Steady flow in a confined aquifer If the distance and the observed piezometric surface drop between two adjacent wells are 1000 m and 3 m respectively, find an estimate of the time it takes for a molecule of water to move from one well to the other. K is 3.5 m/day and effective porosity is 0.35 h x From Mays, 2011, Ground and Surface Water Hydrology

Steady flow in an unconfined aquifer A stratum of clean sand and gravel between two channels has K=0.1 cm/s and is supplied from a ditch ho=6.5 m that penetrates to the bottom. If the water in the second channel is h1=4 m deep above the bottom of the stratum, estimate the flow rate From Mays, 2011, Ground and Surface Water Hydrology

Unconfined aquifer between two rivers An unconfined aquifer of clean sand and gravel is located between two fully penetrating rivers. K=10-2 cm/s. L=460 m, W=1.6 m/yr, h1=10 m, h2=8.5 m, ne=0.35 Estimate Maximum elevation of the water table Daily discharge per km from the aquifers into each river From Mays, 2011, Ground and Surface Water Hydrology

Unconfined aquifer flow equation with recharge 𝑞=−𝐾ℎ 𝜕ℎ 𝜕𝑥 =−𝐾 𝑑 𝑑𝑥 ℎ 2 2 𝑞+ 𝑑𝑞 𝑑𝑥 𝑑𝑥 𝑞 𝑊𝑑𝑥 𝑑𝑞 𝑑𝑥 =𝑊 𝑑 2 𝑑 𝑥 2 ℎ 2 2 =− 𝑊 𝐾