Where can I launch my surfboard!
Managing the 5th December 2013 tidal surge
The bi-annual River Deben Association talk was delivered by David Kemp, Coastal Team Leader, Environment Agency (EA) to an audience of over 100 members.
When a flood is forecast, the key time is the preparation within the 24 hours before the storm arrives. His fascinating account took us through the EA’s planning in the East Anglia Incident room whilst preparing for the surge of 5th December 2013.
The EA Incident Room (based in Ipswich) is concerned with a range of issues, including shipwrecks, radiation, drought, foot and mouth outbreaks, and flood management.
Through constant analysis of tides and data, its forecasters must take into account: the strength of the surge, whether its timing coincides with high tide, and a phenomenon that occurs in the North Sea called ‘amphidromic points’ – which operate like spokes of a wheel, with waves spinning off the “spokes”, contributing to the surge.
Suffolk has 12 flood alert areas and 40 flood warning areas. Particular areas of concern along the Deben include: Bawdsey Ferry, Martlesham Creek, Methersgate, Felixstowe Hamlet, and Shottisham.
A major task is communicating with the public. An increasing issue is the effect of social media, for example members of the public may go out looking for floods. Before the flood surge in 2013, one man wanted to know the best place to launch his surfboard! Sometimes road blocks are needed to maintain safety.
Countdown: the day before the surge
At 6.00 a.m. on the day before the surge, the tidal data is analysed to assess the impact on different areas.
The evening news cycle begins by 4 p.m. so that communities understand the likely impact on their area. Many people won’t evacuate without their pets.
The day of the flood – 5th December 2013
By 6.00 a.m., a severe flood warning is issued, which results in increasing press queries. By 9.00 a.m. the Cabinet Office is briefed. Pumps and barriers are deployed.
2.00 p.m. is the last forecast where the team can take action. VIP visits are arranged, which need logistical support. As the surge passes through, staff have already been deployed to the coast to observe and monitor actual tidal flow, and flight observations are organised.
By 5.00 p.m. the press are clamouring for news and the first press conference is held in Wells – the first area to be hit. At 7.30 p.m. the tide arrives with the increased power of the surge; it takes 7 hours and 45 minutes to pass through the area. Although there was damage, there was no loss of life within East Anglia.
The rising sea levels in the last 10 years mean that there is an increased risk of low level flooding. More resources will need to be deployed to minimise damage. But compared with the Netherlands we should consider ourselves lucky; in the event of severe flooding, their nearest point of safe evacuation is to Germany.