Applying SWE in the hydrological domain

In the hydrological domain there are several examples of SWE based applications. Below a project conducted by the Wupperverband, a German public water authority, and the open source initiative 52° North will be introduced.

The Wupperverband is responsible for the water management within the catchment area of the Wupper River in North Rhine-Westphalia in Germany. Its activities comprise for example flood protection and water level management.

Within the project three different use cases have been addressed:

access to and display of time series data for water level gauges and precipitation
alerting: real time notification in case of exceeded alarm values
video surveillance of rain detention basins

Access to and display of time series data

The first use case concerned the display of time series data (water level gauges and precipitation measurements). This data is displayed in a combined web based client application which is able to access both types of data provided through SOS instances. Thus, users are able to discover correlations between different data sets.

The different data sets can be displayed as graphs as well as tables, which can in addition be exported in formats like PDF (graphs and tables) or CSV (tables).

Application of the SOS at the Wupperverband

Alerting

Another important goal was the real time notification in case of exceeded alarm values (i.e. alarms in case of high water levels and strong rainfall events).

For realizing the filtering of measured data against user defined alert criteria, the system relies on a SAS instance. In order to define according alert conditions (e.g. precipitation higher than 30 mm/m² per hour, water level higher than 200 cm) a web based client has been developed. Within this client the user is also able to indicate if he wants to be alerted via email or SMS.

Application of the SAS at the Wupperverband

Video Surveillance

The third use case concerned the video surveillance of rain detention basins. These rain detention basins are often located in remote areas so that in case of a critical event (e.g. strong rainfall), it is not possible to rely on observations of employees that are on site. Instead, pan-tilt-zoom cameras are used that can be flexibly directed to those areas that are of interest.

For realizing the camera control, a SPS instance is used. This SPS is able to set the pan, tilt and zoom parameters.

Additionally the issue of privacy has to be mentioned. In order to avoid that other areas (e.g. private properties) are illegally observed using the camera, its field of view is automatically restricted by the SPS only to certain allowed areas.