Flood Risk Management - Example from the FRMP Fulda

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1 Universität Kassel Fachgebiet Wasserbau und Wasserwirtschaft Univ.-Prof. Dr.-Ing. Stephan Theobald Flood CBA meeting, Bucharest, 25. Sep Flood Risk Management - Example from the FRMP Fulda Department of Hydraulic Engineering and Water Resources Management -Institute for Water, Waste and Environment (IWAU) Faculty of Civil and Environmental Engineering University of Kassel Univ.-Prof. Dr.-Ing. Stephan Theobald Dr.-Ing. Klaus Träbing 1

2 Flood protection strategy Flood area management - area precaution - natural water retention in the area Technical flood protection - construction and operation of retarding basins - construction of dams, dikes and flood walls - construction of polders - storage management of dams - mobile flood protection facilities for single objects Flood prevention - operational use (information and precaution behavior) - building precaution - risk provisioning 2

3 Cycle of Flood risk management - 1 Cyclic process: Association between coverage, regeneration and precaution against flood risks in connection with the relevant areas of action; all phases before, during and after a flood are included. Significant emphasis is laid upon the exchange of expertise and the involvement of affected communities, representatives of public interests and the interested public. encompasses the entire precaution-, emergency responseand follow-up cycle Reference: LAWA 2010, translated, See also FLINKMAN 3

4 Cycle of Flood risk management - 2 Examples for preparedness in precautionary behaviour and information: Large inland rivers dominated by slow rise of floods with good predictability during event due to reasonable hydrological observational network, information publicly available by www Small streams and flash-floods dominated by thunder-storm-like events with predictability only for the basic expectation of strong rainfall events, information publicly available by www Examples for Technical flood protection in frequent practice: Single-purpose-projects mainly in reconstruction measures, e.g. levee reconstruction incl. accompanying measures like installation of pumping stations Multi-purpose-projects, mainly in combination with ecology-targeted stream and/or floodplain restoration measures Assessment of FRM-measures in frequent practice: Designs of Technical constructions cover economic analyses and environmental impact assessment incl. ecological, social and economic effects on a rather approximate level Accompanying measures like public information: no special information 4

5 Costs and benefits - 1 Costs and benefits in WRM / FRM (1): Net Present Values (depreciated values) are used VAT is usually included in economic calculations since it is not basically different from other financial flows (transfer payments) of uncommitted taxes or fees (e.g. income tax, real estate transfer tax or subventions) which may be assumed to be necessary to run an economy embedded into a society and its political system. So VAT as well as similar financial flows are not only considered from an individual view but also from a public standpoint of the national economic as a whole. Cost-Effectiveness-Analyses (CEA): Costs and benefits are always considered to find the best alternative for the same pre-assigned benefits; costs expressed in monetary units concerning investment, maintenance and deconstruction reserve; benefits considering multi-purpose-aims and restrictions like design flood or restored stream reach etc. 5

6 Costs and benefits - 2 Costs and benefits in WRM / FRM (2): Cost-Benefit-Analyses (CBA): widely used in Water Resources Management for economically dominated decisions like the determination of discharge of design in hydro power or selection of the system of waste water treatment. Damage-functions were explored in databases (e.g. HOWAS) which are not always kept actual Long life cycles, escalator effects and lacks according to the principle of equality (not same, but equivalent living conditions; Art. 72, GG) may be a reason for a relative low confidence in economic calculation (e.g. effect of interest rates, shifting beliefs and preferences in society, historical changes) 6

7 Costs and benefits - 3 Costs and benefits in WRM / FRM (3): Decision-making responsible bodies in FRM ( at the end of the project-chain ) usually targets on given design-criteria like 100-yr-flood (HQ 100 ) Design criteria are the result of a social-economic consensus based on generally recognised codes of practice (allgemein anerkannte Regeln der Technik: aardt; always considering additional aspects and criteria; maybe: might be interpreted in the sense of a Willingness to Pay economic approach) It is reasonable to assume and often observed (but not intensely reported yet in Germany) that flood protection measures (FPM) increase the intensity of use in the protected area resulting in increased damage and non-reliable results for long lifecycles of the FPM ( escalator effect ) 7

8 European Directive on the assessment and management of flood risks objectives and milestones: Preliminary Flood Risk Assessment timetable Flood hazard maps 3 flood-scenarios: - low, medium and high probability key elements: - the flood extent - water depths or water level, as appropriate Flood risk maps - indicative number of inhabitants - economic activity of the potentially affected area - installations which might cause accidental pollution - potentially affected protected areas Flood risk management plans 8

9 FRMP Fulda - planning process and measures basis: catalogue of the types of measures (description, references, etc.) Maßnahme Hinweise und Bewertungen 1 Flächenvorsorge administrative Instrumente 1.2 angepasste Flächennutzung 2.1 Maßnahmen zur natürlichen Wasserrückhaltung 2.2 Reaktivierung von Retentionsräumen 3.1 Stauanlagen zur Hochwasserrückhaltung im Einzugsgebiet 3.2 Deiche, Dämme, Hochwasserschutzmauern und mobiler HW-Schutz 3.3 Maßnahmen im Abflussquerschnitt bzw. Erhöhung der Abflusskapazität 3.4 siedlungswasserwirtschaftliche Maßnahmen 3.5 Objektschutz 3.6 sonstige Maßnahmen Hochwasservorsorge 4.1 Bauvorsorge 4.2 Risikovorsorge land use (8 types) Natürlicher Wasserrückhalt natural retention (11 types) Technischer Hochwasserschutz technical flood protection (19 types) flood prevention (11 types) 4.3 Informationsvorsorge 4.4 Verhaltensvorsorge Beschreibung der Maßnahme (Defizit, Wirkung, Umsetzung, pot. Maßnahmenträger, etc.) Hinweise zu Hochwasserschutzwirkung, Umsetzbarkeit, Akzeptanz, etc. Einfluss auf Umweltgüter Einfluss auf Nutzungen Bezug zur WRRL 4.5 Vorhaltung, Vor- und Nachbereitung der Gefahrenabwehr 9

10 FRMP Fulda - planning process and measures visualisation of the proposals to optimise the flood risk management with the help of a GIS-Project water depth of a 100 year flood link to the profiles of measures proposals of measures (located) documentation of a site visit proposals of measures (not located) existing dykes 10

11 FRMP Fulda - products and results What are the essential products of the FRMP for the Hessian river basin of the Fulda? GIS-Project with all the data and background information flood hazard maps for the main rivers explanatory report profiles of measures and database to document the planning process flood risks maps for the main rivers example for Hesse: - data management - depth of planning 11

12 Costs and benefit in FRMP Fulda - 1 Basics from FRM-Directive concerning cost (18) Member States should base their assessments, maps and plans on appropriate best practice and best available technologies not entailing excessive costs in the field of flood risk management. Chapter IV (Flood risk management Plans), Article 7, Paragraph 3 (Sentence 2): Flood risk management plans shall take into account relevant aspects such as costs and benefits, flood extent and flood conveyance routes and areas which have the potential to retain flood water, such as natural floodplains, the environmental objectives of Article 4 of Directive 2000/60/EC, soil and water management, spatial planning, land use, nature conservation, navigation and port infrastructure. Annex A. Flood risk management plans I. Components of the first flood risk management plans: ( ) 5. when available, for shared river basins or sub-basins, a description of the methodology, defined by the Member States concerned, of cost-benefit analysis used to assess measures with transnational effects. CBA is neither requested nor excluded 12

13 Costs and benefit in FRMP Fulda - 2 FRMP Fulda: Eine ausgesprochene Nutzen-Kosten-Untersuchung ist nicht notwendig. Dennoch geben Betrachtungen zum Aufwand und Vorteil von Lösungsansätzen zur Verbesserung der Hochwassersituation Hinweise zu geeigneten bzw. effizienten Maßnahmen an die örtlichen Planungsträger. (Hochwasserrisikomanagementplan Fulda, S. 6) An explicit Benefit-Cost-Analysis is not necessary. Nevertheless viewing on effort and gain of approaches to improve the flooding situation give hints on appropriate resp. efficient measures for local planning authorities. 13

14 Costs and benefit in FRMP Fulda - 3 FRMP Fulda: results of effort and gain -approach 14

15 Selected further examples in Germany Reference: Kron, A., 2008: Mikroskalige Ermittlung potenzieller Hochwasserschäden zur Gefahren- und Risikoanalyse CBA in WRM and FRM is widely known and may be applied CBA is considered as one possible element for assessments in FRM BWK 2001: Hochwasserschadenspotenziale. Bericht 1/

16 Topics to discuss for Flood-CBA to increase acceptance in practice Basics Consideration of multi-purpose-projects Consideration of MCA: will probably not increase acceptance Consideration of simpler methods like effort and gain Details Consideration of transfer payments as part of external social costs Concretion in terms of indifferent results due to uncertain economic conditions (e.g. interest rates, life cycle) Inclusion of escalator effect : reality in economics 16