Assessment of the Environmental Impacts of the Hejda-Nahr Diversion Dam in Balkh Province

Abstract

Afghanistan, due to its relatively arid climate, limited precipitation, and steep topography, faces serious challenges in water resources management. Therefore, the construction of dams and water control structures plays a significant role in economic development, flood management, and the distribution of water resources. Despite the economic importance of these structures, assessing their environmental impacts is also considered an essential requirement for sustainable water resources management. The present study aims to investigate the environmental impacts of the three diversion dams of Nahr-e Shahi, Samarqandian, and Bangala located in the Eighteen-Nahr (Hashtdah Nahr) area of Balkh Province.

This research was conducted using a descriptive–analytical approach based on both library and field studies. The statistical population consisted of residents and beneficiaries of the areas affected by these dams, and samples were selected using a spatial cluster sampling method. Data were collected through researcher-designed questionnaires, interviews, and field observations and were subsequently analyzed.

The findings indicate that the studied diversion dams have had a significant impact on reducing flood-related damages, facilitating water management and distribution, decreasing conflicts over water rights, preserving part of the region's biodiversity, and improving the management of irrigation canals. The results also reveal that, due to their diversion and regulatory nature, these structures have not contributed to increasing seismic hazards in the region. However, their effects on groundwater recharge, tourism development, and the full realization of equity in water rights distribution have been assessed as limited. Overall, the diversion dams of Eighteen-Nahr have played an effective role in improving water resources management and mitigating some of the environmental and social challenges of the region; nevertheless, enhancing their efficiency requires complementary planning and management measures.