Embed Size (px)
Citation preview
www.cranfield.ac.uk
Flood risk management and incident response in practice
Professor Paul Leinster CBE
July 2017
Flood
forecasting
Modelling Mapping
Policy Governance
Weather
forecasting
Development
control
Operation
Environmental
protection
Maintenance
Capital
schemes
Informing Warning
Monitoring
Exercises
Roles, accountabilities,
responsibilities
Recovery Incident
response
Compensatory
habitat
Components of a flood risk management programme
o Early December surge
o 12 major winter storms between mid-December and mid-February
o Prolonged periods of heavy rain, gale-force winds, tidal surges and large waves
o Wettest winter in England for nearly 250 years
o Many areas received 200% of average rainfall
o Lowest depression recorded in UK since 1886
December 2013 to February 2014
Lessons to be learned from every flood event
Mapping, forecasting and warning
Think big,
act early
Properties flooded and properties protected
Groundwater flooding
River flooding, Morpeth
Surface, ground, fluvial or coastal flooding and do people care?
Surface water flooding
River flooding
Coastal flooding
Infrastructure at risk
o Hospitals
o Care homes
o Police, ambulance, fire stations
o Control centres
o Transport
o Water and sewage
o Electricity substations
o Schools
o Telephone exchanges
Improvements between 2007 and 2014
No. of properties flooded in:
2007 2014
Thames at
Oxford
350 <50
Lower Severn
1560 (fluvial
only)*
220
July 2007 February 2014
Practical interventions
A tale of 2 shop keepers
o 2009
o 2015
o 20??
o Business continuity
o Resilience
Communications
Communicating about risks can be tricky
5yrs 10yrs
5% 10%
25yrs
22%
Cheltenham 2006
£22m flood risk
management scheme
completed
Cheltenham 2007
Land management
based approaches
95 Barlow et al 2014 Working with natural processes to reduce flood risk
National Infrastructure Commission 2017
Land management based approaches
53 Dadson et al 2016 Natural Flood Management Reinstatement
National Infrastructure Commission 2017
When will a new Thames Barrier be required?
o 50 closures in 2013 – 2014 winter – over one-quarter of all closures since completion in 1984
o 6 December 2013 – highest tide since completion
Thames Estuary: using scenarios and a managed adaptive approach
New barrier
(2070 - )
Today
+0.5m
+0.2m
Improve
defences
(2040 - 2070)
Maintain
defences
(now - 2040)
1-
in -
1000 y
ear
flo
od
Why do people do it?
1581m
m
Legend
Groundwater Level
! Highest recorded
! Exceptionally high
! Notably high
! Above normal
! Normal
Rivers. Monthly Mean
Highest recorded
Exeptionally high
Notably high
Above Normal
Normal
What does the future hold: February 2014
Based on provisional NCIC data. % of Long Term Average
December 116 mm
(4.6 inches)
January 158 mm
(6.2 inches) February 120 mm
(4.7 inches)
140% LTA 200% LTA
212% LTA
Rainfall
River flows and groundwater
1581m
m
Legend
Groundwater Level
! Highest recorded
! Exceptionally high
! Notably high
! Above normal
! Normal
Rivers. Monthly Mean
Highest recorded
Exeptionally high
Notably high
Above Normal
Normal
What does the future hold: February 2014
Based on provisional NCIC data. % of Long Term Average
December 116 mm
(4.6 inches)
January 158 mm
(6.2 inches) February 120 mm
(4.7 inches)
140% LTA 200% LTA
212% LTA
Rainfall
River flows and groundwater
.. new record levels –
December 2015
and
.. new record levels –
month 201?
Until
Acting on what we do know
o Climate
o Extreme weather
o Development
o Population increase
o Infrastructure impacts
