Cold, Surface Courses
The recent chaos in the South East (no the whole country was not grinding to a halt) because of a bit of cold weather makes me wonder whether full consideration is given to the different thermal properties of porous Thin Surfacings.
I have no idea what the particular cause of this severe disruption was, and I can only make my judgment from television coverage, but there did not seem that much snow. I did however hear constant reference to ice on the road surfaces.
I wonder how many out there who have responsibility for road networks realise that porous road surfaces chill a lot quicker than impervious surfaces and are a lot slower to warm up when temperatures rise.
Salt that is spread is also known to fall in to the voids in the surface and not be available to be spread further by the wheels of traffic. 
This process is well documented and if you use a good search engine, like Google, or Directhit and enter a combination of suitable keywords, such as porous asphalt, thin surfacing, winter maintenance, salting, road gritting, etc., etc., you will obtain lists of items pertinent to this problem which you can browse. 
Perhaps I can direct you the the Research Compendium, provided by the Highways Agency. In particular an item that refers to the winter maintenance of Thin Surfacings, although I am not aware of this work being published as a TRL report.
I am aware that some parts of the Highways Agency have issued instructions that the spread rate of salt should be doubled on lengths of Thin Surfacing because of its different thermal characteristics when compared to existing surfacing materials. 
All this extra salt will find its way in to streams and rivers, not very environmentally friendly.
In my opinion, if we are going to pursue the use of proprietary Thin Surfacings as the principal bituminous material for road surfacing there has got to be some serious thinking in how it is to be used and maintained, and the subsequent funding implications.
By this I mean thinking that is genuinely related to road pavement construction and maintenance, and how it will subsequently affect road traffic, road construction/maintenance budgets and the environment.
Most of the thinking I have perceived, up until now, regarding Thin Surfacing seems to be mainly related to commercial interests and politics.
I personally believe the decreasing noise levels associated with Thin Surfacings is a bit of a smoke screen, and attention to traffic speed and the size, and air pressure, of "super single" tyres could return a far more cost effective solution to road traffic noise. 
But please, please, do your own research, read the copious amounts of technical information that there is out there related to this subject, form your own opinions, attain your own knowledge and understanding of the factors involved, then make judgments.
Personally I find information derived from European, particularly Scandinavian, road research facilities most interesting.
And, perhaps you would like to carry out you own very rudimentary survey as to which road surfaces may be of the more "modern" porous (colder) type, and which may be the more traditional impervious (warmer) type.
As you drive down the motorways, trunk roads and principal roads in some authorities take note of which surfaces are still wet, and dark in colour, and which are dry with the salt evident as a white dusting.
It is most likely that the dry surfaces are the more traditional, impervious, warmer surfaces.
But, before I get a flurry of emails saying I am not presenting a balanced view on the subject, porous materials do have properties that are lacking in impervious materials. 
Porous surface courses will reduce spray from vehicle wheels, and generally they are quieter.
So, what am I saying.
I am saying, know your road making materials, consider what is needed at a particular site, do your research, do some small scale trials, consider the practicalities as well as the nice theories, take some calculated engineering decisions, be ready to support the decisions you have made, and even after all this caution if their should be failure, investigate it thoroughly.
Do not just specify/purchase a product because somebody tells you it is wonderful !  

Interesting Websites
There are many, many interesting websites "out there", that are related to highways maintenance and road construction. 
So many that I cannot just make a big list for all of you to plough through, but what I can do is include include what I think are the more rewarding sites I have found to date on my two links pages.
But from time to time I come across other sites which are certainly worth a look which I do not feel are a natural fit for a permanent presence on this site.
So. I am including a couple of sites below that I must thank the "New Civil Engineer" for bringing to my attention, in a recent published journal which is supplementary to their main weekly magazine.
These sites were obtained from an "Editors Choice" list of websites, some might think there is a possible omission, but perhaps this site is not sufficiently "mainstream" for inclusion.
Out of the list provided by the Editor of NCE, and I have looked at most of them, the two I particularly appreciated are :-
Guide to free engineering software
and,
Where to buy and dump used materials, (meaning materials related to re-use in highways maintenance and construction)
Have a look and see what you think.

Motto of the Month

"In the land of the blind the one eyed man is king."