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Wise Coastal Practices for Sustainable Human Development Forum
Posted By: Regina Folorunsho
Date: Tuesday, 13 July 1999, at 6:40 p.m.
Key words: sand mining, sea defences.
DESCRIPTION: The Barrier/lagoon complex in Lagos, Nigeria, is part of the Barrier Lagoon system stretching from Cote d'Ivoire to the Niger Delta in Nigeria. It consists of a narrow, low- lying, sandy beach and is backed by the Lagos, Lekki and Ologe lagoons. These lagoons are linked together by many tortuous creeks. Coastal erosion and flooding constitute two of the most devastating environmental hazards affecting this barrier system which harbor about 40% of the urban population, about 12 million people. Victoria Island, a very popular island of real estate and part of this barrier system, is often referred to as the "Hollywood of Nigeria." It is known for high real estate structures consisting of private and commercial buildings fronting the beach. One such prominent building is the College of Fisheries School built and donated by the Japanese Government to Nigeria. The Victoria Beach, one of the most popular beaches and widely used by tourists since the colonial years of 1900, has been the site of the fastest erosion rates in Nigeria and one of the fastest eroding beaches in the world. The rapid erosion rates which characterise this beach, were sparked off with the construction between 1908 and 1912 of two stone moles (east and west moles). The moles were built to protect the dredged deep- water entrance into the Lagos Harbour from intense wave action, and to prevent silting of the entrance by the west to east drifted sand.
Between 1900 and 1959 Victoria Beach has retreated by over 1 km near the eastern mole, while the Lighthouse Beach near the western breakwater on the other hand accreted by over 500 m within the same period. Annual erosion rates of 25 - 30 m had been reported between 1981 and 1985 (Ibe, et. al. 1986). Since 1956, many erosion control measures, involving extension of the groynes and sand nourishment, had been implemented to restore the beach and save the high real estate structures consisting of private and commercial buildings fronting the beach.
Beach nourishment implemented between 1985 and 1986, which involved the dumping of 3 million cubic metres of sand dredged from the nearby offshore area, extended the beach width by an average of 75 m. Following this beach nourishment, erosion continued, averaging 46 m to 110 m at various points on the beach between 1986 and 1995 (Awosika et. al. 1995).
The rapid erosion rate along this beach is caused by the construction of the east and west moles.
STATUS: The most critical area of the Victoria Beach, is the beach fronting the Federal College of Fisheries and Marine Technology buildings worth over 10 million US dollars. (This building and other infrastructure was donated to Nigeria by the Government of Japan). In May 1993 when the building was commissioned the beach was about 150 m wide. By May 1995 the foundation of the buildings was only a few metres from the breaking waves. To protect the buildings, a "T-Groyne? was built in 1995 to protect the college building. This groyne protected the building from being washed away but resulted in rapid erosion along the downdrift side. Due to continual erosion on the downdrift side of the school building, another shore parallel breakwater was constructed between April and June 1999 to protect the eastern part (downdrift side) of the school. Again the updrift side was saved from erosion. But the downdrift side is now plagued by rapid erosion. This "wise practice" is, in my opinion, getting controversial because in one sense the breakwaters are a wise practice and in another sense a bad practice.
DISCUSSION:
LONG TERM BENEFIT: The remedial action taken to solve the beach erosion problem on these critical areas could be termed beneficial, however, it has resulted in transferring the problem to the downdrift side. It is therefore too early to assess how wise in the overall term.
INDICATORS: A comparison of the groyne-protected areas of Victoria Beach and the adjacent beaches shows that the use of groynes on the beach will affect the number of tourists attracted to the beach and reduce recreation activities on the beach.
CAPACITY BUILDING AND INSTITUTIONAL STRENGTHENING: The involvement of stakeholders like officers from the Erosion and Flooding Division of the Ministry of Environment and the Institute for Oceanography, in the design and implementation of this project has proved beneficial. Increasing knowledge of the appropriate protective measure to adopt in similar situations would benefit the nation on the whole.
SUSTAINABILITY: How sustainable this protective measure is, is debatable. A classic example of this phenomenon is documented along the Victoria Beach in Lagos. The construction of the two stone moles (east and west moles) between 1904 and 1912 sparked off a high rate of erosion on the downdrift side of the east mole, causing high rates of erosion on the Victoria Beach. What obviously comes to mind is that the remedial actions taken to protect the college would spark off other problems of erosion on the downdrift side. Would it be wise therefore to continue to protect the remaining 800 km of the Nigerian coast from erosion by constructing breakwaters or groynes or, do we have to seek a more sustainable way of protecting our beach ?
TRANSFERABILITY: The technology of using groynes to protect the Victoria Beach for example, could be transferred to other parts of the Nigerian coast with similar topography. However, the cost implications make this practice rare.
CONSENSUS BUILDING: The wp has been beneficial in protecting the foundations of the college from eroding. The government and the recipient Institution are also satisfied with the result. However, there is need to modify this methodology to accommodate the downdrift side, and also ensure that the project becomes a wp.
PARTICIPATORY PROCESS: The design and implementation process of this project was achieved with maximum participation from the Government and other stakeholders. However, the public has to be educated about the need to stop sand mining on the beach. Un-wise practices such as sand mining exacerbate the problem of erosion on the Victoria Beach.
EFFECTIVE AND EFFICIENT COMMUNICATION PROCESS: During the design phase there was communication between the project implementers and the stakeholders. Those implementing the project were totally responsible for financing the project. The stakeholders had not much choice but to accept the project.
CULTURALLY RESPECTFUL: Coastal lands belong to the Federal Government of Nigeria, hence by their approval of the project other state stakeholders had no objections.
GENDER AND SENSITIVITY ISSUES: Serious considerations are given to gender involvement in the project implementation and staff recruitment.
DOCUMENTATION: The design, methodology, implementation and monitoring of the project, is documented in the annual report of the monitoring team.
EVALUATION: This wp of protective groynes and breakwaters has proved partially sound in protecting the endangered property of the college, however, the transference of the problem to the downdrift side has to be given serious consideration. There should also be legislation to stop future sand mining on the beach.
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