Flood Modelling of Boulder Creek for Emergency Response Planning Using MIKE 21

Purpose of Modelling

Predicting inundated areas and response time is critical for planning emergency response in the case of flash flooding.  To this end, the Urban Drainage and Flood Control District, in conjunction with the City of Boulder and DHI Water & Environment prepared a 2-dimensional (2D) model of overland flooding in the Boulder Creek drainage basin using the MIKE 21 modelling software developed by DHI Water & Environment.  A 2D model was chosen for the ease of development and results presentation capabilities.  “A 2D model can be developed rapidly and with much less effort than a 1D model, given that appropriate topographic data is available.” said Chad Kudym from UDFCD.

The objective of the modelling was to provide Urban Drainage and Flood Control District (UDFCD) with static inundation maps, travel times for the flood wave propagation and flood animations for Boulder Creek, based on MIKE 21 model results.  The inundation maps and flood animations were used for illustrative purposes during an emergency preparedness exercise in Boulder, CO.

Approach

The project consisted of two main tasks, hydraulic modelling and result presentation.

The model bathymetry was developed from existing USGS 10m DEM data while the model extents were developed based on delineation of the area of interest provided by UDFCD.  The model domain extends from approximately half a mile upstream of Orodell to Canyon Park.  This represents a stream channel length of approximately 10 miles.  The model extents are shown in Figure 1 below.  Six inflow locations and corresponding dynamic flood hydrographs were used.  The flood flow hydrographs, and inflow locations were specified and provided by UDFCD.

Figure 1: Flood Model Extents

Based on the hydraulic modelling result files, flood hazard maps were prepared delineating the maximum flood depths based on the simulation results, and 2D animations of the flood inundation were prepared.  These maps and animations were used to aid in developing and testing an emergency response plan.

Figure 2: Sample Flood Hazard Map

“The animations and prepared mapping were extremely useful in understanding the areas at risk to flood and the travel time of the front of the flood” said Chad Kudym.  

Results

Mr. Kudym continues “Flood modelling for emergency response planning is quite different than flood mapping for insurance purposes.  The main modelling goals for emergency response planning are a reasonable estimate of inundation areas and response times, while keeping the model development costs to a minimum.  Using a 2D model precluded the need to spend a lot of man-hours developing model geometry, and defining flow paths and flow splits.  All of these were taken directly from the specified topography.  By using a tool like MIKE 21 we were able to quickly develop representative flood models for emergency response planning at low cost.”

For further information please contact Eric J. Fontenot at ejf@dhigroup.com

Microsoft TechFest 2006

DHI was invited to present our technology and especially our plans and developments for the windows platform VISTA.

The TechFest was held for the first time in Denmark and was an opportunity to see what other companies are doing and get to liaise with the Microsoft Development Centre and Microsoft Research.

Alongside the TechFest Steve Ballmer launched VISTA which is now ready to be shipped. DHI intends to leverage the new possibilities on the VISTA platform. For instance you will be able to search your file

system also on file content - which means that instead of having to remember what you named your dfs2 file or when you created it  - you can search for a geographical location, embedded items, simulation period, etc. Some strong graphical opportunities are made available with VISTA to navigate with multiple open windows and get intelligent previews of data files and model setups. For DHI Software the fact that VISTA is truly 64bit and more strongly supports muliticore CPUs opens up new possibilities for how we model water.

For further information please contact Peter S. Rasch at ptr@dhigroup.com

A new approach to dam break modelling

A dam break study has been carried out in collaboration with the Spanish University of Alicante using the MIKE 21 HD mudslide module. Thereby describing the dam breach by using the bathymetry. The study was carried out for a real estate developer who in order to get the necessary building permits had to prepare a flood study of the area.

The effect of the dam break is modelled by forcing terms representing the dynamic vertical deformation of the bathymetry plus additional terms to represent the effect of the dam break due to viscous and inertia forces.

A full description of the approach and modelling technique may be found here

For further information please contact Peter Torp Larsen at ptl@dhigroup.com

Temporal Analyst

Temporal Analyst (TA) contains many tools for analyzing, correcting, combining and manipulating time series records. A great number of specific tools are available for the most common analyses. But from time to time users have specific needs for their specific applications.

For example, TA includes one specific tool for disaggregating monthly records into daily records. However, TA does not include a similar tool for disaggregating e.g. daily records into hourly records. Fortunately, TA has a number of “generic” tools available that in combination can represent the tool you need.

In the following simple example we disaggregate a daily record into an hourly record. For this you require two time series, the first is the Master hourly time series and the second is the Daily time series you want to disaggregate to follow the hourly pattern of the hourly master time series. After both time series have been added to the Time Series Analysis Frame, the following three steps are required:

1. Use the Resample tool to resample the hourly time series into an average daily time series;
2. Move the resampled time series from the TSAnalysis Output tab to the TSAnalysis Input tab, and
3. Use the Calculator to calculate the new disaggregated time series using the following equation:  < Master hourly  TS> / <resampled hourly master TS> * <Daily P TS> .

The result will be a new hourly time series that is follows the variation of the Master hourly time series and on a daily basis equals the original daily time series.  The green curve below shows the new hourly time series based on the daily time series (the blue curve).

MIKE URBAN: Insert XY Value Layer

If you need to display data, which is stored in text files or database files without the corresponding graphical representation (i.e. there is no GIS or CAD layer for it, for example) you can use "Edit | Insert XY Value Layer" feature. MIKE URBAN will read the text file, will recognise X,Y values from the first data row heading and the graphical layer (points) will automatically be generated in the Table of Contents and displayed on the Map.

This is suitable for quick display of various data file with X,Y information such as list of monitoring points, X,Y,Z elevation files, water consumption files, and other data generated from spreadsheets or database systems without corresponding GIS layer.

Coffs Harbour City Council selects DHI's MIKE URBAN, a Single Modelling Platform for Sewer and Water Supply Networks

DHI’s local presence and established track record of providing our clients with efficient software support and training was one of the key factors resulting in Coffs Harbour City Council purchasing DHI’s MIKE URBAN modelling software for both wastewater and water supply.

During the selection process Coffs Harbour City Council established a comprehensive set of evaluation criterion that included:

• User friendly interface that is easy to use and common to both water and sewer networks
• Integration with asset management data such as CCTV and other condition assessment data
• Integration of the modelling software with external databases
• Seamless operation of additional water quality modules and user tools
• Reliability of software support
• Flexible training course tailored to the clients requirements
• Commitment to future development
• The ability for integration with other software products for whole of water cycle analysis
• Competitive pricing

Coffs Harbour is one of Australia’s most dynamic cities recently being awarded the international Nations in Bloom Award for being the "most liveable city in the world" (in 2002, for cities with a population up to 75,000). Council is committed to seeing Coffs Harbour retain its unique character and special attributes that make this city such a desirable location to live and work. DHI sees the adoption of MIKE URBAN as Council’s preferred network modelling tool as an important factor in Council’s strategies to achieve this goal.

Belo Horizonte, Brazil selects MIKE URBAN

Belo Horizonte, 3rd largest city in Brazil and the capital of Minas Gerais State with the population of app. 4.5 million inhabitants selects MIKE URBAN software for water distribution modelling. The development of both off-line and on-line strategic model of the water distribution system will be finished in 2007 and will be followed by the development of a detailed water distribution model.

Belo Horizonte, Brazil

The GIS and SCADA integration is done jointly with Telvent (http://www.telvent.com), the exclusive provider of SCADA technology for COPASA (Companhia de Saneamento de Minas Gerais, http://www.copasa.com.br). COPASA is operating this large water supply and water distribution system covering app. 31 municipalities, 6,000km2, water consumption of 12m3/sec and with more than 80 storage tanks, 40 pumping stations and 550 control valves.

This work is a part of the ambitious Project 3T plan of COPASA for linking 3 major technologies i.e. GIS, SCADA, and MODEL. We are pleased to work on this project together with them.

For more information contact: Poul Kronborg pok@dhigroup.com, Alejandro Lasarte ael@dhigroup.com or Petr Ingeduld p.ingeduld@dhigroup.com

Upcoming Events

DHI Software Conferences

Paris, France 2007

1st French DHI Software Conference, 6th and 7th February in Paris, France. Details are available here:

http://www.dhigroup.com/Events/1stFrenchDHISoftwareUserConference.aspx (English)

http://www.dhi.fr/Logiciels/conference2007/ (French)

Auckland, New Zealand2008

5th Asia-Pacific DHI Software Conference, March 2008 in Auckland, New Zealand. Details to be announced

Oslo, Norway

DHI User group meting and seminar

DHI celebrates the first five years in Norway with a MIKE URBAN user group and seminar on modelling of water in the city. The twoday event will take place at the Clarion Oslo Airport Gardemoen Hotel on February 13th and February 14th 2007.

A full programme (in Norwegian) is available here

Recent Events

The 4th Asia-Pacific DHI Software Conference.

About one hundred and forty participators including people from many Provinces of Mainland of China, Malaysia, India, New Zealand, Australia, Denmark, Italy, Korea, Japan, Thailand, and Taiwan joined the conference. Representatives from the six main basin areas in China also attended. Four main sessions were held at the venue hotel covering inland water, urban water, marine and estuary as well as flood management.

The conference had generated 72 papers and 64 of those were presented at the conference. The topics covered the three-gorge reservoir project, water diversion project in the Yellow River basin, Songhua River flooding management project, and nature gas terminal project at Rudong harbour (Jiangsu Province), etc.

All the papers, both in Chinese and English, are available on the conference website.

Papers are available here

“DHI Day”, Milan (Palazzo delle Stelline), Italy, 12 October, 2006

More than 100 participants from the Italian water sector including representatives from governmental agencies, regional and local water bodies, research institutions and universities, professional bodies and engineering companies, urban water utilities attended the “DHI Day” in Milan on October 12. The Intecno-DHI office in Turin was the organiser. The “DHI day” aimed at presenting an all-round and comprehensible overview of DHI expertise and experiences in the water sector. The focus was on key research developments and policies of DHI Water & Environment; Decision Support Systems and Real Time Control; water leakage management; water forecasting in coastal areas; aquaculture & virtual world; health and environment.

DHI DK participants were: DHI Managing Director Asger Kej; Karsten Havnoe, DHI Director for Business Development and President of the Board of Intecno-DHI; Sten Lindberg, Head of Department for Urban Water Utilities; Karl Iver Dahl-Madsen, Head of Department, Ecology & Environment and Torben Madsen, Head of Department, Environmental Risk Assessment

Said at the Conference:

“This Conference has been extremely informative and useful. We discovered many different activities that DHI is covering within our sector.  It is a very easy and efficient way of keeping ourselves updated about the new developments of the DHI”.

For further information please contact Birnur Yavuz at Tel. + 39 011 56 24 649 or email: intecno-dhi@intecno-dhi.it