The tidal surge which hit the east coast of Britain in early December 2013, was considered the “most serious” for 60 years, as not since the floods of 1953, have we seen sea levels at a height which threatened homes and infrastructure from the Wash to Sandwich. Unlike 1953, because of extensive flood defence work, we are now better prepared and defended against extreme tides and water levels, but flood risks do remain.
What caused the December 2013 tidal surge? Three factors combine to the surge effect. First there were very high “spring” tides; secondly, low pressure in the North Sea caused water levels to further rise and lastly, strong northerly on-shore winds tend to funnel tidal streams into the relatively enclosed shape of the North Sea. Although the worst effects were felt along the East Coast, as in 2007, we saw an adverse impact in the English Channel coast as far as Rye Bay.
With Rye at the confluence of three rivers and under tidal influence, water levels are always of concern, but in recent years, flood defences have been greatly improved with raised and improved river and sea walls, fitted with flood gates on access points. Before any forecast extreme tide, Environment Agency teams close the flood gates and drop the river levels on the Brede and Tillingham to cope with river flow.
On the night of 5/6 December high tide was forecast for around midnight at a level of 4m, but for an hour afterwards the sea surged to a new high: 5.1 m at the Rye Strand ramp opposite the River haven Hotel. At its peak, the water rose about half way up the flood walls/gates at the Strand and apart from some seepage through one or two weak spots, the system held. In the Rock Channel, some workshops and garages on the river side of the defences tosements of the houses at Rock Channel Quay are designed to be part of the river wall and also flooded. There were two issues at Rye Harbour, first a flap cover on a drain outlet failed to seal properly allowing water into within a metre or so of houses, secondly the extreme flows washed away part of the coastal path and flooded the Rye Harbour Reserve cottage.
The event showed that when the flood defence system works, even under surge conditions, the risk to Rye is managed, but if any part of the infrastructure fails then quickly, the situation can worsen, with homes and businesses threatened.
Colonel Anthony Kimber, who leads the voluntary Rye Emergency Community Action Team (REACT), emphasises “that the conditions which give the most concern are when there is a combination of several factors: spring tides with a surge of water on top; conditions where there are strong on-shore winds; heavy rainfall causing saturated ground and high river levels. These combine to test the flood defence system to its limits. That is why in times of budget cuts, continued maintenance of the key parts of the sea and river defence infrastructure remains vital.” He goes on to say that “these conditions also highlight the need for adequate national arrangements to underwrite home insurance in flood risk areas, so that residents can have peace of mind if the worst happens. There are ongoing and protracted negotiations between government and the Association of British Insurers, but no agreement as such.
For those who live or work on the flood plain (shown on the Environment Agency risk map) in times of extreme weather it is important to listen to the Met Office forecasts and Environment Agency warnings. These are designed to “Alert but not Alarm”. At times of high risk, occupants should also be prepared to react to the instructions from the Emergency Services and Local Authorities, responding to any events.
REACT continues to work with the professionals, including the Environment Agency to press for flood defence improvements before any event and, in the event of a failure, to be prepared to add value to the multi-agency contingency plans, by providing local advice, help with communication and the identification of community resources. We are often asked about flood risks around Rye, particularly where development has taken place on the flood plain. There are risks and when the system works they are mitigated, but if there are failures, human or technological, then there are contingencies in place to deal.”
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