02 Eassy Submarine Cable
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IMPACT ASSESSMENT CASE STUDIES FROM SOUTHERN AFRICA Compiled by Paul Scherzer SAIEA E&D Consulting Services Client: Telkom SA Southern African Institute for Environmental Assessment ... working for a better Africa ROUTING OF THE EASSy SUBMARINE CABLE, SOUTH AFRICA Compiled by Paul Scherzer E&D Consulting Services Client: Telkom SA ROUTING OF THE EASSy SUBMARINE CABLE, SOUTH AFRICA Aims of the Project Brief description of the development and alternatives considered Telkom SA operates existing submarine fibre- Submarine telecommunication cables form a vital optic telecommunication cables in South African part of the global communications network. Fibre waters from two landing locations, one on the optic cables are essentially tiny glass fibres which west coast and the other at Mtunzini on the east. transmit digital pulses converted by computers at The South Africa Far East (SAFE) submarine cable was landed at Mtunzini in 2001. The existing cable station and shore-based infrastructure at Mtunzini had capacity for an additional cable. Telkom SA proposed to land another cable, the East Africa Submarine System telecommunica- tions cable (EASSy), on the main beach of Mtunzini. The aim of the proposed EASSy cable was to Figure 2: Illustration of cables enhance telecommunication links along the east and increasing levels of armouring coast of Africa, as this region relies exclusively on satellite which is expensive and limited in capacity. each end of the cable. A typical lightweight cable has a 17 mm outer diameter and comprises a welded steel tube housing multiple fibre pairs in a stress-free environment. In order to protect the cable, depending on the level of risk, the number and diameter of armour wires surrounding the cable is increased, with a high strength double armoured cable having an outer diameter of Figure 1: Route of the proposed EASSy cable approximately 45 mm (Figure 2). down the east coast of Africa. © SAIEA 2009 1 Compiled by Paul Scherzer E&D Consulting Services Client: Telkom SA ROUTING OF THE EASSy SUBMARINE CABLE, SOUTH AFRICA Brief description of the development and alternatives considered The routing and laying of a submarine mountain slopes and deep trenches below the Importantly, one survey ship is contracted to telecommunication cable is preceded by detailed ocean, areas of heavy shipping and rocky eroding undertake the survey for the entire cable and all planning involving market capacity and marine beaches as landing points. the landing locations. Thus, due to the distances cable routes, as well as negotiation between and costs involved, the survey is undertaken various international telecommunication service The greatest danger to communication cables is according to a programme that is relatively providers regarding financial contributions and from bottom contact fishing methods performed inflexible in terms of accommodating last minute market share. In order to select the optimum route by trawlers. For this reason Telkom stipulates a changes or repeating parts of the survey to for a submarine cable a range of marine charts, no trawling or anchoring zone for one nautical consider other locally proposed alternatives. regional bathymetric data, seabed topography and mile on either side of their submarine cables. geology sources are consulted. Information must Due to the fact that Telkom had an existing land- also be gathered from relevant government An international cable company is appointed to based cable station at Mtunzini with spare departments, telecommunication companies and undertake the planning and implementation of the capacity, alternative landing sites were not other groups such as marine oil and gas companies. entire cable. Once initial desktop routes have been considered for the proposed EASSy cable. planned a detailed marine survey is undertaken, However, one of the key stakeholder groups which Due to the cost of laying and repairing cables at particularly in shallower waters (less than 1,000 objected to the laying of the initial SAFE cable sea, route planning considers cable safety and m deep) where the cable approaches the landing at Mtunzini was the prawn trawling industry aims to avoid, among other aspects, steep station. The purpose of the survey is to optimise operating out of Durban. The SAFE cable the position and laying of the cable traversed both the in-shore and off-shore trawling to avoid high risk areas and to grounds and for various reasons at the time an finalise the design and protection alternative alignment to miss these trawling required for the cable. A survey is grounds was not feasible. A legal dispute between then taken of an area approximately the Prawn TrawlerÕs Association and Telkom 1 km wide along the identified occurred after the environmental authorisation route, and thereafter the final cable process and laying of the SAFE cable. position is optimised within this surveyed band. Figure 3: Landing of the SAFE cable at Mtunzini © SAIEA 2009 2 Compiled by Paul Scherzer E&D Consulting Services Client: Telkom SA ROUTING OF THE EASSy SUBMARINE CABLE, SOUTH AFRICA Environmental setting The KwaZulu-Natal prawn trawl fishery consists prawn stocks found on the Thukela Banks, as this grounds. The prawn species targeted on the of two components: an inshore fishery, referred species is dependent on estuaries for their nursery offshore fishing grounds are species which are to as the Thukela Banks, and an offshore fishery not dependent on estuarine habitats during their (Figure 4). Trawlers can fish from March to lifecycle and, thus, had not been affected by the August on the Thukela Banks and year round on closure of St Lucia. the offshore grounds. Different species are caught at these respective grounds. An important socio-economic impact was that the existing trawling companies were concerned that Importantly there are few areas off the South any additional loss of trawling grounds would African coast suitable for shallow water penaeid further reduce the grounds and catches and, thus, prawn trawling due to the very narrow continental the economic viability of the trawling industry. shelf, particularly in the sub-tropical areas of northern KwaZulu-Natal which are the only areas There are only specific areas off the KwaZulu- warm enough to support a breeding population. Natal coast which are suitable for prawn trawling. The Thukela Banks fishing grounds support the Apart from the climatic conditions and sea-floor southernmost commercial prawn fishery in the conditions suitable for prawns, trawling needs to western Indian Ocean. occur in areas where there are no reefs which can snag fishing gear, and in areas large enough to Fishing rights had been allocated from 2006 to make it economically and practically viable to 2013 and were held by four fishing companies. trawl. It is not practical for trawlers to simply lift However, general opinion was that the trawling their nets over an obstacle, drop them again and industry was struggling to remain economically continue. So the trawlers will not operate in an competitive due to reduced catches as a result of area that is too small to obtain a reasonable catch the closure of the St Lucia estuary mouth and in one trawl. cheap imports. The closure of the St Lucia estuary mouth was considered to be having a significant Figure 4: Prawn trawling grounds For these reasons the trawl grounds, particularly negative impact upon the shallow water penaeid off KwaZulu-Natal the Thukela Banks, were identified as an © SAIEA 2009 3 Compiled by Paul Scherzer E&D Consulting Services Client: Telkom SA ROUTING OF THE EASSy SUBMARINE CABLE, SOUTH AFRICA Environmental setting EIA process followed environmental and economic resource which, The EIA process went through a Scoping Phase During the Scoping Phase, meetings were held regardless of current catches and cheaper imports, followed by an Impact Assessment Phase. with representatives of trawling companies to remains an important resource for conservation. discuss the proposed cable route. Various concerns Thus, whilst the actual size and operation of a were raised that the cable would further dissect submarine cable has practically no impact on the Scoping Phase public participation the Thukela Bank fishing grounds. Representatives actual prawns, the resource would be impacted if provided specific coordinates of the fishing the cable route resulted in the grounds being From the outset, the client was concerned that grounds. These positions were communicated to divided up into sections too small to viably trawl. appeals or legal disputes from the trawling the client who in turn requested the international industry would either delay environmental cable route team to consider an alternative route. authorisation or project implementation. The An alternative cable alignment was considered process was therefore designed to ensure that the and proposed. trawling industry was provided with maximum opportunity to comment and participate, and that off-shore cable route alternatives could be Specialist study considered. In order to ensure that the best cable route alternative could be selected, the The Oceanographic Research Institute was environmental consultant ensured that the process appointed to undertake a specialist study focusing of stakeholder consultation would align with the on the impacts of different cable routes upon the programme of the international cable route team trawling grounds and industry. The data used was who were planning the routes and the marine the most accurate data available