Question

yo 2. Given the following information on three piezometers, A, B, and C, in the same horizontal unconfined aquifer (K = 10 m/day), draw groundwater contours, give the direction of flow, calculate the hydraulic gradient, and the Darcy velocity. 6*8 - A, B, and Care 1,000 meters apart from each other. - A is directly north of B. 25 30 Ground Elevation (m) Depth to Water (m)

Answer 1

000" Calculate ground-water Elevation at each point Aso illustrated below, Toomla height of ground water can be caliulated as 1000 m - -Iooom WA = 130-20 = 110 m WB = 145-25 = 120 m We = 160 - 30 = 130m sonnd water. 13om Datum As water moves from high hydraulic head (w) to low hyd head, so . Directions can be established as Shown above.

Hydraulic gmdients (° ) = 120-110 = 0.01 mm I DOD la-c) Shoe = 130-110 = 0.02 ") = 0.02 130-110 1000 = 130-120 = 0.01 mm 1000 Darry's velocity UAB = Kino = 10x 0.01 = oj mld VAL =kinc= 10x 0.02 = 0.2 mld Voc = k irc = 10x 0.0l = 0.1 mld. A(110 m) (115) (120) Contours can be plotted (125) i 17c (130) by joining points having Same ground water table elevations ije (w) walues Conturs / B (120) Z ;' (125