Fluctuations in groundwater levels are a determining factor for the sustainability of habitats. Therefore the Research Institute for Nature and Forest (INBO) has set up the WATINA network, a monitoring network of over 9000 groundwater wells in Natura 2000 areas in Flanders. However, this assignment is hampered by factors such as accessibility of the terrain and manpower. The INBO already experimented with devices that monitor the groundwater levels and log them in an internal memory, but hardware failures or external factors such as vandalism can result in loss of months of data.
Therefore, in the framework of LifeWatch, the INBO is now extending its monitoring techniques by using devices that can expose the groundwater levels real-time without the need for any manual intervention and thereby reducing the risk of data loss when severe issues occur. The devices use an internal modem and a SIM card to send the data over the mobile network and they are employed in terrains with specific issues such as military domains or floodplains.
In 2014, 15 groundwater loggers equipped with a GPRS modem were deployed in the field: five in the military domains of Houthalen-Helchteren and five in the military domain of Beverlo, in the valley of the Zwarte Beek. The other five were deployed in floodplains in Webbekoms broek, Schullens break and the Dijle Valley (see map below).
Left: Location of the 15 deployed groundwater loggers with GPRS functionality. Loggers deployed on military domains are indicated in orange, loggers deployed on areas that may be flooded in purple (©INBO) - Right: Groundwater well in the WATINA monitoring network (©INBO)
During the first half of 2015, the INBO has been working on a Extract, Transform and Load (ETL) procedure that retrieves the data from the loggers and stores these in the internal WATINA database. There, INBO researchers can use an internal procedure to calibrate the measurements based on available control measurements. These procedures are now fully operational andnew measurements are received on a daily basis.
The next and final step, which will be tackled in 2016, is to develop a web service that allows external researchers to retrieve the data in an automated way. Both uncalibrated and calibrated measurements will be exposed, since calibration is a manually triggered process which requires time and we see relevant use cases for both types of data.