OMOVAST - Operativ Model til Varsling og Styring

OMOVAST is a 2 year development and demonstration project, which focus on improved warning of heavy rain and torrential rain in the greater Copenhagen area and a prediction of the possible flood in terms of location and extent. The project was carried out with an aim to be able to act earlier and more precisely, when flooding can occur as a result of intensive rainfall. This will complement the long-term climate protection of greater Copenhagen and give direct help to the performance of the Emergency Management.

OMOVAST had the following objectives:
• Longer and more precise forecast of the rain.
• Warning of flood and estimate on the extent of the flooding.
• A tool that may be used in the simulation of future climate adaptation measures.
• Demonstrate the developed flood forecast tool on two areas.

Within the project is developed a forecasting tool that can deliver a 6-hour flood forecast, based on a forecast of precipitation generated by DMI’s forecast model for extreme weather. The Mike Urban model is kept up-to-date, with regard to the water in the drainage system and on the surface, by means of rain data from online rain gauges. The result of the calculation is then converted to a forecast animation that shows the extent and depth of the resulting flooding. This animation is published on a website which is available for the emergency response team and if the forecast shows water on the ground a sms is sent to the emergency response team.

The flood forecast Systems is set up to run automatically 24 hours a day 365 days a year. If an error occurs in the data communications and/or calculations an operator are notified automatically via a sms from the system.

The forecast tool is implemented for the two areas located in the catchments of respectively Lynetten and Spildevandscenter Avedøre Treatment Plant. The two Mike Urban models that are set up for these areas are calibrated and verified with a good result. In addition, they are optimized with regard to processing time and stability. In this report some of the results are presented. Further documentation of the model development and the model results can be provided by contacting Krüger A/S.

The forecast tool has been in test operation since the end of June 2014 and the Mike Urban models have performed highly satisfactory. There has been some errors regarding data communication to DMI and to HOFOR but overall, the system has been running well. In the test period there has not been many bigger rain events that could be used to test the functionality of the system.

There have been some difficulties with making precise precipitation forecasts during the test period. DMI has worked on these issues and there have been significant improvements and there are plans for further actions that will improve the precipitation forecasts.

There have been held workshops and information meetings for users of the system, where methods for presentation of forecasts, forecasts uncertainty and methods of warning have been discussed. Copenhagen police, the Fire Department and the emergency response team have participated in these. The Forecast tool is still running in test operation with Krüger. The Nature Agency and the Danish Ministry of the Environment has allocated grants for an OMOVAST II project which means that the decision regarding the future operation of the system has been postponed.