In reply to the general thread on "why a new line" perhaps the page on the new
LGV Sud Atlantique will help. I use the current line to Poitiers quite regularly. I can tell you that the current LGV to Tours is a nightmare. When the train hits 220km/h you, quite literally, are being thrown all over the place, even seated. When the trains pass, the carriages are hammered with slipstream and quite literally shake. Imagine this at 300km/h. The line from Tours to Bordeaux is normal speed not LGV (Ligne Grand Vitesse) and it takes nearly 2 hours from Poitiers to Bordeaux. When the new line is in, it will be as fast from Bordeaux to Paris as the current slower trains from Poitiers.
Simply put they have to create a new line with a new path which runs more smoothly. The engineering works are currently under way and the AutoRoute from tours to Poitiers is diverted in several places as the LGV line interferes with the road. They are working on the whole length of the line at once. Also note the number of jobs, per year, for the project.
As for the "no" campaigns???? It's not just the UK
non a la LGVWhilst the UK has procrastinated about whether or not we even need a new high speed line, France, Germany, Belgium and the Netherlands have been creating a very high speed interconnected network of trains which allow fast paced travel between the countries and cuts air travel quite significantly. Even though air is often faster and cheaper than the train.
The UK has the most congested and most out of date rail network in the western EU. We need new solutions and high speed links. End of. Endlessly debating the whys and wherefores of the IF and the MAYBE is one of our modern UK diseases. We just need to get it done and move on to take the benefits. HS2 is only the beginning of a strategy which will spread throughout the UK. Until we get it started we will never work on the rest of the country. We need trunk rail links at high speed then regional rail links at normal speeds. Just like our road and motorway network.
We bemoan the loss of our country "as it was" then we fall into the trap of thinking like the "new country is". In time gone by we would not have been debating it for 3 decades. We would have done it. If the engineering was a challenge we would have developed the techniques to resolve the challenges and then sold that expertise to the rest of the world.
We ask what is wrong with our country today. I say "Just look at our response to HS2". To me it says it all....