Hitungan SPAHD = durasi hujan (jam)I = intensitas hujan (m/jam)At = luas tanah tadah hujan tanpa atap (m2)K = permeabilitas tanah (m/jam)P =keliling penampang sumur (m)As = luas penampang sumur (m2)

Diameter SPAH= 1 mFreeboard= 0,5 mD= 0,5 jamI=19 mm/jam = 1,9.10-2 m/jamAt= 464,76 m = 465 mK= 4,167.10-8 m/jamP= 3.14mAs= 0.785 m2

H =

= 5.6 m Kedalaman SPAH = H + freeboard= 6.1