Innovative real-time sensing of flow dynamics in groundwater to map the effectiveness of landscap wetting, level-controlled drainage and weirs
Groundwater dynamics play a crucial role in landscape rehydratation. However, there is still a big gap in the understanding of the groundwater flow dynamics. Heterogeneities and dynamics are often underestimated and therefore not taken into account. They are of crucial input for successful management and design of measures like weirs and level-controled drainage systems. The bulk of the mass of mass often is transported through only a small layer or section within the aquifer and is in cases of seepage into surface water very dependent to rainfall, evapotranspiration and occurring tidal effects. This study contains the use of novel real-time iFLUX sensors to map the groundwater flow dynamics over time.
The iFLUX sensor provides real-time data on groundwater flow rate and flow direction. It consists of multiple bidirectional flow sensors that are superimposed. The sensor probe can be installed directly in the subsoil, riverbed or monitoring well. The measurement setup is unique as it can perform measurements every second, ideal to map rapid changing flow conditions. The measurement range is between 0,5 and 500 cm per day.
The City Walls of Damme are a nature reserve of 140 hectares, located near walls of Dam-me. Specific measures were taken to achieve the rewetting of grasslands and swamp forests. A unique real-time hydrological measurement network supports the measures. The network consists of several iFLUX flow sensors to map infiltration, drainage & horizontal flow, combined with a network of groundwater and surface water level, salinity and meteo data. The project also includes a dune ridge infiltration to create an inland freshwater reserve in the coast and raise the freshwater table in order to counter the salinization of the coastal zone. The iFLUX sensing network is being expanded in that zone. Flux sensors in combination with EC sensors will continuously monitor the infiltrated freshwater bubble and its surroundings.