In the knowledge that Canvey Island sea defences were constructed to a 1 in 1000 year storm event standard, whilst the Dutch defences are designed to withstand a 1 in 10,000 year event, it was concerning to note the current condition of part of the defence.
The Sort Our Seawall article headlining the Echo Newspaper, weds 20th Nov. has once again highlighted the fact that the Canvey Island sea defence is not a luxury.
It has indeed became the very structure that our lives and wellbeing totally depends upon, given that the only emergency plan devised is a Go in- Stay in –Tune in, strategy .
It is therefore imperative that’s its maintenance and indeed programmed improvement, is properly funded.
The responsibility for funding remains at the door of DEFRA whose budget is increasingly being stretched by the Environment Agency’s demands.
The 2008 Integrated Flood Risk Analysis document, Co-funded by the European Community, linked with the Thames Estuary 2100 project, commented that at present Canvey Island is protected by a concrete sea wall that rises approximately 3m to 4m above high tide level. It has been found that whilst substantial, these defences show signs of deterioration such as cracks in the concrete, and the degradation of seals between slabs. Metal access doors also represent weak points with imperfect seals around them, bolts have to be manually placed to shut the gates with bolt holes being prone to getting blocked with debris.
The document went on to say that: It is estimated that the current standard of protection at Canvey Island of 0.1% (1 in 1000 years) event scenario will be reduced to 0.5% (1 in 200 years) by 2030.
It is estimated that 30% of dwellings on Canvey are bungalows with the increasing number of flats with ground floor accommodation being developed, this along with an ageing population represents a large risk to life should there be a situation of limited opportunity to temporarily move people out of the predicted flood level brought about by a failure or breaching of the sea defence.
Compounded by the logistics of a search and rescue reactive emergency plan highlights the necessity to question the aspiration of Castle Point Council to allow for further large scale housing development of Canvey Island.
It would not be unreasonable to expect that having gained the knowledge that our sea defence no longer represents the best in the country and its longevity is now calculable that the two County Councillors featured within this article should strongly object to future large-scale development on zone 3 flood plain at Canvey Island.