Traditionally, flood management policies have been based upon the design standard philosophy, where policy makers decide on an appropriate protection level to be achieved within the flood system which is used to design and manage hydraulic infrastructure. In contrast with this approach and following the guidelines specified in the EU Floods Directive 2007/60/EC on the assessment and management of flood risks, flood management policies based on risk rather than system performance have been developed in recent years. Flood risk management policies are based on the evaluation of the consequences generated by flooding events and the alleviation measures on the expected flood impacts over a given time period.
Risk-based analysis methods can be used in order to assess and manage hydraulic infrastructure which protects assets from flood events. A flood-risk methodology analyses a hydraulic system based on the evaluation of the consequences derived from the service of the hydraulic infrastructure rather than system performance. Thus, in contrast with traditional performance methods, in which the hydraulic system is expected to service a specific loading level, a flood risk approach should take into account all type of events based on their probability of occurrence. The results of the analysis provide a comprehensive view of the performance of the hydraulic system and the consequences derived from flood events. These results can support engineers or stakeholders in order to take informed decisions to improve the design, maintenance, rehabilitation and management programs associated with a hydraulic system and alleviate the impact of flooding.
It is important to highlight that these methods seek to provide not only a quantification of the current flood risk associated with the system, but also a long term planning framework that will help to make rational decisions related with flood-risk management and alleviation strategies. Along these lines, a risk-based option appraisal involves the modification of the variables which describe the flood system in order to estimate the consequences that the option under consideration causes on flood risk. Thus, different flood risk management options can be assessed and compared between them in order to find the most cost effective one. Given the intense nature of water infrastructure investment, strategic decisions involving long term planning and management can be based on the outcomes derived from a flood-risk analysis.
Following the principles stated above, a flood risk analysis module RiskMaster has been implemented within the modelling software platform InfoWorks ICM (Integrated Catchment Modelling). This new module takes advantage of the modelling power of InfoWorks ICM which enables users to incorporate hydraulics and hydrology into a single model and integrate urban and river catchments. The risk analysis methodology considers multiple events and based on the probability of occurrence combines together the inundation results with a database of receptors and their vulnerability to produce an estimation of the impact of floods from the economic point of view, in terms of an estimated annual damage (EAD) value. Moreover the flood risk analysis produces a database of inundation depths ordered by return period which determines the flood recurrence for each receptor.
On-line Information Resources
You can find more information and some example screenshots at http://www.innovyze.com/products/RiskMaster/. Alternatively, you can download a copy of our complete Innovyze software brochure by clicking here. This contains details of all products in our “Project Management” portfolio, with the option to download a PDF of either the entire booklet or just products like RiskMaster.
Pre-requisites for RiskMaster analysis
You’ll need a suitable 2D InfoWorks ICM model that predicts localised flooding. You’ll also need good quality GIS data of the catchment (to provide houses, urban pathways and natural embankments) and good quality DTM/DEM/BEM data, then you have everything needed for your base model. To apply RiskMaster you’ll also need access to some ‘Receptor’ information for the properties at risk and corresponding Damage Curves, which typically come from documents such as the UK’s Multi-Coloured Manual (data from the 2010 MCH_CD is ideal and can be read directly into RiskMaster, but generic data is fine in the absents of any official Damage Curves).
As complicated as RiskMaster can sometime look, at its most basic level it’s simply taking a water depth predicted by a 2D element that’s touching a building and using that depth as a look-up value on a supplied damage curve to extrapolate a financial cost associated with that depth of flooding at that property. The ‘magic’ comes in being able to do that for all Receptors (properties) in a given area in a single simulation and repeating the process for many different return periods and durations to quickly predict an overall EAD (Estimated Annual Damage) value for the catchment as a whole or specific property types in the catchment. We’ve produced a short PowerPoint Presentation which highlights the key features of the new RiskMaster software and how they are applied. You can watch the 15 presentation via the Innovyze YouTube channel (An Introduction to InfoWorks ICM Risk Master).
There are two video tutorials which you should watch to help you get started with the software.
- Using InfoWorks ICM RiskMaster Part 1 – Adapting an existing InfoWorks ICM urban 2D model. In this video we look at the process of adapting an existing InfoWorks ICM urban 2D model in preparation for analysis using the ICM RiskMaster tool. Concentrating on one particular property, the video looks at how ‘Damage Receptors’ are associated with buildings and the surrounding 2D mesh elements. The video also shows the process of importing industry standard ‘Damage Curves’ which relate water depth and flood duration to financial damage. The video explains how these damage curves are used to establish the cost of damage caused by rising water levels around, or inside, a property.
- Using InfoWorks ICM RiskMaster Part 2 – Running hydraulic and risk based simulations. This video explores the process of running hydraulic and risk based simulations within InfoWorks ICM RiskMaster. The video explores the various outputs from ICM RiskMaster and shows how the resulting Flood Damage and Financial Risks are reported by the software. It also shows how the results can be displayed within the standard InfoWorks ICM GeoPlan view or exported to either HTML or CSV output files, which is very useful if the data/results will be applied in 3rd party applications.
RiskMaster is part of the InfoWorks ICM Suite, which is the Full Edition of InfoWorks ICM (i.e. 1D & 2D) plus the Time Series Database (TSDB), the PDM Module and RiskMaster add-on packages. In years gone by RiskMaster, TSDB and PDM were sold as separate upgrades for ICM, but in 2015 a decision was taken to bundle them all together under the “ICM Suite” banner.