In mathematical modeling of groundwater flow mechanics through conduit system, generally the cross sectional area of a karst conduit is non-circular, even tend to be irregular. This irregularity causes the karst conduit difficult to be defned as euclidean geometry, but more appropriately presupposed as fractal geometry. Therefore, dealing with groundwater in karstic aquifer, some flow mechanics equations such as Bernoulli equation, need to be reviewd. This paper tries to develop some existing flow mechanics equations to make those acomodatable for fractal geometry. It is expected that the more acurate results will be acquired.Sari B. Kusumayudha, MT. Zen, Sudarto Notosiswoyo, dan Rudy Sayoga Gautama
