Minimum height of the trapezoidal filter in earth dams using Complex Function Theory

Height of the trapezoidal filter in earth dam based on an impervious base is established using Complex Function Theory.Based on different earth dam and filter dimensions, such as retained water head upstream the dam, angle of inclination and upstream face length of the filter, a new formula is derived to calculate minimum height of the trapezoidal filter.Phreatic surface through earth dam is drawn for different dam and filter dimensions. Also, seepage discharge passing through the dam per unit length is determined.Comparison between present work and both Hathoot and Kozeny is made.