Ulwandle Autumn 2011
"KwaZulu-Natal's Coastal Management Newsletter" To view other Ulwandle newsletters cl...
An unpublished thesis by a city engineer, Stefano Corbella, has discovered that the shape of KZN beaches was likely to alter over time due to an increased change of wind and wave action.
“Climate change is resulting in an increase of wave energy and an imbalance in the seasonal cycle. The more energy in a wave, the more it erodes against the sandy strip of the beach,” said Corbella’s supervisor, Andrew Mather, a department engineer who has also done research into rising sea levels and coastal erosion.
Corbella, who recently graduated with a masters degree in coastal engineering from the University of KwaZulu-Natal, could not be reached for an interview yesterday, but Mather spoke highly of his work.
“This research will provide information at our fingertips, which will assist in long-term planning of coastal developmental projects,” he said.
An increase in wave energy over time would result in a “beach retreat” – an erosion and displacement of sediments – said Mather, who is also in charge of the city’s coastal policy projects.
“Over a period of years, the beach will become much narrower and water will move more inland.”
A change in wind direction, also caused by climate change, would affect the profile or shape of the beach, he said.
Meanwhile, a new interactive, computer-based tool was launched on Tuesday to assist coastal managers in identifying areas along the coast that were “vulnerable” to erosion and rising sea levels.
The Coastal Vulnerability Index (CVI) was developed in partnership with the Department of Agriculture, Environmental Affairs and Rural Development and the Oceanic Research institute (ORI), with other local stakeholders.
“Our principle objective was to inform management of areas identified as at risk, as well as potentially at risk,” said ORI scientist, Bronwyn Palmer.
In addition to levels and locations of vulnerability, the index would also identify sensitive ecological areas and sites of known historical erosion, said Palmer.
From data measured by the index, KZN showed an alarming 47 percent at moderate risk and 23 percent at high risk in coastlands, the higher ranking areas falling more on the South Coast.
Described as a “breakthrough in technology”, the tool would be distributed free of charge.
KZN MEC for Agriculture, Environmental Affairs and Rural Development, Lydia Johnson, said that the department would ensure that coastal management principles and practices were incorporated into municipalities’ and districts’ development plans.