Analysing the performance of multi-functional artificial reefs. Journal of Integrated Coastal Zone Management, 10(1), 127-145 (full text in Portuguese, extended abstract in English).

Authors: Simioni, B. and Esteves, L.S.

Editors: do Carmo, J.A., Dias, J.A. and Polette, M.

Journal: Journal of Integrated Coastal Zone Management

Volume: 10

Issue: 1

Pages: 127-145

ISSN: 1646-8872

DOI: 10.5894/rgci165

Abstract:

It is frequently claimed that artificial surfing reefs (ASRs) provide coastal defence, improvement of biodiversity, enhancement of surfing and boosting the local economy related to water sports and tourism. Although such functionality may have resonance in integrated coastal management (ICZM), the main public appeal is related to its effects on surfing. ASRs are a relatively new concept (the first was built in 1999) and available references mostly comprise technical reports and articles with no peer review. Further, the majority are authored by professionals involved with the development and commercialization of ASRs. With an increasing interest in the development of new ASRs (e.g. São Pedro do Estoril, Portugal), it is now important that objective and independent studies are undertaken to analyse the performance of ASRs for surfing enhancement and for the other benefits claimed. This study evaluates the effects of the six existing artificial reef projects (four of them built and two in construction process) on the quality of waves for surfing, coastal protection, biodiversity and tourism. Moreover, the implementation processes for ASRs are analysed taking into consideration the principles of ICZM. The sources of information used include the relevant existing literature and a range of other sources which allow assessment of public opinion (e.g. internet discussion boards, online local newspapers, websites about surfing etc.). The findings demonstrate that only a few independent monitoring studies have quantified the ASR performance objectively. The results reveal that ASRs have variable performances both for coastal protection and improving surfing waves. More than three years of monitoring of the shoreline response adjacent to the Narrowneck reef in Australia indicates that the beach width has increased. However, this may all be attributed to local beach nourishment. Surfer’s perceptions are mixed and generally express negative views regarding the reefs’ performance. Studies quantifying the enhancement of biodiversity or the economic revenue attributable to the reef are very limited or absent. Only one study have addressed the issue of biodiversity enhancement, and suggested that the Narrowneck reef might have helped improving the local productivity. However, the reef still had lower biodiversity than adjacent natural reefs. Even though implementation processes have been variable among the projects, there are several common elements: reefs have been built with the main aim of surfing improvement; public involvement in the decision-making process is absent or limited to consultation at late stages in the process; feasibility and cost-benefits analysis are produced by the developers; environmental impact assessments are not widely available if at all; final budgets surpass initial estimate of costs; and there are no independent studies to assess the financial benefits accruing from ASRs. This paper therefore suggests that it is now a priority to establish protocols to: (a) regulating the implementation of ASRs; and (b) define standards for monitoring studies pre- and post-reef construction (preferably conducted independently) with the objective of quantifying its environmental and socio-economic impacts.

http://www.aprh.pt/rgci/rgci165.html

Source: Manual

Preferred by: Luciana Esteves