In 1374 the Abbot of Athelney had a good idea. He had been involved in a series of disputes with his westerly neighbour, the Dean of Wells, over flooding caused by the River Tone as it poured off the Dean's land on Curry Moor and Hay Moor and onto his own holdings on North and Salt Moors.
At that time the Tone wound its way through a gap between East Lyng and the raised ground at Athelney, 500 years earlier the site of Alfred's stronghold.
The abbot decided radical action was necessary. So he diverted the Tone southwards into a new, embanked channel and built a wall along the line of an earlier causeway, creating a 550-yard barrier to close the gap between the two sections of high ground.
Baltmoor Wall stands to this day. And just as well. For it is all that now protects Bridgwater from a cataclysmic flood. It holds back billions of gallons of water in a lake which reaches all the way to the outskirts of Taunton. The Environment Agency says even once the rain stops it will take 26 days to pump it all away.
The structure was strengthened in the 19th century and again in 2000/2001 after fears during floods in the late Nineties that it could fail. On the southern side of the wall the water is currently about 15 feet deep.
For the moment it is only being overtopped, with water streaming across the A361 and slowly engulfing homes in Moorland, Fordgate and surrounding areas. Were it to collapse, thousands of homes in Bridgwater would face the same fate. There would be damage on an unthinkable scale.
Here is a situation which makes last week's statement by Environment Agency chairman Lord Chris Smith (though he yesterday said he had been misquoted) that when it comes to flood defences the nation must choose between town and country appear all the more ludicrous.
Since being engulfed by a tidal wave of opprobrium from MPs and others, the Labour peer has been backtracking furiously, though his assertion that: "What I was indicating was that there are always difficult choices to be made because there isn't a limitless purse of money available, and we have to make decisions about where the most effective flood defences can be created – that will be whether it is in the town or in the country", suggests that he is digging the hole deeper still.
As to calls – led by Bridgwater and West Somerset Conservative MP Ian Liddell-Grainger – for him to resign, Lord Smith has dismissed them as "playing silly games".
What outraged and despairing flood victims on the Levels are beginning to believe, however, is that Lord Smith's choice between town and country has already been made – and that the country is the loser.
In other words, a former Labour politician has run true to form and decided the country really isn't important: the same philosophy which led to Labour allowing the TB epidemic to race out of control and failing to take foot-and-mouth seriously until the disease had been spread from one end of the country to the other.
Yesterday Lord Smith finally turned up in Somerset to inspect the consequences of one of the wettest periods of British weather on record – consequences which are immeasurably more severe because deep, broad river channels which would once have carried floodwaters away have become shallower and constricted because his agency halted dredging 20 years ago. Further evidence, if any were needed, that the decision has already been taken that town is more important than country.
Perhaps the most telling evidence for this, however, comes in a slideshow presentation the agency has produced on the very subject of dredging, a patronising, Janet and John guide to the whole business of river management.
At the heart of this piece of propaganda is its insistence that dredging is not the answer to floods because even when dredged river channels can never accommodate all the water resulting from extreme rainfall. It's also expensive.
That is not what the people of the Levels have been claiming. Their argument – and it is indisputable – is that the rivers now reduced to at best 60 per cent of their former capacity cannot drain the area rapidly enough when heavy rain does come.
They fill more quickly and as a consequence there is less capacity for water to be pumped into them and eventually the entire system becomes overloaded and backed up, precisely as has happened in the last few weeks.
The Somerset Levels have always flooded. The pollarded willows lining the roads were originally put there to delineate the carriageway for the benefit of horse-drawn traffic in winter. Bur people have still been able to live there. There have been very few mass evacuations.
What we are witnessing now is the result of the Environment Agency making a massive blunder: of selling off its dredging equipment and allowing rivers to silt progressively just as rainfall events were becoming more severe.
Of squandering tens of millions on grandiose schemes for nature reserves, fleets of vehicles, plush offices, overseas junkets and bonuses when a few million would have dredged Somerset's rivers and massively reduced the severity of this winter's catastrophe.
As its £110,000 a year, two-day a week chairman, Lord Smith has presided over this grotesque combination of profligacy and negligence. He may not have signed off every report, approved every action. But ultimately his is the responsibility.
His is the failing. It is he who will be remembered for wrecking homes, destroying businesses, putting people out of work, placing families under untold levels of stress – for putting town before country.
Which is why he must be removed from office now before he makes an even bigger mess of things.