A vast seasonal wetland network of shallow channels defining north-central Namibia.
Oshana System
The Oshana System, also known as the Cuvelai System or Cuvelai Wetland, is one of the defining geographical features of north-central Namibia. It is a broad, branching network of shallow, low-gradient drainage channels known locally as iishana (singular oshana) that flow in a generally north-to-south direction across the eponymous Oshana Region. The system originates in southern Angola on the Bié Plateau and terminates at the northern shore of the Etosha Pan, spanning from Ruacana in the west to Ondangwa in the east.
The landscape is shaped by the seasonal flooding cycle known as the efundja. After heavy rains in Angola and northern Namibia, the channels fill with water and overflow into surrounding depressions, transforming more than 30,000 square kilometres into a temporary wetland, the largest freshwater habitat of its kind in the country. During dry periods, the oshanas become open, grassy, mostly vegetation-free pans bordered by mopane woodland and makalani palms.
Beyond its ecological role, the Oshana System is the lifeline of the Ovambo people, supporting subsistence farming, livestock grazing, and traditional fisheries during flood periods. Because the sandy soils of the region retain little moisture, floodwater is essential for recharging groundwater, sustaining pastures, and enabling cultivation of maize, millet, melons, and beans. Today, increasing settlement pressure in flood-prone areas has made the region vulnerable to both drought and increasingly damaging floods.
