St Francis Bay Beach

KOUGA Municipality has arranged to make monthly pro-rata payments to SIC Denmark for the lease of the PEM system, ongoing until the end of the five-year contract.
The system is still fully on track and has been throughout, as the Danes continued with their commitment without a break, even though payments were in arrears for a considerable time.
The January GPS survey by Maarschalk showed that the sand volume in the PEM target area was up to 68883.5m³, way above the 41841.6m³ datum recorded at the start of the project in November 2008. This great result is in spite of the severe storms and erosion of last year.
I did a routine inspection again on Friday (February 10) and found the beach to be generally in excellent shape. It is indeed very wide at low tide, having withstood the recent strong on-shore easterly winds and waves which were rough enough to uproot mounds of seaweed and red bait from the sea floor and deposit these on main beach.
It is also interesting to note the extensive sand banks building up in the shallows just off shore.
These extend most of the 2600m length of the PEM system installation and in places are up to over 45m out beyond the low tide mark.
This additional volume of sand was of course not included in the official survey volumes as it falls outside the last line of surveyed filter positions. It is however accumulated there and available to be picked up in the wave action and trapped higher up the beach by the filters, given favourable weather conditions. Assuming we do not have a real buster hitting us again soon, the next GPS survey should show even better sand levels on the beach. Let’s hope this happens.
I must once again stress – the PEM system is contracted and designed to prevent any further erosion from the November 2008 measured beach datum. PEM works by trapping sand carried in suspension in the waves as they wash onto the beach. This has been achieved well beyond the contract requirements, as surveys have proved. In this way it builds a buffer of trapped sand in good conditions, which erodes in storm weather, leaving the base datum intact.
Unfortunately the system cannot make sand to rebuild the beach entirely. The past supply source of sand from the Santareme dunes no longer exists and the Kromme no longer floods carrying the Sand River supply to sea. Therefore it can never rebuild the beach to the great levels of 20 years ago. But we are now stabilised and no longer loosing additional sand.
No matter what system is proposed – PEM, groynes, reefs, revetments, or whatever else – none can make sand. Sand would need to be imported from elsewhere by truck or dredger, to rebuild the beach we had years ago. The Danish system has at least been able to maintain what we do have, at minimal cost. Permanent rebuilding can and has been done elsewhere. But funding – that is the big question.
Meanwhile I see a lot of folk who are very happy with our wider beach. Only complaints have been from fishermen who must now wade far out in the shallows to find deeper water.
Neil Brent

Leave a Reply

Please keep in mind that comments are moderated according to our comment moderation policy. Your email address is required but will not be published.