LEVEES, EMBANKMENTS, DIKES FINDING COMMON GROUND BETWEEN THE FLOOD RISK MANAGEMENT CULTURES OF THE USA, ENGLAND AND THE NETHERLANDS ISFD4, Toronto 7 May 2008 Jaap Flikweert

Background Involvement in FRM in various countries  Notice differences  Why? Culture, Geography, History Or Coincidence? n No thorough scientific study… n …just discussions at the coffee machine n Work in progress! Thanks to Mathijs van Ledden (Haskoning Inc, New Orleans)

Lay out of presentation 9 Aspects: n Nature and level of flood risk n Legal arrangements n Role of insurance n How to manage the risk n Events driving developments n Dealing with future changes n Structural flood risk management n Asset management n Public perception of flood risk Conclusions

Nature and level of flood risk NL: n Defining feature, national issue n Infinite x Infinitesimal =? EN: n One of the important issues n Variability, regional issue n £ 1.3 billion / year (2005) (C$ 2.5 billion) USA: n One of the important issues n Variability, regional issue n $ 4.5 billion / year ( ) (C$ 5 billion) EN/USA more comparable graphic: USGS

Legal arrangements & funding NL: n Legal standards and roles n Ministry of infrastructure n €500 million  C$ 785 million EN: n Permissive powers (legal) n Department for the Environment (formerly Agriculture, Fisheries and Food) n £600 - £800 million  C$ 1.2 – 1.6 billion USA: n Insurance & certification n Department of Defense n $280 million  C$ 285 million (USACE, excl improvement works; New Orleans $15 billion) Very different; culture, but also history

Role of insurance NL: n None – 1953 event (  1.5 billion ~ C$ 10 billion) n The state in practice n Some debate EN: n Private insurance if < 1/75 per year n Important lobby  trigger for risk reduction USA: n Driving force, legal basis n Federal backed insurance n Impact on many aspects of flood risk management NL different due to geography & history. EN / USA: culture?

How to manage the risk NL: n History: structural (defences+source control) n Recent: evacuation & land use EN: n Combination of structural & non-structural n Emphasis on development planning USA: n Defence plus evacuation n Choice of measures driven by insurability General move to balanced portfolio

Events driving developments NL: n Throughout history n 1953 EN: n 1953: Thames defences & warning n 1998: change of focus USA: n 1927 Mississippi flood n Various hurricanes Now starting to learn from events elsewhere

Dealing with future changes NL: n Existential question n For now, technically solvable n Commissions at work EN: n Very explicit n Government led studies n Catchment & shoreline planning USA: n Sea level rise in design & strategy n NO: subsidence at equal rate Each in his own way

Structural flood risk management NL: n Legal safety standard n Detailed & complete guidance EN: n Indicative standards n Benefit / cost plus ‘Outcome measures’ n Limited guidance USA: n Up to 1% per year (insurance) n Certification requirements drive design Three different mechanisms

Asset management NL: n Large professional dedicated organisations n Legal roles, but ‘how’ is up to asset manager EN: n One national organisation n Detailed strict procedures USA: n USACE and others n Good management is criterium for certification n Guidance from USACE Paradox design guidance – rules for asset mgt

Public perception NL: n Paradox: awareness, trust & expectation n Recent changes f(Katrina, climate change) EN: n Growing awareness (events & communication) n Natural risk? USA: n Well aware n Limited confidence in authorities Strongly driven by events

Conclusions UK and USA more comparable; NL as extreme reference Optimisation problem Performance / Risk / Cost: n NL: fixed performance standard, minimise cost n EN & USA: fixed budget, minimise risk Each their own recipe for FRM, based on history, geography, culture Events as opportunities for readjustment? Invitation to extend analysis