Penetrometer-Based Installation of Fiber Optic Sensors for Optimized Levee Intervention Design

Accurate prediction and observation of seepage behavior in river levees are essential for the design of effective and sustainable mitigation measures. This study presents an integrated monitoring and modeling framework applied to a levee in north-eastern Italy experiencing recurrent seepage events. Distributed Temperature Sensing (DTS) and pressure transducers were deployed to capture hydraulic and thermal responses over multiple seasons. A central innovation of this work is the development and implementation of a novel sacrificial tip for Penetrometer-Based installation of DTS cables. This tip minimizes soil disturbance, ensures precise sensor placement, and enables rapid installation of multiple vertical profiles using a single continuous cable. A thermo-hydraulic numerical model was used as a supporting tool to interpret the thermal signature of seepage under varying soil permeability conditions, confirming the dominant role of permeability in controlling advective heat transport. The combination of depth-resolved temperature measurements enabled by the proposed installation technique and supporting numerical analyses provided clear information on the depth and spatial extent of seepage pathways, directly supporting the definition of proportionate remedial interventions. Post-intervention monitoring confirmed the effectiveness of the adopted solution, highlighting the reliability of Penetrometer-Based DTS installation as an enabling approach for intervention-oriented levee monitoring.