Referat:

1
Abstract
In August 2002 Germany and particularly Saxony
were hit by three consecutive severe floods
affecting practically two thirds of the State
territory. This disastrous flood event gave rise
to reconsider and redirect flood protection and
related disaster management in Saxony. An
entirely new strategic approach was developed.
Primarily, any reconstruction and flood
protection measures are based on holistic Flood
Protection Concepts (FPC) for all relevant
rivers. In these concepts, more than 1600
individual flood protection measures were
proposed and 548 flood risk maps for all
communities at risk were elaborated. With a new
methodology specially developed for this task,
all measures were prioritized, and a Flood
Protection Investment Programme (FPIP) with
considerable financial resources was put into
operation. Furthermore, a new facility
Landeshochwasserzentrum (State Flood Centre)
was set up, became operational in 2004 and
established an advanced full coverage forecast
and alert system, which already demonstrated its
reliable performance during recent floods.
2
The Saxon approach

• August 2002 torrential rains in Bohemia/Ore
  Mountains of up to 340 mm per day (highest ever
  recorded values in daily precipitation for
  Germany) caused floods in the Elbe river and its
  tributaries unprecedented in written history in
  Saxony
• Losses and damages
• 21 fatalities
• 25 000 houses, hospitals, kindergardens
  damaged (400 destroyed)
• 12 000 immediately affected enterprises
• 740 km destroyed or heavily damaged
  roads
• 20 destroyed or heavily damaged railway
  network
• 466 destroyed or heavily damaged
  bridges
• 280 damaged social facilities
• 11 of all schools and 233 sports clubs
  damaged
• 10 of all hospitals evacuated
• Heavy damage affecting cultural
  facilities and monuments
• Overall damages 6.2 billion Euro

3
Premisses
4
This was nothing entirely new of course, but
outlined the framework of future action in this
field. Consequently, Saxonys flood protection
strategy had to be readjusted
5
The implementation of this strategy is based on
following pillars

• A sustainable reconstruction after the 2002 flood
  disaster by taking into account future flood
  protection requirements at this stage already.
• The development and implementation of necessary
  flood protection measures (FPM) based on an
  comprehensive in-depth analysis comprising the
  whole river length and the entire catchment area.
  For all relevant Saxon rivers river basin based
  Flood Protection Concepts (FPC) had to be
  elaborated (47 concepts in total including the
  Saxon part of the Elbe). Basic content of these
  concepts

• Analysis of extreme floods in the recent past
  and comparison with further
• historic floods
• Hydrological analysis of rainfall-runoff
  processes and hydraulic modelling
• of flood propagation
• Identification of current protection level and
  damage potential

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• Derivation of differentiated protection levels
  depending on flood probability and damage
  expectancy values
• Flood hazard maps with a scale of 15000 for
  relevant events (HQ 20, 50, 100 and extreme
  floods)
• Reference values

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3. Second Law Amending the Saxon Water Law of
09/08/2004

• Main content
• Enhancement of flood prevention and protection
  planning, especially by
• introducing river basin-based FPC into
  legislation
• Improvement of water retention and runoff
  conditions, especially by
• special permit conditions for construction
  measures in flood formation
• areas
• Improved maintenance of dykes and reservoirs,
  especially by legally
• specified maintenance obligations and transfer
  of a number of reservoirs
• from municipal ownership to the State Dam
  Administration.
• Enhancement of public information on flood-prone
  areas, especially by a
• legal obligation to register such areas in the
  land register and to publish
• hazard maps.

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4. Furthermore, the Saxon flood alert system was
completely reorganised and modernised.
Cornerstones are

• concentration of responsibility for situation
  analyses, flood forecasting and flood alert
  messages at a single facility, the
  Landeshochwasserzentrum (State Flood Centre).
  This centre was set up, became operational in
  2004 and established an advanced full
  coverage, redundant and reliable forecast and
  alert system
• reorganisation of data and messages
  dissemination system, now including direct
  information transfer to all authorities with
  responsibilities in flood defence and selected
  private enterprises and a publicly accessible
  website with all relevant information
  (www.hochwasserzentrum.sachsen.de)
• upgrading of a close cooperation including
  precisely defined interfaces with the
  disaster management authorities
• urging and assisting municipalities in
  establishing flood defence brigades.

9
State-wide Prioritisation of FPM at Saxon Rivers
- Criteria and classifications (SOCHER et al.,
2005)
10
Results of State-wide Prioritisation of Flood
Protection Measures
11

• The results of this procedure provide a valuable
  input for a comprehensive Flood Protection
  Investment Programme (FPIP) which was put into
  operation with considerable financial resources,
  starting with the Saxon State double budget
  2005/2006.
• Included are financial resources of the European
  Regional Development Fund. Up to 2008, this
  investment programme is financed with about 340
  million for public flood protection
  investments.
• For a mid-term planning horizon of seven years,
  in total around 500 Mio are currently
  envisaged.
• The programme is progressing according to
  schedule and has proven its necessity during the
  spring flood in 2006.

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Integrated Water Reservoir Management
Multifunctional dams/reservoirs with adaptive
management Functions Hydropower, flood
protection, fishery, water supply, tourism,
navigation, ecology Adaptive Management

• Flexibility between functions
• Seasonal flexibility
• Reaction on threats such as flood and drought
• Integration into larger schemes such as cascades,
  river basin management
• Integration of up-stream and down-stream
  interests
• Differentiation between strategic and operational
  time scale

13
Flood Spring 2006

• HQ 20 for the Elbe River with strong impact from
  Moldau/Vltava
• Key actions and conclusions
• Predicted flood with origin in Bohemian Mountains
• Working early warning system between the riparian
  states
• Escalation of disaster management activities
  along the Elbe
• Precise operation of dam cascade along the
  Moldau/ Vltava
• Flood Risk Management in order to minimise threat
  and damage
• Extensive use of CR internet platform for flood
  risk management in Germany with immediate access
  to relevant information
• Strong will for co-operation according to the
  spirit of ICPE

14
Current Approach in Germany Flood hazard
map guidelines of the German Working Group of
the Federal States on Water Issues Overview
(Bund / Länder-Arbeitsgemeinschaft Wasser (LAWA))

• Recommended structure of flood hazard map
  projects
• Project definition data inventory and
  requirements analysis
• Definition of the relevant topography
• Hydrology and hydraulics
• Map production
• Public information measures

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1. Project definition data inventory and
requirements analysis Define the organisational
chart (concerning responsibilities, public
relations, data collection activities) Define
investigation area Verify available data and
identify data gaps Estimate cost and effort for
data collection and processing
2. Definition of the relevant topography Survey
the watercourse Define all basic essentials for
hydraulic analysis (cross sections,
engineering structures ...) Create terrain
models (by photogrammetric analyses or laser
scanning)
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3. Hydrology and hydraulics Create numerical
model for hydraulic analysis Carry out
hydrological calculations Determine water
levels, velocities and flooded areas
4. Map production Produce flood hazard maps
according to standardised layout specifications
5. Public information measures Publish and
distribute the maps Training for map use, i. g.
workshops
17
Potential flood hazard map users

• Water management agencies
• Regional/land use planning agencies
• Local planning agencies
• Disaster and emergency planning agencies
• Insurances
• Stakeholders affected by flooding

18
Examples of Flood hazard map features
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Further Implementation of the European Flood
Risk Management Directive in Saxony

• Rivers in State Responsibility
• - Adaptation of the hazard maps from
• the 47 Saxon FPC into flood
• risk maps
• - Adaptation auf the 47 Saxon FPC-flood
• protection measures into flood
• management plans
• - further implementation of Saxon Flood
• Protection Investment Program

• Rivers in Municipal Responsibility
• - preliminary flood risk assessment
• - Preparation of flood hazard maps,
• flood risk maps and flood management
• plans for the assessed river basin
• districts (including available hazard-
• maps and flood protection measures)
• - further implementation of municipal
• flood measures

- transnational coordination of river basin
districts, flood management plans and flood
measures
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Transnational Coordination - Outlook

• Bringing into force the laws, regulations and
  administrative provisions necessary to comply
  with the FRMD before 26/11/2009
• Cooperation on River Basin and transnationally
  shared River Basin level
• Continuation of technical work on Länder level
  with a view on Article 13
• Continuation of technical work on HARM for
  coastal areas with a limited scenario
• Integration of HARM into Disaster Management
  systems
• Forward integration with air/ space based
  monitoring technologies/ systems
• Interactive tools on operative municipal level