The downside is that the number one expense of making bricks is energy.  so the cost of bricks will rise in lock step with energy.  The energy source, however, is flexible.  Electric heat or direct burning of coal or gas are most common, but gas from landfills is also being used.  Some brick factories are placed next to sawmills and burn sawdust and scrap wood as the energy source.  Many brick factories close during winter months due to high NG prices.

Seriously, one issue we have with concrete pavers is aesthetics.  They look nice when you first install them, but after a few weeks or months, weeds start growing between the cracks.  Property owners find this very unattractive.  The solution?  Spray herbicide regularly.  

But probably the main reason we don't use pavers more often is the expense.  Asphalt is a lot cheaper.

• The paving base. Clays and soils containing organic matter are bad. They allow the base to slowly compress over time. Virginia, if I remember correctly, has a lot of clayey soils. Drainable gravels and sand, when well compacted, are very strong bases. Roads built on solid rock last the longest.
  
• The size of the traffic that goes over the paving. Large vehicle like trucks damage the base and the paving materials far more than small vehicles.
  
• The weather. Freeze thaw cycles and de-icing materials such as salt can deteriorate a road surface very quickly.
  
• and finally high traffic volume of traffic also increases wear-and-tear.

My street, St. Andrew, is 28 feet wide (~8.3 m), one way, with cars parked on both sides.  The speed limit of 25 mph (40 kph)and common sense keeps traffic slower than that :-)

Narrow streets with rare off-street parking also keep urban density high.  More area for people & parks & green, less for autos.

Best Hopes,

Alan

I really wish the Ivy League schools provided high-quality classical education. Any "person of means" has a lot to learn from the history of city states in ancient Greece...

Meanwhile, really fat tires work well for me on the trikes with trailers.

We have some bad roads here in Minneapolis.  We also have chunks of ice and ice ruts in the winter time.  These make for some rough riding!

Much depends on how much the upper and middle classes try to maintain the easy-motoring lifestyle at the expense of everyone else, and how that class wrfare plays out.

If we work together, we might create a more sustainable transportation system.  If we move into even greater economic stratification -- whoch is the current trend -- we will not create a better, more sustainable transportation system.

If we continue to follow the path we are following, we will end up with bad roads and increased violence occuring on those roads.  That will be as big a consideration -- or bigger -- than potholes.

New York City, from its financial breakdown in 1976, well into the 1980s.

I assume (but don't know) that Detroit is pretty close to that, now.

The League of American Bicyclists recommends that the road is for all travelers. Cyclists belong on the road. Roads generally go everywhere people need to go. Bike paths don't and won't ever. My memory of Munich is a good one. Good public transportation, some off road bike lanes and striped on-road bike lanes almost everywhere else.

tstreet writes again - Ultimately, we need to dismantle the whole system and exclude cars from urban areas.

Excluding cars from urban areas isn't going to happen. But good planning and implementation for improving cycling in major cities is occurring at this moment. It's achievable and happening now.

Cyclists can and should work together to improve their cycling experience.

http://www.cybersalt.org/cleanlaugh/images/05/carbackfire.htm

And it sucks.

Bikes on sidewalks should be restricted to walking speed. Bikes on streets should be immune from some regulations that apply to cars. I am pro-bike rights, but think they should be on the street. Food delivery by bike should be restricted to streets.

I don't think young kids should have to ride in traffic, but neither do I think they have a right to terrorize and potentially injure elderly on sidewalks.