It has been 60 years since the uMfolozi River was separated from the St Lucia system for whatever reasons at the time made sense, altering the freshwater inflow into St Lucia, and affecting the natural river mouth dynamics.
Hotly debated ever since, the river has finally been rejoined enabling the natural restoration and rejuvination of the estuarine system.
In 2011 iSimangaliso publicised its strategy to let the uMfolozi River and Lake St Lucia rejoin in a bid to restore the functioning of South Africa’s largest estuarine system.
These factors, combined with below average rainfall conditions during the 2002 – 2010 period, have resulted in the St Lucia estuary mouth remaining closed to the sea for the best part of the last decade. This has meant that St Lucia has not functioned as an estuary and fisheries, such as the inshore line fish and crustacean fisheries, have been heavily impacted.
The relinking of the uMfolozi river back to the St Lucia estuarine lake system is an important first step towards the restoration of estuarine function.
Since the beginning of summer the uMfolozi has migrated naturally northwards from Maphelane towards St Lucia. As winter approached and water flows in the uMfolozi dropped this migration slowed and the uMfolozi reached to within 300 m of the St Lucia mouth. This placed the system in a good position for iSimangaliso to facilitate the linking of the two systems.
The conditions in the combined system will continue to be closely monitored during this important time. The current salinity profile from north to south still represents a reversed salinity gradient not normally found in South African sub-tropical estuaries.via iSimangaliso news flash