Half a century ago, Tokyo engineered one of the great urban transformations of history, going from a beat-up Asian megalopolis to a first-world city. The trigger was the 1964 Olympics.

The choice of Tokyo was controversial. It had miles of bad roads and few decent hotels. Just 20 per cent of its residents had flush toilets in their homes. Pollution was so bad that oxygen cylinders were sold in vending machines.

By the time the Olympic flame was lit, however, Tokyo had a new monorail and bullet train lines, expressways, luxury hotels and a refurbished international airport.

The result is hardly pretty: an endless landscape of drab, boxy buildings with too little green, crisscrossed with ugly flyovers and studded with characterless mixed development complexes.

So expectations are high ahead of the Tokyo Olympics in 2020. Governor Yoichi Masuzoe has pledged to make it the planet's No 1 city, using the games as a launch pad.

Olympic venues

In addition to 22 new Olympic venues, plans include new roads and railway lines, a huge waterfront redevelopment and rebuilding chunks of the city centre.

But this ambitious makeover has triggered withering criticism. “We are no longer in 1964,” says Kengo Kuma, one of Japan’s most revered architects. He calls plans to replicate the architectural vandalism of Japan’s first Olympics a “nightmare”.

The fight between two competing visions of Tokyo's future is symbolised by plans to rebuild the 1964 Olympic Stadium. At nearly 290,000sq m (3.1 million sq ft), the new facility would have been by far the biggest in the history of the games. And it would have overwhelmed one of the few large expanses of green in the city centre, said Fumihiko Maki, another top architect.

The criticism forced Zaha Hadid, the stadium's London- based designer to announce a scaled-down version this summer. But the old one sits gutted and empty, awaiting a final decision before demolition.

A group of 100 designers says rethinking the centrepiece of the games does not go far enough. Team Timberize, a non-profit organisation, wants all the new Olympic facilities built with wood.

Mature city

Japan

can no longer afford to act like it’s still the 20th century, says Atsushi Yagi, a director of Team Timberize. It must think like the mature city it is, he says.

Disquiet over construction plans have been heightened by growing concerns about cost. Estimates for the stadium refurbishment have more than doubled as construction and labour costs soar under Abenomics – Japan’s bid to end years of deflation, named after prime minister Shinzo Abe.

City officials revealed recently that this year’s consumption tax hike of 3 per cent had not been factored into the original budget.

Japan’s media says the government is scrutinising Olympic successes, such as London and Sydney, and failures, (Athens) for lessons.

The government’s initial price tag for the games was 409 billion yen (€2.95 billion), which it planned to offset with a three-trillion-yen Olympic windfall.

That is almost certainly optimistic: every single Games since 1960 has failed to meet the cost target. The average overrun has been 179 per cent.

The 1964 event cost many times more than its predecessor in Rome, and triggered the start of Japan’s addiction to bond issuance, which continues unabated today.

The question of cost is likely to loom large over the next six years. Last year, Japan passed one quadrillion yen in public debt for the first time – equal to the economies of Britain, Germany and France combined.

If, as some expect, Abe’s economic experiment runs out of steam, the city faces a painful post-Games hangover.