Simplified Seepage Rate Estimation of Zoned Embankment Dams

Seepage rate is a crucial parameter in embankment dam safety management, informing early warning systems and risk-based decision-making. However, under- or over-estimating seepage quantity during design-stage, often due to simplified 2D modeling, leads to discrepancies between predicted and measured values. This study proposes a modified method for estimating seepage rates in zoned embankment dams, improving upon Yang et al. (2022). A closed-form solution is also newly derived by addressing the limitation of previous study. The approach enables realistic prediction of partitioned seepage rates within the core layer and separately accounts for seepage contributions from the foundation and abutments. The accuracy of the method was verified through comparison with extensive measured seepage data from a well-monitored central cored rockfill dam. The close agreement between estimated and observed values supports the applicability of this modified method for establishing reliable seepage management criteria in embankment dams. The findings highlight that seepage through the foundation typically surpasses that through the core, attributable to differences in permeability characteristics. The ability to predict seepage quantities through different dam components individually lays the groundwork for improved seepage monitoring plans and enhanced dam safety management.