Conservation

OVERSTRAND ESTUARIES IN CRISIS

Posted on the 22nd March 2010

OUR ESTUARIES IN CRISIS!

Much has already been written in the Hermanus Times about the critical condition of the Overstrand’s river estuaries. The level of pollution in the Klein, Bot-Kleinmond, Onrus, and Uilkraal river estuaries has rendered these unsafe for recreational use over the summer months. What is more worrying is that there is grave concern amongst the scientists who have investigated the situation that the “tipping point” may have been reached beyond which a large loss of natural habitat, biota and basic ecosystem functions will occur. This has extremely serious implications for eco-tourism and for the near shore fisheries for which these estuaries provide fish nurseries. Even the abalone farms in the Hermanus Harbour saw detrimental effects suspected to be associated with toxic sediment flushed out of the Klein River estuary during the last breach. Something has to be done, but what and by whom?

While South Africa has excellent environmental legislation that should ensure that our rivers, estuaries and coastal zones are well managed, the management actions of the various agencies mandated under this legislation has been unco-ordinated and is ineffective. The need to provide co-ordination has been recognised and a process is underway to institute management forums to fulfil this vitally important coordination role.

A series of “estuary forums” is being set up through the C.A.P.E. Estuaries Programme to co-ordinate the proper management of the estuaries in the Western Cape. In the Overstrand one forum, the Klein River Estuary Forum (KREF), has already been functioning since mid-2009, the Bot River Estuary Forum will be launched in April and others will follow. The programme facilitates the drafting of an estuary management plan (EMP) for each estuary, involving local interest groups (e.g. the Overstrand Conservation Foundation) and representatives from all government agencies and local municipalities that are mandated by various structures of legislation to play a role.

The KREF has begun the task of implementing the draft EMP developed for the Klein River Estuary at a time when the condition of the estuary has deteriorated to the point of crisis. Water flow into the estuary has been depleted by an estimated 25% through excessive abstraction and alien infestation. Mature commercial fish species have been poached to the point where stocks are exhausted, placing the nursery function of the estuary in jeopardy. Faecal coli are at dangerous levels and the water is too polluted for safe recreational use. Nutrient levels are very high, resulting in algae infestation. Dissolved oxygen levels in extensive areas of the estuary are extremely low, resulting in high fish mortality and the risk that the estuary may become anaerobic, killing all marine life. Click here to view photographs.

In order to find direction under the critical conditions, the KREF held a workshop to which scientists, who are expert in various aspects of estuarine management, were invited. The main findings of this workshop were presented to the Overstrand Mayor and Municipal Manager on Monday 15th March. These include the following:

  1. Implement the EMP. The KREF must drive this, including ensuring that proper monitoring of key ecosystem health indicators are reinstituted in a co-ordinated way and that targeted research is done to understand and halt deteriorating trends seen in routine monitoring.

  2. Determine the “ecological reserve” (water quantity and quality flowing from the catchment area into the estuary) required to achieve the required A/B ecological status rating for the estuary. This must be done by the Department of Water Affairs.

  3. Urgently confirm the source(s) of faecal coli pollution and plan removal of sources. A study by Dr Vic Hamilton-Attwell recommended that work must be done to confirm expert opinion that a bacterial biofilm has formed in the ground between sewage treatment systems and the estuary, and that this is the main cause of faecal coli pollution of the estuary. The Municipality needs to commission work to confirm this and address the problem if this proves to be the source.

  4. Plan to relocate sewage treatment installations above the recommended setback line of 5m above msl. These installations were identified in a survey by Hamilton-Attwell during his study and his report recommended their relocation. The Municipality needs to confirm the 5m above msl contour setback line and enforce compliance.

  5. Determine sources of eutrofication and manage these. Eutrofication sources may include sewage treatment works, farming activities and agri-industry, and the brewery. The Department of Agriculture and the Municipality need to investigate and address aspects of this in a co-ordinated way.

  6. The estuary mouth must be managed to ensure that natural breaching is able to occur at 2.6 – 3.1m above msl. Research has shown that artificial breaching at lower water levels does not flush sediment that harbours toxins out of the estuary. The KREF must lead this process which needs to be implemented by Cape Nature with Municipal co-operation.

  7. The estuary needs to be registered as a protected area under the RAMSAR convention. Cape Nature needs to carry out this registration process with the support of the Municipality.

The Mayor indicated his general support for the approach of the KREF and undertook to consider the recommendations as they affect the Municipality. He asked for a budget estimate for the work to confirm that a bacterial biofilm is infecting the estuary so that he can seek funding from the provincial government to conduct the investigative work.

The tragedy of the Overstrand estuaries is that none of the government agencies have allocated adequate budgets or resources to perform the work that must be done to properly manage these estuaries so that they do not progressively deteriorate. The KREF has no funding and all non-government parties perform the work on a voluntary basis. While we watch our estuaries degrade to polluted liabilities, the cry from our Municipality is “unfunded mandate” and from other government agencies “provide us with motivation for budget allocations.” Who must provide the motivations? Unfunded civil society organisations such as the Overstrand Conservation Foundation? Can we afford this work … can the Overstrand afford for us not to perform this work?

Rob Fryer, OCF Manager & KREF Chairman.

 

 



COMMENTS

106
JOHN WILLIAMS (posted: 2011-01-13)
Congratulations very good work done. I suggest that point 4 be edited as follows.
4. Plan to relocate sewage treatment installations and privatly owned septic tanks above the recommended setback line of 5m above msl. These installations were identified in a survey by Hamilton-Attwell during his study and his report recommended their relocation and adherance to CSIR standards. The Municipality needs to confirm the 5m above msl contour setback line and enforce compliance. A survey of the estuary needs to be commissioned showing the setback line to this effect.