River management

Many rivers in Europe are overflowing their banks with alarming frequency. Flooding such as this can have disastrous consequences. The rivers Meuse and Rhine in the Netherlands, for example, as well as rivers in Germany and France, flood frequently, with a corresponding loss to economic infrastructure and impact on human activity. At the heart of the problem lies the fact that due to encroaching urban development, inadequate mapping and poor planning practices, many European rivers do not allow for adequate flood plain exclusion zones. Basically, they do not have as much space as they need to accommodate cyclical flooding. This is not only a problem with historical structures or towns. Even today there are houses, and even complete villages, being built in the flood plains of rivers that routinely overflow their banks. Extensive logging of forests throughout the watersheds further exacerbates the situation.

Fortunately, the responsible public authorities in Europe have taken notice of the problem. Recently they have started implementing a modernising approach to educate the public and to try to "give the rivers their flood plains back". They are also investing significant effort to improve their flood prediction models. Research is being conducted to estimate the impact of various interventions on the predicted and actual water levels. In situ monitoring to better predict water levels and provide accurate flood warnings is becoming more important. For this research, and the routine monitoring of the rivers, accurate hydraulic models are being developed and refined that can help calculate and predict the water levels in the river. These hydraulic models use a variety of different input data, such as the location of dikes and ponds, the borders of the main river channels and tributaries and high accuracy, high resolution elevation data of the surrounding flood plain.

TerraImaging provides a variety of European agencies with the necessary base layers and digital terrain models to allow accurate flood plain modelling and prediction to be accomplished. In a process referred to as river schematisation, TerraImaging uses its extensive in-house tools, knowledge and experience to merge all the disparate data sets in such a way that the data can easily be used as input in the various agencies' hydraulic models. Another immediate application of high resolution elevation data in river management is flood risk analysis. For example, the modelling of the flooding of areas behind a dike after a nearby dam burst is easily accomplished once a high accuracy DTM is available.

TerraImaging collects the elevation data for these flood risk analyses and river management programs exclusively with airborne laser scanning (Lidar). With high resolution, high accuracy data capture available from such sensors, combined with TerraImaging's knowledge and experience, the challenge of getting a handle on Europe's river flooding problem is being addressed.

Together with RIZA (Institute for Inland Water Management and Waste Water Treatment) TerraImaging has developed a procedure to generate SOBEK-profiles from geographical databases. TerraImaging contributed extensively to the development of BASELINE; an application for the storage and analysis of river system relevant data applicable to SOBEK and WAQUA. TerraImaging also contributed to the creation of SOBEK-schematisations of several large rivers like the Meuse and the Rhine in the Netherlands, but also the Neckar, Main and Rhine in Germany. This was done together with RIZA, NCR (Dutch centre for river science) and the BfG (die Deutsche Bundesanstalt für Gewässerkunde). TerraImaging specialists contributed to several planning scenarios for the river Meuse and continue to do so by supporting the project bureau "De Maaswerken".