EThekwini Municipality’s coastal engineer and sea level rise expert, Dr Andrew Mather from Durban, South Africa has designed a two day coastal engineering training workshop in response to capacity building requirements expressed by city counterparts in Tanzania.  The first test run of the workshop was held in November 2014 in Dar es Salaam, Tanzania and was attended by local government officials with engineering backgrounds from nine coastal local governments in Tanzania.

The purpose of the coastal engineering training workshop was to provide an opportunity for local government officials to learn directly from another local government official tackling similar problems in their own city. The need for the training was identified as a result of several exchanges between Durban and Dar es Salaam that have taken place as a result of their joint involvement in the Durban Adaptation Charter (DAC).  Both cities experience coastal protection challenges, however as a result of access to more resources, Durban has dedicated staff dealing with coastal management challenges.  In addition, coastal management challenges are expected to increase in the face of climate change which is expected to result in sea level rise as well as increases in coastal storms for both cities. 

The first day of the workshop was dedicated to providing an overview of the processes that shape coastal development, beach materials, and the causes of coastal erosion. The second day focussed on practical examples and began with several local governments describing some of their key coastal management challenges.  Three of these challenges were then reviewed in more detail by participants in order to apply some of the knowledge gained during the previous day:

Mafia Island:

The Mafia Island representative reported that one of their main challenges is the erosion of the sandy beaches on the west side of the island. The participants examined aerial photographs of the area and Dr Mather highlighted that the island was experiencing natural movement of sand from north to south.  As a result the beaches on the west side of the island were naturally eroding.  Since the area of erosion is extensive, Dr Mather indicated that it would be very expensive to put in place measures to protect the entire area so he recommended picking priority areas.

Kinondoni Municipality:

Kinondoni Municipality representatives indicated that coastal erosion that is threatening roads and other developments in the municipality was their key coastal concern.  The participants examined aerial photographs of the area and Dr Mather highlighted that problems were being experienced in areas to the north of rivers. He explained that areas to the north of the rivers are naturally in flux. Normally this would not be a problem in the natural world, but since there is development in these areas it creates a challenge.  He also noted that because sediment was being dredged from the harbour in the south, it was starving the areas to the north of sand and contributing to the erosion. Some of the solutions discussed included the establishment of protective structures to rebuild the beach behind the structures and also the re-nourishment of the beaches with sand that is dredged from the harbour. 

Bagamoyo:

The main challenge being experienced in Bagamoyo is a retreating shoreline. The retreating shoreline threatens a beach front road and important tourism infrastructure. The group examined aerial photographs and a number of possible explanations were discussed, however it was not possible to come to a final conclusion on the causes. One of the contributing factors noted by Dr Mather was the drainage from the road itself.  A possible solution that was discussed was the use of a plastic mesh that could be stretched over an area that requires protection. The plastic mesh could be in-filled with soil and vegetation.

Feedback received from the twelve participants regarding the workshop was extremely favourable. ICMA and the DAC are looking into ways to replicate the training event and to support additional exchange events where Dr Mather can provide expert advice on site to coastal municipalities in Tanzania.

The workshop was conducted as part of the Durban-Dar es Salaam Climate Change Partnership in conjunction with the DAC and the Association of Local Authorities of Tanzania.