Television is a medium that suffers congenital amnesia. Nobody remembers anything. I write this every two or three years. I write it because television is a medium that suffers congenital amnesia and nobody remembers anything. Actually, that’s not quite true. Tristrams refuse to remember the worthwhile. They just can’t forget, or can’t get enough of, the meretricious, embarrassing, brain-rotting drivel that they clone with obsessive-compulsive hysteria.

The constant problem with television is that the people who make it watch too much and too little. They see endless window-dressed plagiarism and nothing like enough from the past. So, each generation loses the experience of the previous one. They hand each other awards named for Flaherty, Grierson and Jennings, but have no idea who these people were; and they only know Ken Russell as a batty old end-of-the-pier ranter, because they’ve never seen his Delius or Elgar docu-dramas. They know Lindsay Anderson because of If..., but know nothing of the Free Cinema Movement or the dozens of documentaries he made. Saddest, perhaps, is that hardly anyone making drama or documentary will have seen the work of Peter Watkins. He was the Giorgione of television. Not much is known about him, and he didn’t make much, but what he did is superlative.

I thought about Watkins while watching Flood (Sunday-Monday, ITV1). Before the producers start phoning their mothers, let me say this is not going to be a pleasant review experience. You won’t want to share it. Watkins made a television documentary in 1965 called The War Game, about a nuclear attack on Britain. It was the first prototype disaster movie made for television. It was also banned for being too good, too realistic, too frightening, and embarrassing for politicians. So, now, a generation on, someone makes a four-hour film about flooding London, the global-warming, searising version of a nuclear attack, this century’s collective annihilation fear - and they’d learnt little or nothing. Everything that was chilling and gripping and brilliant about The War Game was sodden, flabby and attention-sapping in Flood. All its inspiration, all of its timing tricks, dialogue and truncated emotion came not from previous television, but from Hollywood disaster movies. It was Titanic, out of The Day After Tomorrow, by way of The Perfect Storm. Why would anyone want to do that? Why would you, as a writer, director or producer, want to imitate a risibly ridiculous, kitsch and clichéd, overblown, knuckle-headed genre that relies on a screen 20ft wide with 40 decibels of Dolby and a flotilla of special effects that cost the GDP of Kuwait? Why would you imagine that that’s going to be entertaining, engrossing or worthwhile on a TV set? More depressing than television’s genuflecting adaptation of 19th-century novels is its adaptations of 1990s American movies. The news of a real natural disaster hitting Burma may have made the publicists think it gave this shoddy farrago a topical poignancy and a bit of edge, but, actually, it simply made it even more puerilely tasteless.

It would be a poignant litany of catastrophe to point out all the things that were wrong with Flood. Let’s just say that with true disaster-movie predictability, everything that could go belly-up went belly-up, from the frantic camera and editing to the all-star cast desperate for the anonymous water to close over their career-shaming performances. Robert Carlyle, as the small-screen Bruce Willis, finally washed away all the kudos of Trainspotting and The Full Monty. But saddest of all was Tom Courtenay, all at sea with a look of self-inflicted dementia, desperately trying to pretend none of this was happening. He will know all the names referenced above. He made The Loneliness of the Long Distance Runner, when British drama and documentaries shared a common view and were about something, something else entirely, something we’ve forgotten.

David Attenborough complained recently that there were too many copycat programmes on television. He’s someone you might think would want to do the voiceover for a programme about copycats. He said there’s too much cooking, too much property, too many makeovers, while television can’t summon up a single decent weekly strand on science or classical music or indeed any sort of music. The interests of the nation are apparently reduced to getting fat and getting a sofa to be fat on. He has a point.

This week, we got Grand Designs Live (Sunday-Friday, C4), one of those programme titles Alan Partridge used to think up - an irony that gets made as reality. It was, as he might say, quite literally, watching paint dry in real time. I have never really understood television’s devotion to live broadcasting. Who would want to watch live writing or live cinema? At the beginning, I loved it, because it was a technical feat. I can remember the first transatlantic broadcast, when we were shown Times Square in New York, which might have been Manchester in real time. It seemed an earth-shrinking moment, but it was the idea, rather than the content, that excited. Now, live broadcasting is nothing special, but still editors thrill to the idea of it. If your format needs to be live to be gripping, then it probably wasn’t a very good idea in the first place. Three-quarters of the worst programmes ever made were live, and this one, six days of turgid dross, jumps right onto the cringing heap.

The central bit of the programme, a competition, wasn’t live at all. You had to phone in and vote for a house. Who could care? Who has an opinion about three young smug marrieds’ bathroom suites? Leaving aside the jerry-built extension of the live element, the fundamental problem with Grand Designs is that the buildings and the rooms are so relentlessly repetitive. They’re all as similar as Lego. It isn’t a celebration of remarkable innovation or aesthetic excellence; rather a repetition of tired and tentative received quite-good-taste. The decorations of these rooms all looked like provincial businessmen’s hotels and Habitat windows. Their predictability is only surpassed by the paucity of the vocabulary used to describe them. The language of design is little more than the empty exclamations and threadbare phrases of estate agents’ particulars. Architecture deserves a great deal better than this Pooterish advent calendar of swish little lives. And just as the housing market collapses and half the people watching are waiting sleeplessly for the next mortgage demand, all the good taste seems deeply tasteless.

And, finally, not because I give a damn, but just because I’d like to know: if you have a phone-in competition and you begin taking votes after showing the first contestant and finish a few minutes after showing the last one, doesn’t that mean that being last is a distinct disadvantage? I only mention it because I know lots of people get very excited about phone-in competitions. There are weeks when I despair of television. I would have had difficulty arguing with all those arty prats who say it’s all sop and pap, noise and light for living rooms. I even missed the week before’s Embarrassing Diseases. Staring up some deranged lady’s frilly front bottom would have been more honestly entertaining than this week’s sad flash.

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