Flooding at Mersea Island the morning after the Great Tide. (Photograph courtesy of Brian Jay)
Andy Blowers asks what might happen at Bradwell if the East coast floods again as in 1953 in the BANNG Column for Regional Life July 2019.
‘It was now that wind and sea in concert leaped forward to their triumph’
(Hilda Grieve, The Great Tide, 1959)
During the night of 31 January/1 February, 1953, in the moonlit dark, dead heart of winter, the Essex Coast was struck by a surging storm, flooding the creeks, overpowering the sea defences and leaving a trail of disruption, destruction and death in its wake. I recollect my own astonishment when walking to church that Sunday morning at the sight of the flooded factories of the Hythe at Colchester. I wonder what might happen to the low-lying lands around the Blackwater if such a storm surge occurs again and if, heaven forbid, a new nuclear power station had been built at the Bradwell site.
Throughout the previous day, a Saturday, a deepening depression, its centre at 972mb., code named ‘LZ’, was working its way across the British Isles. A very high tide was building as the winds, veering north and gusting up to hurricane force, pushed the feebly ebbing water on to the East coast, into the narrowing shallow basin of the southern North Sea. Long before high tide was due, the waters had risen well above expected levels. At 10 p.m. the level at Harwich, three hours before high tide, was already 6 feet higher than it should have been.
Essex was largely ignorant of what had been happening elsewhere during that day where vessels had sunk and coasts had been battered and people drowned. As The Great Tide struck moving southwards, one by one the coastal communities, unbeknown to each other, felt its force and harrowing consequences. At Harwich the sea came in from three sides drowning those unable to escape its rapid ingress. The highest death tolls were at Jaywick, where 37, were killed and Canvey Island, where the toll was 58, and the tide came in by stealth round the unprotected back of the island, drowning some lying upstairs in bed as the waters rose. Altogether there were over 300 deaths in England, though far fewer than the Netherlands where more than 1,800 died.
[Photograph of the flooded Strood around here. Caption: Flooding at Mersea Island the morning after the Great Tide. (Photograph courtesy of Brian Jay)]
The low-lying Essex marshes and coastlands were inundated. Mersea Island was cut off for around five hours (10.30 p.m. to 3.30 a.m.) as the Strood was covered by 7 feet of water at high tide (see photograph). The creeks of the Blackwater filled and breaches in the sea walls made the marshlands into sheets of water. At Bradwell, as Hilda Grieve, the chronicler of The Great Tide, observed: ‘the open sea suddenly seemed to rear up in the distance, surging forward towards the covered saltings and the wall in a great wave, several feet high’. Around the Dengie, the sea walls were breached at several points, including Bradwell. As the waters spread cattle had to be rescued, though some drowned, and farmhouses and buildings ‘stood isolated, their dark windows staring out over the moonlit watery wastes spreading silently in the fields around them’.
A landscape at risk
It seems hard to imagine the devastation and fear of that long night, long ago. Since then, the former nuclear power station, Bradwell A, has come and gone, though its radioactive reactor cores remain, menacing but innocently hidden within the grey blue clad buildings. Over the years, sea defences on the Dengie have been strengthened, warning systems put in place and emergency plans have been developed.
If it ever comes to pass, a new nuclear station at Bradwell would generate power for around 60 years, until the end of this century. Once shut, dangerous, highly radioactive spent fuel and other wastes will remain on the site indefinitely, certainly until the later part of the next century. It would be heroic to claim that the site could be protected from the catastrophic impacts of climate change during that long period.
With current defences there is a 0.5% (1 in 200) chance per year risk of the site flooding to 3 metres. For an area of farmland that may seem a risk worth taking. But, as the site for a new nuclear power station, it would be perverse to take such a risk with the catastrophic consequences that might ensue.
If present trends continue, a rise in sea level of 2 metres by 2100 is plausible. Beyond 2100 forecasting becomes difficult. But, under certain assumptions it is not inconceivable to envisage at the extreme a 7.5 metre rise in sea levels by 2200 if global temperatures rise by 50C. Such figures are truly alarming but cannot be unthinkable and, therefore, must be planned for in the unknowable conditions of the next century.
What must be recognised is that, with global warming and rising seas, destructive storm surges, flooding and coastal erosion are quite likely events over the lifetime of a new nuclear plant on the vulnerable shores of Bradwell. In the circumstances it is difficult to conceive how the site can be considered potentially suitable now, let alone into the next century when decommissioning and radioactive waste management will become hazardous operations.
In Hilda Grieve’s words, memory of The Great Tide
‘will grow dim as the years pass. But the sea will not be tamed. From
time to time, urged on by its only master, the wind, to break the order
of its course, it will rise again to strike the land’.