Research Article
Adindu Ruth. U, Igboekwe Magnu
Abstract
The groundwater recharge at Umudike watershed was estimated for the year 2012 using soil water balance method. The watershed was divided into zones (blocks). The annual effective rainfall was 1909.8mm. Total number of rainfall days was 146. Peak months for rainfall were July and September. Evaporation peaked also in July with the value of 10.55mm. Runoff was observed to be higher than both cumulative infiltration and recharge. It ranged from 1656.8mm - 1866.8mm Potential evapotranspirtation was calculated to be 46.7mm.. Infiltration varied within the watershed. Male Hostel Block had the highest value (25.5cm) while Admin. Block has the lowest value (4.3cm). Other values include 20.1cm for Female Hostel, 15.3cm for science block and 13.9cm for poultry. 12.87cm layer of water was the highest amount of recharge. This occurred in the Male Hostel Block. Female Hostel Block had a recharge value of 12.07cm while no recharge occurred in both Admin and P.G Hostel Blocks. Other values were 3.05cm in the science block and 1.59cm in poultry/engineering block. Recharge was influenced by infiltration, runoff and the storage capacities of both the surface soils and sub soils.