| Egypt | ||
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| The Nile Delta is built of sands carried to Egypt's Mediterranean coast by the Nile River, primarily since the end of the last ice age. Dams along the river and entrapment of sediment in a vast network of irrigation canals have led to a dramatic decrease in the flow of water and sediment to the delta's edge. Closing of the Aswan High Dam in 1964 shifted the balance between sedimentation and erosion in favour of erosion. At several points along the coast, the delta is now receding. Damietta Promontory has eroded dramatically as waves and currents have stripped its sands faster than the river can replenish them (yellow arrow). While there are local areas of accretion such as the Damietta Spit (red arrow), on balance the delta is shrinking. Prior to the construction of the Aswan High Dam, fresh water from annual floods influenced salinity and circulation patterns up to 80 km offshore from the delta. In contrast, current discharge patterns allow salt water from the Mediterranean to reach dams up to 26 km inland. Diminished freshwater and sediment delivery to the delta also affects the ecology of coastal lagoons, soil fertility, and salinisation of irrigated land. Coastal protection structures, regulation of irrigation, and increased groundwater exploitation may mitigate the delta's decline, but the current rate of population growth threatens to outstrip these measures. View detailed information | ||
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