Earthen Dam
Safety and
Reservoir Stability

Dam failures pose a serious threat to people and property. Water infiltration through the vadose zone may happen in earthen dams. It may weaken its stability and potentially lead to dam breach. Similarly, infiltration towards the groundwater may be critical, in cases where one wants to minimize or to increase groundwater enrichment. Today, most monitoring programs are based on measurement of phreatic water level by using piezometers, which actually detect free water surface in designated wells, but gives no information about the complex, unstable process that is taking place in this zone. The result is a lack of realtime, accurate data that can provide early warning of potential dam safety issues. As such, an in-situ monitoring system which measures continuously the actual conditions of the sediment in the subsurface (“dams body”) could contribute dramatically to monitor any inception of seepage, piping (in a dam) or infiltration towards groundwater.

Implementation of Sensoil’s Vadose-Zone Monitoring System (VMS) provides a real-time monitoring tool for controlling safety of embankment dams, reservoirs and aquifer recharging. It offers the ability to monitor deep sections of unsaturated sediments, such as prevail in dams and dikes. VMS is key to early detection and prevention of potential damage and loss of lives.

The VMS continuously measures the actual conditions of the sediment in the subsurface (“dam’s body”). These data can contribute dramatically to the monitoring for any inception of seepage, piping (in a dam) or infiltration towards groundwater and a crucial factor for early warning systems (EWS).

Sensoil’s patented VMS technology includes uniquely designed water content sensors, installed across the desired cross section. These sensors can detect any change in the soil moisture, temperature and water pressure (if the zone becomes saturated). Moisture sampling is also possible for water analysis. Data obtained by the VMS provides early warning on wetting processes, and contaminant flow. The VMS data is easily accessible online for real time analysis. Implementation of VMS can lead to substantial savings in maintenance and repair costs, dramatically increase construction trustability, and elevate the confidence of surrounding communities, investors and stakeholders.

Floodwater infiltration is an additional field of application. VMS installed under the streambed of a river facilitates continuous monitoring of water infiltration and groundwater recharge during flood events.