From otherworldly bridges to filled-in docks, here are some of the best and worst unrealised urban proposals for Bristol

Unpopular plans for a new ring road and thousands more houses on the south side of Bristol have recently led to a surge in local civic activity. Posters have been popping up across the city, and several hundred people recently descended on a church hall meeting with the mayor to make their feelings known.

This is not the first time Bristolians have clashed with would-be tarmac. In fact, if past campaigners hadn’t been so successful, much of the city centre and the beloved harbourside could have been turned into a plain of concrete and cars.

That said, some of history’s other urban proposals for the south-west capital would have been awe-inspiring. Here are some of the best and worst.

A spectacular bridge

In 1793 the aptly named architect William Bridges suggested a structure across the Avon Gorge in the spot where the Brunel-designed Clifton Suspension Bridge now stands. His design was so fantastic and otherworldly that the bridge that was ultimately built seems ploddingly mundane in comparison.

Bridges proposed a multi-storey arch, starting from the ground upwards, that would contain granaries, a corn exchange, a chapel and a nautical school.

Facebook Twitter Pinterest William Bridges’ original design. Illustration: The Brunel Institute

He was convinced the eye-wateringly expensive development would eventually amply repay investors, according to Eugene Byrne, the author of Unbuilt Bristol: The City That Might Have Been 1750-2050. The city was in the midst of a housing boom at the time, and Bridges believed that including a stone wharf on the Somerset side of his bridge would fuel similar construction across the river in the new suburb of Clifton.

The boom, though, was a bubble. The loss of investor confidence after it burst – possibly combined with a lack of engineering capability – meant Bridges’ beautiful behemoth was never built.

Walkways in the air

The postwar reverence for cars, baffling to many urbanists today, almost transformed Bristol unrecognisably. In 1966 the city’s planning team announced plans for roads flowing through the centre, but in an approach perhaps innovative for the time, they did try to recognise the importance of human-sized activity.

Their idea was to shift the pedestrians upstairs, on to a network of concrete paths and plazas that would be knitted together on stilts above the noisy roads below. The walkways would be lined with shops and cafes, the planners thought.

Facebook Twitter Pinterest There are a few traces of the pedestrian decking system that never was, such as the walkways and sidewalks over Nelson Street and Rupert Street.

They nearly got their way, but consultants hired by the council punctured their illusions. Concerns about increases in traffic and the profitability of the upstairs businesses meant only a couple of footpaths and plazas were built.

Filling in the docks

The same road-building enthusiasm that almost displaced commercial life to the air almost spilled into what is arguably the most attractive part of the city centre today. In 1969, Bristol city council announced plans to close the docks.

Having once been the lifeline for trade in and out of the city, by the 1960s most of Bristol’s cargo was instead going through the port down the river at Avonmouth. The city centre docks were shedding money, so the council planned to fill in a section the size of 83 football pitches. This was to be used for roads and offices galore.

Plans to reduce the water surface of the floating harbour had to be abandoned to get a bill allowing closure of the docks through parliament, but the council was still intent on building three bridges for motorways. Byrne says a combination of civic protest, party politics and shifts in the economy eventually meant the plans were abandoned.

The Harbourside Centre

The years that followed saw the docks bounce back from near death, with regeneration spurred by the return of Brunel’s SS Great Britain in 1970 and the relocation of the Arnolfini art gallery to the quayside in 1975.

In 1996 the Stuttgart-based architects Behnisch & Behnisch won a competition to design the Harbourside Centre, a planned state-of-the-art concert venue. Massive Attack, Portishead and the wider Bristol music scene were enjoying considerable fame, and the public-private coalition behind the plans was keen for the city capitalise.

Facebook Twitter Pinterest Model of the Behnisch & Behnisch design for the Harbourside Centre. Photograph: Behnisch & Behnisch

The building was due to be completed in 2002, with a 2,300-seat auditorium and a smaller one seating 450, alongside resident orchestras and dance companies. But the project was relying on the hope that the Arts Council would grant two-thirds of the £90m budget, and for various reasons that didn’t happen. The Harbourside Centre was dead in the water.

The Severn Barrage

Water was at the centre of another unbuilt plan for the city region. Ideas for a tidal power barrage across the Severn have been floated for more than 150 years. According to Byrne’s book, legend has it that Hitler planned to see the idea through if he successfully occupied Britain.

In 1840, the engineer Thomas Fulljames designed a dam-cum-railway-bridge about eight miles north of the city. The structure would have created a harbour to accommodate increasingly big ships and cut the journey time from England to south Wales, but the money just wasn’t around to build it.

Similar ideas have been discussed ever since, but each time the capital outlay required has been considered too high. In 2013, a parliamentary select committee reported that plans put forward by Hafren Power did not sufficiently address significant concerns about the effect of a barrage on wildlife. Environmentalists have proposed other renewable power ideas for the area, such as small scale turbine projects.

The Avon Weir

Another unrealised idea involved something similar to a barrage, but this time on a much smaller scale. In the early 1990s, the Bristol Development Corporation – a quango set up by the Conservative government with its own funding and freedom to regenerate a section of the city – proposed a weir on the River Avon where it runs between Spike Island and Southville.

Artist’s impression of the weir, from Bristol Development Corporation publicity material, 1991. Illustration: Bristol Development Corporation

It was thought the weir would provide attractive waterside views for homes and offices, thereby stimulating the regeneration of the former industrial area.

However, the plans would have affected flood-defence and drainage systems far beyond the corporation’s allotted area, which would have had to be addressed using money from other agencies. This, combined with a lack of funding for the weir itself, meant it was eventually forgotten.

The tramways terminus

Last year the mayor of Bristol, Marvin Rees, said the city would have its own £4bn underground system by 2027. The traffic-tackling plan could be seen as a descendant of the city’s former tram network, which stopped running in 1941 after a German bomb hit one of its power cables.

Facebook Twitter Pinterest Crisp and Oatley’s design for the tramways terminus building, 1895.

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In 1895 the Bristol Tramways and Carriage Company launched a competition to design a building at the point in the city centre where several tramlines met. It was won by Henry Crisp and George Oatley, but unfortunately their unique design never made it off the paper, due to opposition among some of the company’s shareholders and concerns about its practicalities as a waiting room for passengers.

Oatley went on to design several iconic buildings that make up the University of Bristol, including the gothic Wills Memorial Building.

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