Congratulations for your thorough analysis of the environmental impacts of High Speed 2 (Will HS2 help the climate – or will it make things worse?, 3 February; Barn owls, bats, butterflies, birds – all now at risk, 3 February). The escalating costs of HS2 call into question the way the UK designs and evaluates big infrastructure projects. We should take much more account of the impact on development and land values, especially if the uplift were shared with investors. Spending £3bn on land acquisition to date is surely wasteful. But little can be done without reintroducing regional and strategic planning.

Before we turn our backs on Europe, we should learn from how the French succeeded in growing their towns and economies while keeping down car use and pollution. The crucial difference is not going for one grand national project or another, but joining up investment in development and infrastructure at a city region level, as a comparison of Lyons or Lille with Leeds would show.

So let’s start by revisiting attempts to come up with regional or sub-regional plans and ask how much of the costs could be recovered from the uplift in land values. The late Sir Peter Hall proposed a relatively economic way of improving rail services, later named HS3. This would use a series of improvements, such as better signalling and junctions, not one big project, which is almost bound to go wrong. Such a policy would produce faster results, using public investment to secure multiple benefits, not just faster long-distance journeys.

Dr Nicholas Falk

Executive director, The Urbed Trust

• At last the necessity for HS2 is being steered away from the need to get from London to Birmingham a bit quicker (The case for, 4 February; The case against, 4 February). The essential issue is capacity. If the public wants fewer heavy trucks on the roads then additional rail is the only answer. There are virtually no spare paths between London and the Midlands on the west coast mainline: £8bn-£10bn was spent in 2008-10 upgrading that line, but there is now nothing spare. A new line is needed, so why would you build a slow one? The data is regularly published in Modern Railways, but it is apparent that politicians and their advisers don’t read the industry journals.

In all the furore about rising costs, politicians never ask why it is four times more expensive per mile compared with the LGV Est line in France. Perhaps land prices are lower in France, and each new LGV line has been dovetailed into existing termini in Paris, which might explain some of the lower costs. But really, four times as much here? Who’s making a killing?

Finally, why are the arguments presented as either we spend on HS2 or upgrade areas in other parts of the country? Why can’t it be both?

Robert Ashley

London

• Hurrah! At last you have hit the nail on the head and made the clear and coherent case for HS2 (Editorial, 6 February). Taken together with enhancement and integration of local networks to ensure maximum access to HS2, there is little doubt that the new line will more than pay for itself and stimulate development across the Midlands and north. There’s already been digging aplenty in Birmingham. More please, Mr Johnson, and soon.

Roy Boffy

Sutton Coldfield, West Midlands

• Here are some other ways to spend £106bn: 15 tram systems like Manchester Metrolink £42bn, free bus services for everyone for 10 years £30bn, free ebike for every adult £34bn. Well-funded local transport for everyone is what we require.

Edward Fielding

Shipley, West Yorkshire

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