London's transport bosses are telling travellers on the tube system to beat the heat by carrying a bottle of water with them when they venture underground.

But how many of us are refilling our bottles with tap water rather than pouring money down the tube -- not to mention the cost of recycling the plastic bottles -- by buying a new bottle of water each day?

Cue the National Hydration Council whose eye-catching advertising campaign to encourage people to buy more "naturally sourced bottled water" -- on health grounds -- featured prominently on the underground network earlier this year.

The worrying thing for the bottled water lobby is not that people are doing what would appear to be the most sensible thing and refilling their bottles from the tap, but that Britons are replacing bottled water with sugary drinks instead.

We're told that sales of bottled water fell by 7 percent last year, with 71 percent of that decline the result of people buying sweet drinks instead. Good news for the soft drinks industry perhaps, but a worry for health officials.

Meanwhile, beneath the streets of London, the hot and flustered faces of fellow tube passengers shows just how dire it is on board the capital's underground trains when the mercury rises.

With a decent air-conditioning system on most lines a distant prospect, Transport for London (TfL) could show it cares by offering each of its cash-strapped passengers a free TfL water bottle and the opportunity to refill them at its stations.

When in Rome . . .

As I watched the snow fall gently from London skies on Sunday night, I asked an acquaintance if I would have to go to work the next day.

My Canadian “snow radar” — fine-tuned from living in the snowy cities of Toronto, Ottawa and Halifax — was telling me that there wasn’t going to be much accumulation, but given the regular daily London transit delays in fair weather during the rush hour, I had a gleeful feeling a “snow day” might be in store.

“If the snow is 3-feet deep you might get away with it,” said my acquaintance, who commutes in and out of London from the Southwest each day.

I awoke the next day to discover that he was wrong.

Almost the entire Tube system was shut, buses cancelled and within a few hours Heathrow, the world’s busiest international airport, had closed, although there was nowhere near 3 feet of snow.

The heaviest snow fell in southern England. Epsom, Surrey, had depths of 31 centimetres (12 inches), south London had 28 cm and the North Downs in Kent got 25 cm.

Where I live in southwest London, it looked like the snow was about 15 cm deep.

(Can you tell I am trying not to smirk as I write?)

That amount of snow would be noticed in a Canadian city - but barely. It would take much more than that to put the brakes on the engines of capitalism.

Some years ago in Toronto, so much snow accumulated so quickly that former Mayor Mel Lastman called in the army to help dig out in a frantic effort to keep the city operating. This action left Toronto open to the ridicule of the rest of the country, which in general sees much more annual snowfall.

I lived in Washington, D.C., for four years and witnessed that city shut down due to a few inches of snow several times. President Obama, who moved there from Chicago in January, mocked the city last week for its panic over a day and night of snow and freezing rain, which led to school closures.

The storm in London this week cost the UK economy up to 3.5 billion pounds ($5 billion) according to Britain’s Federation of Small Businesses.

Even my British relations expressed disgust at the transit closures.

An aunt near Maidstone, Kent, said: “It’s typically British.”

A cousin in Paignton, Devon, said: “I’m sorry, I just don’t believe it.”

Their attitude seemed to be that people were just looking for an excuse to take the day off.

And why not? Given that it was the worst snow here in almost 20 years, I think it does call for a holiday. I certainly enjoyed my two days working from my studio flat.

“What are you doing at home? You are used to worse than this,” a Canadian colleague asked. I’ve never had a day off work due to snow in Canada.

“When in Rome, do as the Romans do,” I replied.

Looking forward to the possibility of more snow . . .