Water Harvesting in South Jabal Al Akhdar Between Investment and Reducing Damage to Natural Resources

Abstract

Water resources pose a prominent societal concern, encouraging the implementation of water development plans and programs; consequently, it is crucial to attentively manage rainwater and land appropriately to secure environmental, agricultural, and social stability for the population. In light of the above, this paper sought to explore a reservoir and a stone dam located south of Al Jabal Al Akhdar, evaluating their capacity to store runoff water, soil conservation, and their role in development endeavors. The results indicated that a 1200 m³ capacity reservoir, designed according to specific scientific standards, encompassing a catchment area of approximately 5.5 hectares and receiving an average annual precipitation of 283 mm, has successfully provided drinking water to 10 families following the Libyan Specifications S 82/2015 over 5 months. Establishing a 75 m³ stone dam on a watershed of 24.5 hectares facilitated the retention of almost 640 m³ of water, supporting livestock watering, improving the environmental situation around the dam, and depositing an estimated 1800 m³ of soil. It also enhanced the infiltration rate to 0.9 cm.hr⁻¹, compared to about 0.4 cm.hr⁻¹.. In the reservoir's catchment area. The infiltration function known as the ∅ index signifies the soil's capability to absorb water over a given duration. Runoff occurs if the value exceeds the ∅ index. The fluctuation in the ∅ index value is pivotal in determining the nature and quantity of runoff, augmenting rainwater utilization on the Al Jabal Al Akhdar, and minimizing flood risk through water retention. This, in turn, aids environmental equilibrium, mitigates disasters, provides stability for the local population, preserves natural resources, and supports water security initiatives.