Delegate pack inserts for the ICE Flooding Conference 2013 - Developing Flood Resilient Communities (23 May 2013 - London, UK).

1. ©DHI
Traditional approaches to flood risk management in the UK have focussed primarily
on the physics of flood water inundation from rainfall, rivers and the sea. An
understanding of the processes involved is critical in defining the level of flood risk
and in establishing an appropriate level of defence. However, communities are
subjected to a range of additional impacts, over and above the quantity and speed
of flood waters, including for example the extent and persistence of flood waters
contaminated by foul sewerage and fine sediments.
We believe that accurate modelling of flooding risk and its wider impacts is essential
to deliver flood resilient communities. DHI was a pioneer in the development of truly
integrated water modelling software. Today, our software is unrivalled in respect of
flexibility, accuracy and performance; allowing the widest range of flooding and
environmental impacts to be considered.
The MIKE by DHI product family encapsulates more knowledge and covers a wider
range of water modelling needs than any similar products. Our software tools are
used by professionals in 140 countries across all continents, and are available in
many sizes, flavours and languages - and most recently also in the cloud. Getting
access to our global knowledge has never been easier! MIKE by DHI represents
more than 50 years of research and practical experience - right at your fingertips -
making you the expert in water environments.
MIKE FLOOD
MIKE FLOOD is the most complete toolbox for flood modelling available. It includes
a wide selection of 1D and 2D flood simulation engines, enabling you to model
virtually any flood problem. Whether it involves rivers, floodplains, floods in streets,
drainage networks, coastal areas, dam, levee and dike breaches or any
combination of these. Where other tools give up, MIKE FLOOD gives results!
MIKE FLOOD is applicable at any scale from a single parking lot to regional
models. Independent studies show that you can save months of efforts and create
more reliable models by upgrading from standard 1D modelling to MIKE FLOOD!
Typical MIKE FLOOD applications include: -
 Rapid flood assessments
 Flood hazard mapping
 Flood risk analysis for industrial, residential or cultural heritage areas
 Flood contingency planning, for example planning of evacuation routes and
priorities
 Impact assessments of climate change issues
 Flood defence failure studies
 Integrated urban drainage, river and coastal flood modelling
OVERVIEW
RELEVANT SOFTWARE
BENEFITS
State-of-the-art technology under continuous
development.
Professional documentation, training, support
and maintenance.
A range of different licenses to suit every
need.
MIKE by DHI software truly models all
sources of flooding:
MIKE BY DHI DELEGATE PACK - ICE FLOODING 2013 PHOTO: ISTOCK © ON-AIR
ENABLING RESILIENT COMMUNITIES
Application of MIKE by DHI Software to develop integrated solutions to flooding
and its wider impacts
MIKE FLOOD
Urban, riverine and coastal
flood modelling and mapping
MIKE URBAN
Modelling and GIS for water
in urban environments
MIKE 11
River modelling
MIKE 21
2D modelling of coastal and
inland waters
MIKE SHE
Integrated catchment model-
ling and groundwater
FEFLOW
Advanced groundwater
modelling
MIKE 21C
River hydraulics and mor-
phology
Flood Toolbox
ArcGIS based disaster risk
management
REAL TIME
River operations, flood
forecasting and early warning
 Fluvial
 Coastal
Incl. wave overtopping
 Estuarine
 Tsunami
 Groundwater
 Surface water
 Sewer
 Canal
 Reservoir / dam
breach
 Mining
 Flood defence
failure
For a free evaluation of our software please
contact us on the details below.

2. ©DHI
2
MIKE FLOOD features: -
1D Engines
 1D river network - based on DHI’s classic hydrodynamic
engine for rivers and open channels.
 1D sewer network – based on DHI’s equally classic engine
for sewer and drainage networks.
2D Engines
 Single Grid - the classic rectilinear model. Easy to set up
and easy input/output exchange. Now with parallel
processing.
 Multi-Cell Overland Flow Solver utilising higher resolution
DEM information on a coarser simulation grid. The
simulation speed is much faster, compared to standard
simulation with a fine resolution DEM.
 Flexible Mesh (FM) - maximum flexibility for tailoring grid
resolution within the model. The FM engine supports
parallel processing.
Structures
A range of culverts and weirs can be handled both in the 1D
and the 2D engines. In addition, operational structures can be
included in the 1D networks using add-on modules.
Fully dynamic, fully Integrated flood modelling
The 1D and 2D engines can be coupled to provide full
flexibility and the capability of investigating complex problems.
MIKE FLOOD features a fully dynamic and integrated
modelling approach for coupling of Riverine, Urban and 2D
Overland models depending on your project requirements.
URBAN FLOODING
Today's demand for accuracy often calls for using a 1D pipe
flow model combined with a 2D overland flow model. MIKE
FLOOD offers such a model combination through the coupling
of MIKE URBAN CS (Catchment Systems) and MIKE 21.
MIKE FLOOD efficiently simulates any cause of urban
flooding, including heavy local rainfall, insufficient flow
capacity of storm water inlets or the drainage network, and
flooding caused by overtopping of nearby river or coastal flood
defences.
Urban flooding in MIKE FLOOD is simulated through model
couplings at the location of nodes, pumps, weirs or outlets.
Water is exchanged between the pipe flow model and the
overland flow model through these couplings in a dynamic two
-way process.
Defining the couplings between pipe and overland flow model
as well as launching simulations and visualising results are
supported in the GUI of both MIKE FLOOD and MIKE
URBAN.
RIVERINE FLOODING
MIKE FLOOD is an efficient and flexible tool for river flood
modelling when investigating flood hazards and flood risk from
rising water levels in the river/canal system and/or from high
rainfall intensity in the catchment area.
Flooding can be investigated on multiple scales ranging from
large scale basin areas to local impacts in specific low lying
flood prone areas along the river.
When simulating river flooding, the combination of a 1D open
channel model using MIKE 11 and a 2D overland flow model
using MIKE 21 is typically preferred.
The flexibility of the combined 1D-2D engines provides
numerous opportunities for analysing complex issues such as:
 river conveyance problems due to improper maintenance
of the vegetation
 limited flood storage capacity
 infrastructures crossing the river/floodplain
 operation of hydraulic structures and reservoirs
 dam breaks or levee breaches
 changes in land use
MIKE 11 and MIKE 21 can be coupled either at specific points
or distributed along entire river stretches on either side of the
main river channel.
COASTAL FLOODING
MIKE FLOOD is ideal for efficient and accurate assessment of
coastal flood risks, whether they are related to flooding of
coastal cities and infrastructures, or to inundation of
reclaimed or low lying areas.
The flexibility of MIKE FLOOD components enables
professional modelling of complex and dynamic events due to
ocean storm surges, and the impacts in estuaries, rivers
and drainage canals as well as sewer systems.
MIKE FLOOD offers the possibility to investigate the effects of
coastal protection, such as dikes/polders and tidal gates or
other operational structures in delta areas.
Combined with one of the MIKE wave models (MIKE 21
Spectral Wave or MIKE 21 Boussinesq Wave). MIKE FLOOD
can address all aspects of coastal impacts of storm surge and
inundation (see page 3).
MIKE BY DHI DELEGATE PACK - ICE FLOODING 2013
DYNAMIC FLOOD HAZARD MAPPING
Depending upon the approach adopted
(e.g. the ‘Flood Risks to People’ guidance
from Defra / EA) MIKE FLOOD can utilise
the floodwater depths, velocities, and
land use data to seamlessly calculate
both the debris factor and appropriate
flood hazard rating in each grid cell /
element and at each time step in a
simulation.
USE OF MIKE FLOOD FOR BREACH ASSESSMENTS
MIKE FLOOD includes numerous options for the rapid, dynamic
assessment of breach failures in river and coastal flood defences,
canal embankments and dams (Reservoir Inundation Mapping): -
 Coupled MIKE 11 Dambreak structures
 MIKE FLOOD side structures links
 MIKE FLOOD time varying lateral links
 MIKE 21 time varying bathymetry - Landslide option
 MIKE 21 FM time varying bathymetry - Dynamic bathymetry
 MIKE 21 FM Dike structures

3. ©DHI
3
EXTENDING THE CAPABILITIES OF MIKE FLOOD
For more than a decade, MIKE FLOOD has offered complex
and flexible features for coupling 1D and 2D hydrodynamic
models. Flood extents and flood hazards have been some of
the key issues for flood risk management. These issues will
still be the focus for many modelling applications in the future
however, in order to support wider EU Water Framework
Directive objectives, there will be a need for more detailed
studies; particularly water quality assessments.
MIKE FLOOD now offers the option to simulate the transport
and spreading of pollutants during a flood event through a fully
dynamic coupling of the Advection Dispersion modules of
MIKE 11, MIKE 21, and MIKE URBAN.
In addition to water quality, increased focus on whole
catchment approaches including transitional waters will
require consideration of the interaction at the coast. As such,
MIKE FLOOD is being used to undertake detailed flood impact
assessments where overtopping is a particular concern.
MIKE BY DHI DELEGATE PACK - ICE FLOODING 2013
EXAMPLE PROCEDURE FOR CALCULATING FLOODING
DUE TO OVERTOPPING OF DEFENCES BY WAVE ACTION
The standard approach to calculating wave
overtopping volumes is through the use of
EurOtop, the European Overtopping Manual,
which offers a number of methods to calculate
wave overtopping at a range of different
coastal structures. Common to each method is
the requirement for wave climate at the toe of
the structure, and it is this that is the most
significant challenge in the correct usage of
EurOtop.
The following example methodology is presented for inspiration
only.
STEP-BY-STEP METHOD
1. Assess Offshore wave conditions
Wave conditions from the Met Office wave model are
generally considered to be ‘offshore’ as they tend to be in
relatively deep water. These can be applied as boundary
conditions to an offshore wave transformation model.
2. Offshore wave transformation modelling
The MIKE 21 Spectral Wave (SW) model simulates wave
growth due to wind action, transformation due to refraction
and shoaling resulting from depth variations, and decay due
to whitecapping, bottom friction and wave breaking. The
effects of wave-current interaction, non-linear wave-wave
interaction, diffraction and areas which dry out are also
included.
MIKE 21 SW is applied on a flexible mesh so offshore areas
can be defined with a relatively coarse resolution while
inshore areas are resolved on a finer mesh thereby
optimising runtimes and accuracy.
3. Assess Nearshore wave conditions
For an exposed simple coastline, it is tempting to use the
output from MIKE 21 SW directly in EurOtop. However,
unless the defence structure has been included in the model
at a high resolution, wave heights extracted from the model
output at the coastline are unlikely to accurately represent the
wave climate at the toe of the structure. Similarly, for more
complex coastlines where reflection is an important process,
or for wave action within harbours, outputs from SW alone
are unlikely to be suitable for use in EurOtop.
Nearshore wave conditions (generally just offshore of the
breaker zone) can be extracted from the MIKE 21 SW
outputs and used as boundary conditions for a MIKE 21
Boussinesq Wave (BW) model which is a phase-resolving
model that solves the shallow water equations for waves in
nearshore areas using the Boussinesq approximation.
4. Nearshore wave transformation
MIKE 21 BW can be used in either 1D or 2D forms. If the
coastline where the defence structures are located is
relatively straight and of uniform cross section, a 1D
approach can be used to transform the nearshore waves
along a profile normal to the defence structure. By including
the defence structure geometry in the BW model bathymetry,
the wave climate at the toe of the structure can be directly
extracted from the 1D BW model results.
For more complex coastlines or harbour sites, a 2D approach
may be required. Again, inclusion of the defence structures in
the model bathymetry will ensure that the wave climate at the
toe of the structure can be extracted directly from the model
results, at any site along the defences where overtopping
calculations are required.
5. Overtopping calculation
Having determined the wave climate at the toe of the defence
structures, calculation of overtopping volumes using EurOtop
can be undertaken. Resultant volumes can then be routed
overland behind the defences using MIKE 21 or MIKE
FLOOD.
USING MIKE FLOOD AD & ECO LAB TO MODEL POLLUTED
FLOOD WATERS AND RIVERINE WATER QUALITY
MIKE FLOOD now includes the option for a fully dynamic 1D-2D
Advection Dispersion coupling, which increases the range of
applications substantially.
The new AD coupling in MIKE FLOOD enables users to simulate
new interesting aspects such as: -
 Floodplain contamination from polluted rivers.
 Impact assessment on river quality from pollutant sources in
flood prone areas during flood events.
 The impact on concentrations of river pollutant in case of a
release from an urban Combined Sewer Overflow.
MIKE FLOOD AD can be further enhanced by ECO Lab for
advanced water quality simulations.
ECO Lab is the complete numerical laboratory for water
quality and ecological modelling. You can develop exactly the
model you need and describe the processes you wish. No
ecological problem is too simple or too complicated for ECO Lab:
 Open Equation solver for coupled ordinary differential
equations.
 Designed for point descriptions of processes of chemistry,
ecology, etc.
 All equations, parameters contained in flexible, portable ECO
Lab templates (use DHI supported templates or create your
own).
 Integrated with DHI’s hydrodynamic models: Currently MIKE
11, MIKE 21 (hence MIKE FLOOD), MIKE 3 & MIKE SHE.
Photo:iStock©MikeBentley

4. ©DHI
4
GROUNDWATER FLOODING
MIKE SHE delivers truly integrated modelling of groundwater,
surface water, recharge and evapotranspiration - all important
aspects of hydrology when your project requires a fully
integrated model. No other tool or combination of tools can
match MIKE SHE in terms of seamless integration of all the
important processes of the hydrological cycle.
MIKE SHE includes 2D overland flow capabilities and full
riverine hydrodynamics (with MIKE 11) delivering a powerful
1D-2D flood modelling tool when evapotranspiration,
infiltration and groundwater are relevant.
For detailed groundwater-surface water interaction studies
(including water quality), MIKE SHE includes 3D, finite
difference groundwater flow, which discharges groundwater
drainage directly to surface water.
An unrivalled dynamic coupling of MIKE SHE with MIKE
URBAN is also available allowing the accurate modelling of
the two-way interaction between pipes in the ground and the
surrounding aquifer. This facilitates the modelling of infiltration
to and leakage from pipes as well as modelling of the potential
side effects of infiltration prevention.
MORPHOLOGY
The primary long term factors affecting river hydrodynamics,
and flood risk, are climate change and urbanisation. However,
the consideration of other factors may also be critical.
Morphological change, for example, is too often limited to the
consideration of scour or silting at structures, and to the
development of river maintenance schemes.
For broad scale sediment transport studies, MIKE 11 may be
sufficient. However, to inform the detailed design of flood
defences or other structures, bank stability assessments, and
to assess the effectiveness and impact of erosion control
measures (hard or soft engineered) on river health and future
habitats (e.g. fish spawning grounds) the MIKE 21 Flexible
Mesh series is preferred. More advanced morphological
modelling - including planform change - is possible using
MIKE 21C (Curvilinear Grid).
The transition from 1D to 2D modelling is streamlined by the
automatic generation of 2D bathymetries from MIKE 11.
MIKE BY DHI DELEGATE PACK - ICE FLOODING 2013
DHI Water Environments (UK) Ltd
Davidson House
Forbury Square
Reading, RG1 3EU
United Kingdom
+44 (0)1189 000745 Telephone
mikebydhi.uk@dhigroup.com
www.mikebydhi.com
ABOUT DHI
DHI are the first people you should call when you have a tough challenge to solve in a water
environment. Whether it is a river, a reservoir, an ocean, a coastline, within a city or a factory. Our
world is water, and our knowledge of water environments is second-to-none. It represents 50 years
of dedicated research, and real-life experience from more than 140 countries.
We strive to make this knowledge globally accessible to clients and partners by channelling it
through our local teams and unique software.
So whether you need to save water, share it fairly, improve its quality, quantify its impact or manage
its flow, we can help. Our knowledge, combined with our team’s expertise and the power of our
technology, hold the key to unlocking the right solution.
MINING & MINE WATER MANAGEMENT: A FOCUS ON
FEFLOW
Mine flooding can not only alter
underground hydrogeology, but
also cause the collapse of mine
workings (potentially exacerbating
groundwater related flooding
elsewhere), ground subsidence
and damage to surface structures
both in the mine and in the
surrounding area. FEFLOW can
be used to predict the locations
and severity of flooding within a
mine and to model the long term
performance of flooding control measures, as well as optimise
dewatering works (emergency or long term), in operational and
abandoned mine workings. FEFLOW can also be used to
develop effective early warning systems, to validate remediation
schemes for groundwater contaminated by mining activity, and to
assess the risk of uncontrolled discharge to surface waters of
pollutants mobilised by rising flood waters within the mine.
FEFLOW is our state-of-the-art integrated groundwater software
package for the modelling of fluid flow, transport of dissolved
constituents and heat transport processes in the subsurface.
FEFLOW links with MIKE 11 for groundwater - surface water
interaction problems (river flow).
CLIMATE CHANGE ADAPTATION
DHI has developed a set of Climate
Change Guidelines. For your free copy
please visit climatechange.dhigroup.com
ASSESSING THE IMPACTS OF RURAL LAND MANAGEMENT
CHANGE ON FLOODING AND FLOOD RISK (THE
CATCHMENT APPROACH)
MIKE SHE is a very powerful tool for
assessing the effects of natural flood
management schemes in the UK. The
software has been used extensively for
modelling wetland restoration in upland areas
in different parts of the world.
The effects of tree planting, water meadows, and other riparian
planting can be described by land use changes in the model and
the impacts on evapotranspiration, unsaturated flow and surface
runoff examined. It is also possible to describe the detention of
water in the floodplain (e.g. as a result of tree planting,
landscaping, etc).
The effects of cutting off drains, and altering surface flow routes,
can be modelled using the MIKE SHE 2D Overland Flow module.
Channel restoration and green bank protection can be handled
by coupling to MIKE 11.
Natural flood management has many benefits (habitat creation,
nature conservation, diffuse pollution mitigation, etc) and is of
particular interest in rural rapid response catchments; where it is
not always possible to provide flood defences.
Photo:iStock©ВасилийТороус