South Africa - Coastal and Marine Economy: Can It Be Salvaged From the Impacts of Poor Water Quality?
South Africa has one of the highest unemployment (currently above 31% and growing, worsened by Covid-19), poverty stricken and unequal societies in the world.
Estuaries and marine ecosystems contribute between R4.2 and R10bn per annum to the South African economy. However, the development of estuaries and their catchments has come at a cost of about R700m per annum in terms of lost fishery benefits as well as unknown costs to society from the overexploitation of natural resources, including biodiversity.
Beaches retain blue flag status in as long as their waters are clean and healthy for use in recreation. Clean water of acceptable quantity must reach these estuaries and beaches via the inflows from river catchments.
This balance is critical and required by the estuaries as nurseries for many of the marine fish species that local and fisherman rely upon. This represents a huge ocean economy that is under threat from ecosystem degradation. Despite the role of the coast in livelihood of many citizens, these ecosystems are particularly vulnerable.
Deteriorating water quality is driving most of the changes. There have been a significant increase in pollution pressures from wastewater treatment works (WWTW) discharges, amplified by a decreasing ability to treat effluent to required standards. This is further exacerbated by rapid urbanisation, leading to increase storm water discharges. Increased nutrient loading is causing severe eutrophication, resulting in low oxygen levels, and decreasing estuary productivity and important ecosystem services they provide, such as nursery function.
In most extreme cases it causes noxious algal blooms and fish kills. In the long run, it affects recreation value and property values and reduces business opportunities. Poor water quality is also affecting resilience and creating opportunities for invasive species. Some of the South Africa’s high energy coastline estuaries provide rare naturally safe environments for contact recreation, such as swimming.