If an urban district is neglected and under-invested, it is often because it is poorly connected to the rest of the city.
Accordingly, when a decision is taken to regenerate that area, one of the first moves is to improve its connectivity.
This was dramatically demonstrated in 1999 when Birmingham’s Eastside was declared a regeneration area, intended to reproduce the success of the International Convention Centre and Brindleyplace in extending the city centre to the west.
The first move of the council’s Eastside planning team was to seek funds to demolish the elevated Inner Ring Road and Masshouse Circus. They correctly foresaw that no regeneration would take place in Eastside if it continued to be separated from the city centre by the notorious “Concrete Collar”.
In place of the viaduct we now have the new boulevard of Moor Street, and the buildings of Masshouse, Hotel LaTour and Birmingham City University, which I am pretty sure would not be there had the Concrete Collar remained.
However, as I have written previously in this column, the severance caused by the ring road is to be reproduced, but even more extremely, by the proposed new High Speed 2 terminal.
In the Curzon Masterplan, published last year by the city council, which contains ambitious targets for the regeneration of Digbeth, there is to be no fully-public street connecting the city centre on one side of the terminal and Digbeth on the other, along a stretch between Moor Street Station and the Middle Ring Road. This is a distance of one kilometre.
Apart from bicycles, the only vehicles which can cross under the terminal will be taxis and Midland Metro trams, on the planned extension of the city centre Metro route into Digbeth.
This is extraordinary, and puts a huge responsibility on the Metro for the successful economic regeneration of Digbeth.
In the Curzon Masterplan, the Metro route goes under the terminal along New Canal Street, and then turns left down Fazeley Street, past Fazeley Studios and The Bond.
However, since this was published, Digbeth Residents Association, an active and influential local body (I am an associate member) have argued that instead of going through the middle of Digbeth along Fazeley Street, the Metro should go along High Street Deritend, the dual carriageway that used to be the A41.
Consequently, Centro has now made High Street its Route Option 2, and in October it carried out a public consultation exercise to find which of the two routes potential users preferred.
They had about 400 responses, which it considers a good result, although I expected there would be more. News on how people voted will be published around January.
It will be just one factor in the decision where to run the Metro: obviously comparative costs will be a major factor.
Which is the better of the two routes? There are merits in both. Route Option 1, down Fazeley Street, would take the Metro through an area which currently has no public transport, and arguably it could effectively open up for new development a large area of Digbeth.
In particular, it would connect directly with two large canalside redevelopment sites which sit on opposite sides of Fazeley Street: Warwick Bar and Typhoo Wharf.
Both of these sites, owned by Isis Waterside Regeneration and the Gooch Estate respectively, have enormous potential for making new places.
But when the barrier of the HS2 terminal is built, they will be difficult to reach by car. Could the convenient accessibility of the Metro be enough to make them viable? I would like to think so, but I’m not convinced.
The big argument against Route Option 2, along New Canal Street, Meriden Street, and then High Street Deritend, is that High Street is already well served by numerous bus services.
Also, being longer, Route Option 2 is likely to be more expensive. But on the other hand, this route connects with a number of places where lots of people want to go. South and City College, Birmingham Coach Station, the Custard Factory and the Rainbow music venues are among them.
There is one compelling reason why I would like to see Route Option 2 chosen: it could be the catalyst for the complete redesign of High Street and its transformation into an attractive boulevard. If Route Option 1 is chosen, this reconstruction may never happen.
High Street is a medieval street, originally connecting the centre of Birmingham at the Bull Ring with the village of Deritend, across the River Rea. Its winding profile expresses its origin as a country lane. But the narrow street was destroyed between the 1930s and the 1950s by the demolition of its southern side, and its widening into a dual carriageway.
Attractive and historic buildings survive on the north side, although inappropriate car showrooms were misguidedly permitted to be built there in the 1990s. The development on the south side is coarse and sometimes hostile. It is an ugly street, with more road capacity than it needs.
Here is a thought. The dual carriageway has a similar width to Las Ramblas in Barcelona, one of the world’s great streets; about 30 metres between buildings. Las Ramblas is also winding, because it was originally a river-bed. Could High Street Deritend be made similar (though with added Metro tracks) to Las Ramblas? I think it could.
A great street has simple ingredients. You need spatial enclosure and active building frontages (those car showrooms and blank industrial frontages will have to go), big trees, good quality surface materials, imaginative lighting, and lots of space for pedestrians.
We also have a river, the Rea, now invisible, where Deritend Bridge, demolished in 1937, used to punctuate the street.
It could be rebuilt, so that as the tram crossed the bridge on its way to the Custard Factory one could look out and see the river on either side. Centro and city council, please start drawing.
Joe Holyoak is an architect and urban designer based in Birmingham