WSE3701 Assignment 01 Answers Year 2025

Water and Sanitation Engineering III

Assignment 01 Answers

Year 2025




0027 63 985 5033

,
,
, QUESTION 1

Given data:

𝑃𝑢𝑚𝑝𝑖𝑛𝑔 𝑟𝑎𝑡𝑒, 𝑄 = 2500 𝑚3 /𝑑𝑎𝑦

𝑇𝑟𝑎𝑛𝑠𝑚𝑖𝑠𝑠𝑖𝑣𝑖𝑡𝑦, 𝑇 = 280 𝑚2 /𝑑𝑎𝑦

𝑆𝑡𝑜𝑟𝑎𝑔𝑒 𝑐𝑜𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑡, 𝑆 = 4.0 × 10−5

𝑃𝑢𝑚𝑝𝑖𝑛𝑔 𝑑𝑢𝑟𝑎𝑡𝑖𝑜𝑛 = 5 𝑑𝑎𝑦𝑠

𝑅𝑎𝑑𝑖𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒, 𝑟 = (0.2𝑚, 100𝑚, 200𝑚)



Theis equation for transient flow in a confined aquifer is given by:

𝑄
𝑠= 𝑊(𝑢) 𝑤ℎ𝑒𝑟𝑒:
4𝜋𝑇

𝑊(𝑢) = 𝑊𝑒𝑙𝑙 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛,

𝑎𝑝𝑝𝑟𝑜𝑥𝑖𝑚𝑎𝑡𝑒𝑑 𝑎𝑠 𝑊(𝑢) ≈ 𝐸𝑖(−𝑢) 𝑤ℎ𝑒𝑟𝑒 𝐸𝑖 𝑖𝑠 𝑡ℎ𝑒 𝑒𝑥𝑝𝑜𝑛𝑒𝑛𝑡𝑖𝑎𝑙 𝑖𝑛𝑡𝑒𝑔𝑟𝑎𝑙 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛



u values for different distances;

𝑟2𝑆
𝑢= 𝑤ℎ𝑒𝑟𝑒:
4𝑇𝑡

𝑟 𝑖𝑠 𝑟𝑎𝑑𝑖𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒

𝑆 𝑖𝑠 𝑠𝑡𝑜𝑟𝑎𝑔𝑒 𝑐𝑜𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑡

𝑇 𝑖𝑠 𝑡𝑟𝑎𝑛𝑠𝑚𝑖𝑠𝑠𝑖𝑣𝑖𝑡𝑦

𝑡 𝑖𝑠 𝑝𝑢𝑚𝑝𝑖𝑛𝑔 𝑟𝑎𝑡𝑒



𝐹𝑜𝑟 𝑟 = 0.2𝑚 (𝑊𝑒𝑙𝑙 𝑟𝑎𝑑𝑖𝑢𝑠)

(0.2)2 × (4.0 × 10−5 )
𝑢=
4 × 280 × 5

𝑢 = 2.857 × 10−10