Urban stormwater is one of the biggest problems facing our waterways today. Urban cloudbursts and the resulting rapid stormwater that overflows along surfaces and in networks are more and more common in cities due to increasing impervious surface areas, climate change, aging infrastructure, and often undersized, centralized stormwater networks. Contaminants such as metals, pathogens, and pesticides are common in a runoff. VTT has developed the first concept and related research prototype of a local early warning and simulation system for urban floods caused by heavy rains in order to better manage stormwater problems.
Who needs better tools to manage urban stormwater and alerts for cloudbursts?
Cities, the property sector, rescue authorities, service providers, the security sector, and governmental authorities need heavy rain and flood predictions in order to minimize the damage to property and business and inform the relevant actors and authorities. Local early predictability of flooding gives time to react. Urban planners can apply detailed surface and underground 3D flow simulations with different cloudburst or climate change scenarios when designing effective solutions to manage stormwater quantities and qualities.
Development of smart alarms for urban flooding
A unique 3D flood forecast simulator has been developed that can link and be continuously calibrated by live data sources (from short-term weather predictions into wireless sensor networks) with a wide range of dynamically integrated models (surface, stormwater, and sewer network, water quality, underground and building space models) to provide detailed, accurate forecasts of water levels, flood depths, flows, velocities and water quality parameters also in real-time. Other integrated methods include LIDAR scanning (accurate street-level 3D models of urban areas), measurements (weather radar, rain gauge sensors, water levels, network flows, surveillance cameras, etc.) and modern ICT technologies, such as web services and other IP-based data communication, GPS, Google Maps, and IOS-based tablet and smartphone technologies. The test site for the system was the center of Helsinki, the capital of Finland, with many flood-prone properties both above and below ground. The risks are evaluated from the property owners’ point of view and each critical threshold is evaluated individually. The prototype raises alerts by reporting targeted information on flood events to key building security personnel, rescue services, local control room operators, etc. The system reports exact locations in the target area that are or will be, in a critical situation now or in the coming minutes or hours (10 min, 30 min, 1 hour, 2 hours, etc.). The system also gives other flood-related information, such as emergency procedure recommendations.
New business opportunities also from the insurance sector
More than 3 billion people have been affected, with major flood events causing the death of almost 7 million people and causing damage of about 441 billion USD over the last century. This has meant huge insurance compensation. The insurance industry is currently developing flood protection policies and insurance products, but there are no tools to evaluate the building-level flood risks, which is a very data-intensive and challenging task. Thus, it is difficult to establish accurate prices for property insurance. Large companies in the property sector are also interested in flood risks relating to their buildings.