Using Annual Rainfall to Estimate the Surface Runoff and Groundwater Recharge in Lialan Basin (Southeast Kirkuk - North of Iraq)

Abstract

The present study intends to estimate the surface runoff and groundwater
recharge in Lialan basin using the soil conservation service method (curve number)
and chloride mass balance method (CMB) respectively. Lialan basin is located at the
southeast part of Kirkuk governorate, between longitudes (44° 21' 00" E - 44° 42'
00" E) and latitudes (35° 7' 30" N - 35° 28' 30" N) , which covering an area of about
436 km2 and contains many geological formations. In this study, based on the
annual rainfall data extending from (1970 - 2016) obtained from the Kirkuk
meteorological station, the surface runoff was calculated using the curve number
method (CN), and found to be equal to 90.4 mm/year, which represent 26.07 % of
the total rainfall. While the groundwater recharge was calculated depending on the
annual rainfall and chloride concentrations in rainfall and groundwater using the
chloride mass balance method (CMB) and found it equals 23.07 mm/year,
representing 7.42 % of the total rainfall. Thus the annual recharge amount for the
whole basin is equal to 10.0585 × 106 m3 / year. Generally, the results indicate a
direct relationship between the systems of runoff and groundwater recharge in
Lialan basin with total rainfall .