In January last year, tons of sand were cleared away to link Lake St Lucia with the ocean for the first time since 2014 — a move that sparked outrage among some scientists, and prompted government to launch a probe.
Last week, the findings of the report into the consequences of the artificial breach of the estuary, which was carried out by the Isimangaliso Wetlands Park, were released.
The report found that there were some ecological benefits to the breach – but some problems remain unsolved.
Here are some of the factors at play:
What happens when the estuary mouth is closed?
The St Lucia estuary is located in the iSimangaliso Wetland Park, on the east coast of KwaZulu-Natal. It is the largest estuarine lake in southern Africa and covers an area of 350km2.
In 1999, Unesco declared the estuary South Africa's first natural world heritage site.
The estuary collects water from feeder rivers - uMfolozi, uMsunduzi and Mkhuze.
It serves as a nursery habitat for young marine animals. Larger animals like crocodiles, hippos and birds also live in the estuary.
The estuarine mouth closes up due to a collection of sediments (given that it is a catchment area). The accumulation of sediment has been an ongoing challenge.
The mouth closure makes it difficult for fish to move in and out of the estuary - reducing fish catches and biodiversity and also affecting the nursery functions of the estuary. Researchers also observed an increase in alien invasive species or vegetation resulting from the mouth closure.
In addition, the mouth closure affects the salinity of the water. When the mouth is closed, the estuary system becomes dominated by freshwater species as estuarine and marine species cannot tolerate low salinity in the water. There's also a decrease in hippos, crocodiles and birds.
Communities that rely on the estuarine system are also negatively impacted. For example, the report indicated that heavy rainfall leads to back-flooding affecting commercial and small-scale farms in the uMfolozi catchment area. Other impacts of the flooding include mosquito infestations. Tourism activities are also negatively impacted.
What led to the opening of the estuary mouth?
There have been attempts to breach the estuary mouth artificially since 2015, when the uMfolozi Sugar Planters and other sugarcane farmers lodged an application with the KwaZulu-Natal High Court. They were hoping to bring relief from the flooding of their farmlands.
In 2018, the high court dismissed their application.
Then in late 2020, a large workshop was held with commercial farmers, community representatives, scientists, government officials and others to determine the best way to breach the estuary mouth - to flush out the silt collected from the uMfolozi River.
In January 2021, iSimalango Wetland Park carried out the breach - based on advice from a scientific and technical task team. By June 2021, the mouth closed again. (Following the recent heavy rainfall and flooding in KwaZulu- Natal, the mouth was naturally breached.)
The artificial breach was questioned by some scientists, who wrote an open letter to Barbara Creecy, Minister of Forestry and Fisheries and Environmental Affairs, demanding an explanation.
The scientists noted that the breach went against advice from a 2015 report funded by the Global Economic Fund, which indicated that human or artificial breaches should be minimised.
The scientists requested an independent investigation into the impact of the breach. The minister then appointed an independent panel of experts in October 2021 to investigate the impact of the breach. The panel was also mandated to make recommendations for the future management of the system.
Did the breach make a difference?
The opening of the estuary mouth positively impacted the estuary and wetland system by restoring its nursery functions, the report found. Some marine fish were reintroduced to the estuary, which is beneficial for tourism and recreational fishing. Hippos also returned to the estuary mouth.
However, there were no observed changes when it came to removing sediment, vegetation like reeds and alien invasive species. There was also no benefit for small and large-scale farmers impacted by back-flooding.
"Back-flooding, which was the main concern, did not subside, and social issues associated with back-flooding persist," the report read.
What are the recommendations of the report?
The review indicates that exceptional circumstances warranting an artificial breach be more clearly defined and should take into account ecological and social factors. The review also proposes a monitoring plan be developed, to ensure the breach is done at appropriate times and in optimal conditions.
It also called for better communication between stakeholders, especially for communities to understand decisions related to the management of the estuary.
There is also a view that the input from black communities, especially in policy decision-making, is not taken seriously. The report indicates that communities need to be "fully involved" in the management planning of the estuary - as it impacts their livelihoods in the long term.
Creecy said that conservation of the environment must involve communities. "Unless communities living on outskirts feel they are heard and involved in the management and unless benefit from management - conservation areas will always be at risk," said Creecy.
The review highlighted that communities do not feel an effort has been made to communicate the highly technical issues surrounding the estuary mouth closure in an understandable way.
"This has a negative effect on communities participating and making informed strategic decisions," the report read. "Communities cannot participate in technical discussions - which contributes to conflict between stakeholders and resentment towards management authorities and Unesco."
There were some concerns that the wetland would lose its world heritage status.
"We have no intention of losing our World Heritage status," Creecy made clear last week. The ecological and economic value of the system stems from its world heritage status, Creecy explained. The estuary is a tourist attraction which has supported economic activity and job creation. "We would absolutely not want to lose that status."
What are the next steps?
The report found that the management of the system could not be left to the iSimangaliso Wetland Park Authority alone.
The activities in feeder rivers all contribute to the health of the St Lucia system.
A management plan will be developed which will involve government departments such as agriculture, land and rural development and water and sanitation. There should also be more collaboration with district and local municipalities. Creecy also requested some members of the panel continue work for six more months to monitor and advise on the implementation of recommendations.