Irrigated agriculture is the means of ensuring household, national and global food security, hence a driver for socio-economic transformation. Harvested rainwater, river flows and groundwater are used for irrigation to reduce the risk of crop failure during periods of drought. Nevertheless, this activity has significant effects on the environment. This chapter assesses the environmental impacts of irrigation projects. It highlights the approaches of undertaking an environmental impact assessment (EIA) and then specifically focuses on irrigation projects in Zimbabwe. The study has shown that an EIA is a process which directs project development and addresses the environmental impacts before they occur. An EIA as a tool aims to achieve the desired balance between development and environmental protection. It does not inhibit but enhances sustainable development. It becomes prudent to carry out EIAs so as to identify the socio-economic and biophysical impacts of irrigation development projects and clearly outlines the measures to mitigate the negative impacts caused during project construction, implementation and decommissioning.