED Team Recommends Bridge Replacement, Addition of Bus Rapid Transit & Commuter Rail."

The Tappan Zee Bridge is located about twenty five miles north of New York City, and is almost three miles long, including approach ramps. It was built in the early 1950s, is very heavily used, and the New York State Department of Transportation must do something about either extensively refurbishing it or replacing it. The press release indicates that remodeling it is not a viable option:

The Tappan Zee Bridge, constructed 52 years ago, was built according to prevailing standards in the early 1950s. While the bridge is safe, its design does not meet current national standards for structural elements and some of its deficiencies can not be addressed – even in the most robust rehabilitation scenarios – because of the structure’s basic design characteristics.

The replacement plan (or plans, since there are several options) and cost(s) are as follows:

Full implementation of the project team’s proposal would cost: $6.4 billion for a new bridge accepting bus rapid transit and commuter rail transit; $2.9 billion for bus rapid transit and highway improvements; and $6.7 billion for the build-out of commuter rail transit in the future.

The Tappan Zee Bridge proposal is notable for certain reasons:

1) It will cost a great deal of money, especially with the options for including rapid buses and a rail line. Because it spans one of the widest points of the Hudson River, it is a long bridge, requires many supports and therefore more preventive and actual maintenance.

2) The project reinforces the idea of transportation corridors. For cars or trucks to traverse the Hudson, they must all converge on the area of the bridge. There is no bridge within twenty miles north or south of this one. The mass transit additions of lanes for rapid buses and commuter trains further accentuates the bridge as being an important transportation artery; in other words, confining transportation to a corridor.

Considering the great cost of any new bridge, the focus on making this one even more of a transportation artery by adding mass transit capacity isn't surprising. On the one hand, we can look at this as confining travel to across the Hudson to just one structure for over 50 miles. But, to broaden the transportation corridor by building another bridge perhaps 10 miles to the south or to the north would not only require great expenditures of money on this other bridge, but would require new roads to take people to the bridge, adding even more expense.

Every place where transportation requires bridges endures bottlenecks and safety issues beyond those of just roads. Bridge costs for creation and maintenance are very high. As I've said in earlier posts, bridges are hammered day and night by heavy cars and even heavier trucks. And, adding special lanes for fast buses or trains will increase the load on the bridge, requiring more support, more maintenance and more expense. Certainly the mass transit additions to the bridge decrease dependence on cars, but they still add to the pounding the bridge must endure.

Our Aeroduct System will also need to cross rivers, but will require much less support and will endure far, far less pounding from the vehicles in the system. The pressure exerted by air cushion vehicles on their guideways (or "roads") is very light. An Aeroduct bridge would require some supports for longer spans, like that bridged at Tappan Zee, but these supports would be fewer and more lightweight. So, more crossings of the Hudson or other bodies of water could be built, all for much less money, putting an end to clogged transportation arteries. And, the guideways can be stacked horizontally or vertically, allowing far more throughput than current bridges.

It should be clear that any attempts to "upgrade" existing infrastructure for wheel based infrastructure will be hugely expensive and do little to decrease the congestion and high maintenance made necessary by the nature of that infrastructure. The Aeroduct System will cost money to implement, but it has far more potential than the roads and bridges of today, and will be vastly cheaper to build or maintain, will be safer, weather immune, faster and extensible. Faced with what will be a trillion dollar budget to just keep our existing roads and bridges from falling apart, and that is without adding any new capacity, shouldn't we be looking for an alternative?

Here is a color sketch of an Aeroduct "tube" crossing a river. As you can see, it uses open guideways leading up to the bridge, and then a closed tube across the water. A complete tube has inherent built in support, ideal for a span. If the river were wider than shown below, supports anchored on the river bed would also be needed.

From my perspective, we can continue to spend all sorts of money on keeping alive a transportation system that has many drawbacks, or we can spend our money building an entirely new system with many advantages. To find out more, here are links the Aeroduct System website and to other blog entries.

Hydrogen Solutions

In the September 23rd edition of the New York Times, Jad Mouawad's article called "Pumping Hydrogen" discusses the opening of a Shell station in Santa Monica, California, that is the first public filling station in the USA for hydrogen used in fuel-cell cars. This seminal event bodes well for the future, but as Mr. Mouawad points out:

And many energy companies remain skeptical of the long-term prospects for hydrogen, arguing, among other things, that even with government help the infrastructure costs would be enormous. ...

The largest obstacle remains the size and cost of the infrastructure needed to produce and distribute the hydrogen. The nagging issue is how to replicate a model that has served the petroleum age so well, and that was developed over a century.

There is no question that without an infrastructure for dispensing hydrogen for fuel-cell cars, not many of those cars will be made or used, their prices will remain uneconomical, and the potential of hydrogen will remain unfulfilled.

I've said it before, and I remake the point. Our Aeroduct System is the best way to implement hydrogen as the vehicle fuel of the future. The Aeroduct System, consisting of air cushion vehicles traversing lightweight elevated guideways, already represents a complete change in the ground transportation infrastructure. Implementing hydrogen fueling stations in this new infrastructure would be just another task needed to complete the new infrastructure. As the elevated guideways are built, the hydrogen fueling stations would become stops (or stations) along the guideways, along with stops for homes, offices, hospitals, schools, and so on.

And, not only will building a new infrastructure allow for complete integration of hydrogen stations into the Aeroduct System, the vehicles in the Aeroduct are the best at using the fuel. They need less power than automobiles, and are automated so they can refuel with or without anyone in the vehicle. Less hydrogen will be needed for powering the air cushion craft, and automated refueling will mean less human effort and less risk for fueling mishaps.

I believe hydrogen is the best fuel for the future. Of the main impediments facing employment of this non polluting fuel, the Aeroduct System solves the problem of how to build hydrogen fueling stations that are abundant as needed, and it simultaneously provides an economy of scale for fuel cell makers. The numerous craft in the Aeroduct will all use hydrogen fuel cells, and that will greatly decrease the costs of making fuel cells.

You can read about the many other advantages of the Aeroduct System at the Aeromobile Inc. website and other blog entries.

Building Better Bridges

Roads and Bridges magazine devotes itself to issues related to today's wheel based transportation infrastructure consisting, as the journal's name suggests, primarily of roads and bridges. In the August 2008 edition, editor Bill Wilson in his article "Ahead of Its Time" summarizes the successes in building the I-35W St. Anthony Falls Bridge in Minneapolis. This new bridge replaces the prior one that collapsed without warning in August of 2007. The article points out the faster than expected progress that was made, and the challenges faced in trying to quickly replace the faulty structure that had fallen last August.

From his article, it is clear that much intelligence and planning were involved in building the new bridge. This accomplishment reflects the many years of experience by those who designed and built the new structure. In the same publication, authors John Chiglo and Alan Phipps in their article "Brain waves over water waves" talk about the advanced technologies employed in the bridge that would help alert authorities to any potential problems before any serious failure.

In many ways, the new Minneapolis I-35W St. Anthony Falls Bridge represents the state of the art in infrastructure design and construction. Of course, all of this costs a great deal of money: $234,000,000 was the bid made by the primary contractor and the design team. Given the large number of bridges in the USA, some far longer that the one in Minneapolis, replacing all bridges with this kind of new construction will cost a very large amount of money. When the original Minneapolis bridge collapsed, many were worried that other bridges could suffer a similar fate, since many were reaching the end of their original projected lifespan, and just about all bridges, new or old, support more traffic than they were originally designed to hold.

Cars and trucks give bridges a tremendous pounding, which is why they must be built strong in the first place, and why they wear out over time. Their cement and steel components must be strong because the bridge is doing a yeoman's job in allowing thousands and thousands of heavy vehicles to cross over water. So, these bridges must be costly to build and costly to maintain, and of finite lifespan.

There is way to better use all that money needed to build bridges (and roads and elevated roads, too). A transportation system that does not require massive bridges would be much more efficient and economical. Our Aeroduct System, discussed in these blog entries, and on our website, will require passage over water in guideways that are far lighter, cheaper and longer lasting than any automobile/truck bridge could be. Bridges today are basically beat with a hammer every second of every day as heavy cars and even heavier trucks cross them. In contrast, the vehicles in our Aeroduct System glide through their guideways on a cushion of air, having a very light touch on the guideway surface. Aeroduct bridges can still be built using the intelligence and advanced sensing technologies available for cement and steel bridges, but with lighter and more flexible materials and much longer lifespans.

The color sketch below shows the simplicity of an Aeroduct bridge crossing a river. For wider rivers or other bodies of water, supports would be needed for the guideway, but those supports will have much less work to do than the supports for the bridges of today. The replacement of the much of our aging bridge infrastructure with the Aeroduct infrastructure would save a great amount of money in the building and maintenance of the structures, and the safety of using them. This is just one way of many Aeroduct System installations can make transportation far better than it is today.