Connecting Glasgow - Phase 2: Reshaping our strategic road and rail networks

For Scotland's economy to reach its potential, Glasgow needs to be firing on all cylinders. Fixing the city's long-term strategic transport challenges shouldn't be seen a local concern – it is an urgent national priority.

That is the context in which we have published today a blueprint to transform Glasgow's connectivity. The recommendations by the Glasgow Connectivity Commission aim to fundamentally shift the economic performance of the Scotland's only metropolitan area, allowing it to compete in an evolving global economy for jobs, investment and immigration and so drive inclusive and sustainable growth in Scotland.

The numbers behind this are stark. Glasgow is home to a third of Scotland's jobs and a third of its economic output but experiences a 13% productivity gap with the rest of the UK. Bringing the average output per hour worked up to the UK average would generate £4.6bn a year for the Scottish economy, a level of growth unlikely to be equalled by investment anywhere else in the country.

This is about transforming two economies – and bridging the gap between them. The evidence presented to us over the last year painted a stark picture of two very different cities, with transport playing a critical role in dividing up access to jobs, connections and opportunity.

Across Glasgow, we found a similar story of people living close to Glasgow's suburban rail network – the second biggest in the UK – enjoy good access to Scotland's biggest area of economic activity while those who don't live near a train station suffer far higher rates of socio-economic deprivation. And we heard compelling evidence that the size of the population with reliable access to the city has a critical role in driving its productivity.

Our proposals to develop a Glasgow Metro system aims to heal this divide, dramatically expanding the number of people who have quick and reliable access to the city centre and ensuring the benefits of high-value, well-paid jobs can be spread further.

This is a 20-year project that can be delivered in phases, line by line, taking advantage of Glasgow's disused rail routes abandoned largely after the Beeching cuts and wide, boulevard streets such as the western section of Great Western Road and Edinburgh Road designed to accommodate trams. Many cities would give their right arm for this opportunity.

The starting point for this network is Glasgow Airport and the string of locations south west of the city which are in desperate need of a modern public transport network: the Queen Elizabeth University Hospital, Braehead shopping centre, the Advanced Manufacturing Innovation District Scotland and Renfrew, the largest town in Scotland without a rail station.

We need to ensure we don't choke off the very strong growth we are seeing on the rail network, where numbers have soared. At Glasgow Central alone, journeys have jumped from 20m to 30m in just a decade. Our largely Victorian network is now bursting at the seams and our options for incremental improvements are largely exhausted.

The only long-term solution to this growth is to properly link Glasgow Central and Queen Street stations, allowing trains to run through the city and so dramatically increasing capacity. The tunnel we propose building would make Glasgow unequivocally the best-connected place in Scotland and allow areas such as Inverclyde and Ayrshire to have regular, fast services to Glasgow and Edinburgh.

At Glasgow Central, we need to prepare for the arrival of HS2 services when the new line is built between London and Birmingham. This is not just about ensuring Scotland is not left behind as journeys to London get faster for cities such as Manchester, Leeds and Birmingham. It is about unleashing investment that can transform the area that the station serves.

Think of the changes made to St Pancras and King's Cross and how investment in those stations helped regenerate the wider areas, turning seedy, dangerous neighbourhoods to some of the most prosperous in the world. We believe the "Blackfriars on the Clyde" solution – building a new concourse east of the existing station and across the river – would unlock the same type of transformation to an area of the city centre that is woefully under-utilised.

This package of measures is bold, ambitious and transformative. It will help shape a city that is greener, more attractive and sustainable, ensuring growth is not choked off by rising vehicle pollution and road congestion and opportunity is not sharply divided between connected and isolated areas of the city. We're confident this will secure and sustain Glasgow's role as the engine-room of Scotland's economy.

Professor David Begg is a former Government advisor on transport and chairs the Glasgow Connectivity Commission.