A Zero-Pore-Pressure Slope Infiltrometer for Controlled Saturation and Accurate Hydraulic Conductivity Measurement

Soil water infiltration fundamentally governs hydrological processes, yet existing measurement methods remain inadequate for slope conditions. This study presents a novel slope infiltrometer designed for precise infiltration measurements under saturated, zero-ponding conditions across 0°-42° slopes. The system combines Mariotte-controlled water supply with minimal soil disturbance (2 cm insertion depth), successfully characterizing silt to sandy soils (T1-T6 tests). Validation against TDR measurements demonstrated strong agreement, with absolute moisture content errors of-4.6% to +0.4% (83% of cases within ±11% relative error). Compared to conventional methods, the design eliminates surface pressure gradients while remaining insensitive to initial moisture conditions, enabling direct saturated hydraulic conductivity determination. The technique provides complete infiltration curves within 1-6 hours, offering significant advantages for hillslope hydrology studies and irrigation design under natural slope conditions. Article type: Research article Cited as:Wu MX,Song SX,Zhan ZG, 2025. A Zero-Pore-Pressure Slope Infiltrometer for Controlled Saturation and Accurate Hydraulic Conductivity Measurement, GeoStorage, 1(1), 71-79. https://doi.org/10.46690/gs.2025.01.05