Old age is the destination no one wants to arrive at. Yet more and more of us are headed in that direction. Over the next 20 years the number of people over 85 in England will double and the number over 100 will quadruple. This week the Government launched a consultation into the funding of social care for the elderly, ten years after a royal commission reported on the same subject.

Old age, in short, has never been more newsworthy. Or less visible. Cast about for a cultural reflection of our ageing population and you'll have trouble. Old people are allowed out in a small number of severely restricted capacities. War veterans are fine, in Channel 4 documentaries about the Second World War or wheeled out for Lest We Forget interviews around Remembrance Day. The Rolling Stones are there to give us hope that our mojo will still be in working order at pensionable age. Then there is the remarkable Diana Athill, at 92 a lucid and amused spectator of extreme old age, reporting from the nonagenarians' front line in her remarkable memoir, Somewhere Towards The End. And perhaps Carmen dell'Orefice, the 76-year-old supermodel who, asked recently whether sex was still important (Ooh! the nerve!) replied with spirit: “Is breathing important?”

For fictional representations of the elderly you have to search harder still. There is Dot Cotton on EastEnders, her character given real depth by the 'Stenders scriptwriters, who clearly realise what a pearl they have in the actress June Brown. Then there's Catherine Tate's terrible, foulmouthed Nan. The patriarch Joe Grundy on The Archers with his fearful trademark cough (“Bleuch, bleuch, hawk, spit. It's me Farmer's Lung, missus”) and 89-year-old Jack Woolley, once a pillar of the Borsetshire business community, now much reduced by Alzheimer's. And...And... well, I suppose the BBC's sitcom Benidorm, in which EastEnders' Pauline Fowler was surreally resurrected in a guest-starring role, vengefully driving a mobility scooter. But I don't think that really counts.

There was a time on telly when oldies were, if not quite resurgens, at least given some good lines. Galton and Simpson's Steptoe and Son, first cousin to the agonising tragi-comedies of Pinter and Beckett, gave Wilfred Brambell as the revolting ancient, Albert Steptoe, a terrible power over his melancholy, sensitive son, Harold. More recently The Vicar of Dibley fielded a cast of characters of whom two thirds were in a state of comically repulsive decrepitude. It's not much, but there was at least an acknowledgement that the old were Us, rather than Them.

When did this change? And why, given that it's not the young who actually have the power to form popular taste? That is the role of the established middle-aged, for whom old age is the next stop down the line. Perhaps a clue is to be found in the delicious power and energy of new Labour, sweeping away fusty tradition, cobwebbed Tory attitudes of hierarchy, privilege and pointless ancient tradition, not to mention the sclerotic resentments of old Labour. Bliss was it, in the new Labour dawn, to be alive, and to be young was very heaven. Which rather implies that to be old was very hell. Not that they meant it like that, I am sure. But a culture ensued in which life expectancy steadily improved, but its inevitable consequence - oldness - was regarded as a shame or curse, to be hidden and ignored as in earlier times disability or illegitimacy might have been.

Which brings me to Sue Bourne's extraordinary film for BBC One, Mum and Me, to be screened next Tuesday in the not exactly prime slot of 10.35pm. Bourne is a film-maker with a keen eye for domestic strangeness. Her last project, My Street, examined the hidden dramas behind the front doors of the street in London where she lives. Mum and Me brings the same technique of fine observation to the even more personal narrative of Bourne's 84-year-old mother, Ethel, who is suffering from Alzheimer's.

There is a conventional narrative structure for this sort of film: the expectation is of a dying fall. The film-maker charts her subject's gentle decline, engaging en route the viewers' pity and terror until the solemn final moments when the camera cuts tactfully away (or remains tactlessly running). A stark notice just before the credits roll adds the final full stop to the narrative of a life.

This is not how Bourne's film works. There is little structure, no progression, no solemn announcement of the story's end. Bourne did her own filming with the help of her daughter, Holly, though neither of them is qualified to operate a film camera, with the result that the machine spends a good deal of time falling off the surfaces on which it is insecurely propped with Ethel's incontinence pads, filming upside-down and shooting in lurid negative. The course of the narrative is almost equally haphazard. Bourne had prepared herself for her mother's decline. But what actually happened during three years' filming was that her mother's mental and physical condition remained fairly stable, while the real medical drama was Bourne's own. While filming she had breast cancer diagnosed, an event that brought into sharp relief the reversal of her role as her mother's carer. She minds terribly about this, as she minds the physical drudgery of caring for her mother and the fearful boredom of her conversation, as tedious and surreal as that of a toddler.

Not much is hidden in the film, from soiled incontinence pads to Bourne's pain when her mother can't recognise her (though she knows Holly). Ethel's story is that of the end time of a life from which marriage, independence, health and clarity of mind have all vanished. She is not the woman she was. And yet Bourne's portrait of her mother shows her still loved and loving, amused and amusing, still capable of feeling and provoking joy and pleasure as well as exhaustion and rage, still - above all - a personality. It is that remarkable thing: a true picture of what it's really like to grow old. Unless you're planning to die young, you should watch it.

One thing leads to another, and in the week in which Britain's first undergraduate degree in funeral directing was launched at the University of Bath, with a course offering instruction in embalming, burial at sea and how to comfort grieving relations (astonishing how we've contrived to dispose of our Loved Ones without academic instruction until now), I hasten to share with you the news of the Neptune Memorial Reef, an underwater cemetery off Miami that offers the perfect final resting place for those of an aquatic disposition.

Americans put the reef into grief
The Americans - as admirers of Evelyn Waugh's The Loved One and Jessica Mitford's The American Way of Death already know - are much better at exuberant memorialisation of the dear departed than the shifty and inhibited Brits (at least now that the glory days of our great 19th-century necropolises are past).

So on this memorial reef you can have your ashes mixed with special underwater cement and cast in a mould, which is then secured to the reef by a diver. There are themed areas, such as dance, music or sports - you could have your mortal remains fashioned into a concrete Stratocaster or a stony Sugar Plum fairy. There's room, apparently, for 125,000 remains. Hurry, while space lasts ...

Up with the lark
Back in the world of the living, the alarm clock is said to be close to extinction as most of us prefer to be woken by other means. Modern agents of wakefulness apparently include mobile phones, morning radio or TV, partners, children or pets. A muddy paw on the face is certainly a great way to greet the day. But missing from this list is the sound that has been getting me out of bed at first light for the past few weeks - the deafening twitter of the dawn chorus in the tree outside my window.

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