MINISTRY OF FOREIGN AFFAIRS, TRADES, TOURISM, ENVIRONMENT AND LABOUR THE GOVERNMENT OF TUVALU
THE PROJECT FOR PILOT GRAVEL BEACH NOURISHMENT AGAINST COASTAL DISASTER ON FONGAFALE ISLAND IN TUVALU
FINAL REPORT (SUMMARY)
April 2018
JAPAN INTERNATIONAL COOPERATION AGENCY
NIPPON KOEI CO., LTD. FUTABA INC. GE JR 18-057 MINISTRY OF FOREIGN AFFAIRS, TRADES, TOURISM, ENVIRONMENT AND LABOUR THE GOVERNMENT OF TUVALU
THE PROJECT FOR PILOT GRAVEL BEACH NOURISHMENT AGAINST COASTAL DISASTER ON FONGAFALE ISLAND IN TUVALU
FINAL REPORT (SUMMARY)
April 2018
JAPAN INTERNATIONAL COOPERATION AGENCY
NIPPON KOEI CO., LTD. FUTABA INC. ● Project Overview in Photos(1/3)
Beach Condition after Construction
Fongafale Island
Before After
Before
After ● Project Overview in Photos(2/3)
Construction and Effect of Beach Nourishment 1. Protection Function (Wave condition during cyclone) Construction Workflow 1：Collection, Transport and Placement of Gravel Overview
＜Location Map＞
Borrow Pit (Sand collection) ▲ Outside of Project Site ▲ Gravel Collection at Tips of Islands ▲ Placement of Gravel at Project Site
▲ Project Site Workflow 3 Workflow 2：Construction of Groins at Project Site 2. Improvement on Beach Use
Project Site
Workflow 2
Workflow 1
▲ Placement of Core Stones from Fiji ▲ Placement of Armor Rock from Fiji ▲ Playing on Beach
▲ Fishing from Groin
Tips of Islands Workflow 3：Collection, Transport and Placement of Sand (Gravel Collection) 3. Improvement of Beach Environment
0 5 km
▲ Collection of Sand from Borrow Pit ▲ Placement of sand at Project Site ▲ Improvement of Scenery ▲ Habitat of young fish ● Project Overview in Photos(3/3)
Public Relations and Environment Education for Beach Management and Maintenance Changes in Public Awareness Beach Cleaning Event (before Construction) A Sequence Event including Beach Sports Festival
1. Environment Education
Changes in Activities Beach Song Competition 2. Beach Cleaning Event
▲ Voluntary Beach Cleaning Beach Tour during Construction 3. Beach Sports Festival
▲ Propagation of new ways of beach use - Preface -
Coastal problems such as coastal erosion, wave overtopping, storm surge, etc., are now serious in Tuvalu and other Pacific Island countries. Furthermore, the risk on coastal disaster will be increased by high waves and the rising of seawater level due to the impact of climate change. Each Pacific Island countries are undertaking coastal protection measures for disaster prevention and adaptation for climate change with worldwide support.
The coastal projects which were implemented in the Pacific Island countries were commonly just based on the “hard point of view”, which was just to consider the selection and implementation of hard structure measures. On the other hand, “soft point of view”, such as historical forming of original beach and island, original functions of the beach especially for beach use, relation of the beach to human life, culture and daily activities, etc., was not considered sufficiently. As a result, there were several cases that the implemented projects for coastal protection intercepted the beach from human life and activities, and induced indifference of people toward the beach.
Beach is closely related to the daily lives of the residents, giving the people various benefits and contributions. Beach is also the habitat for marine and coastal biota. Therefore, beach is required to be protected in order to maintain its function in nature. Also, historical records show that the beach is maintained and conserved by the community and residents who lived in close proximity to the beach. Keeping such relations between the beach and the people can achieve a healthy development of community with keeping nature and environment, and increase their emotional attachment to the beach.
Fongafale Island, which is the capital island in Tuvalu, has owned the degradation of coastal condition at the lagoon side due to alternation of foreshore area by U.S. Army during the Second World War and rapid concentration of the population in the last 20 years. Especially, disappearing of sandy beach and collapse of seawall made by concrete or concrete blocks led the increase of coastal disaster such as wave overtopping and storm surge, and interfered on beach use to the peoples. As the result, beach was drastically changed from that in original condition. Plenty of garbage left on the beach with bad smell before the Project.
Based on the above mentioned deteriorated condition of the beach, JICA was previously conducted two technical cooperation projects from both short-term and long-term points of view on coastal conservation, which were “The Study for Assessment of Ecosystem, Coastal Erosion and Protection/Rehabilitation of Damaged Area in Tuvalu” from 2009 to 2011 as the feasibility study to recover the beach with original image, and the science and technology cooperation project, titled “Eco-Technology Management of Tuvalu against Sea Level Rise” from 2009 to 2014 for the purpose to examine the mechanism of forming and maintaining of the island and to propose the eco-system coastal conservation measures taking into account the production, transportation and accumulation of coral sand. Based on the outcomes from each project, the Project was requested as technical cooperation project to propose to implement the short-term coastal conservation measures using a beach nourishment.
The Project of beach nourishment as the pilot scale coastal conservation measures was implemented from 2012 to 2018 in order to perform the “Ecosystem-based” and “user-friendly” type of coastal conservation measure, and to establish the community-based beach management in Tuvalu with sustainability. The propose beach nourishment is to recover the natural image of the beach, replacing the hard structure measures that were commonly applied in Tuvalu and other Pacific Island countries. The Project phase was divided into the following three phases. Phase-1: Planning and design (Mar. 2012 to Mar. 2013) Phase-2: Construction (Feb. 2015 to Dec. 2015) Phase-3: Monitoring, evaluation and beach management (Jan. 2016 to Jan. 2018)
In phase-1, the technical study based on field observation, data collection and numerical approach was conducted as basic study to examine the formation of the island, littoral movement for coral gravel and sand, and to prepare the planning and design of the beach nourishment to fulfil three functions, which are “protection”, “beach use”, and “environment”. As the coral gravel and sand, which were produced at Funafuti Atoll in Tuvalu, were employed as nourishment materials, the environmental impact to the extracted area of gravel and sand was also highly taken in account. The beach will be utilized as a public beach that the local people will commonly use, the public opinion about the Project was to be highly considered into the planning and design of the beach nourishment by organizing several public consultations, regardless of age and gender.
Although the issue about the design of beach width were exposed between JICA and the Tuvalu Government, it was solved on Nov. 2014. After that, the review of detailed design which was prepared in Phase-1 was re-examined and the construction was commenced on June 2015 and completed on Dec. 2015 as Phase-2.
The beach monitoring was carried out for two years in Phase-3 to evaluate the validity and effectiveness of the nourished beach. As the result, it was observed that the discharge of filled sand and gravel was quite small and the implemented beach could keep the stable condition.
To promote the realization of beach maintenance and management by the community and locals who were the main beach users, which is called “community-based beach management”, several PR (Public Relation) and educational activities were proposed and undertaken through each phase of the Project. One of successful activities was the beach sports events which were undertaken twice in 2016 and in 2017 of Phase-3. They could realize the fun and the contribution of the beach through the activities from the event. They also realized the importance to have responsibility for maintaining the beach through the beach maintenance work being taught in school educational programs and education classes. According to the obtained results of the interview survey with the locals, it was proven that the understanding of beach nourishment and the public awareness on beach conservation and maintenance were surely enhanced by the promotional PR and education programs. As a result, the community-based beach maintenance and management has been continued even though more than two years have passed from the completion of the construction.
The Project was the first trial to employ the beach nourishment method as the “Ecosystem-based” and “user-friendly” coastal conservation measures, and the community-based beach management in Pacific Island countries. So that, the knowledge transfer for the Project was actively conducted not only to Tuvalu but also to other Pacific Island countries by promoting several seminars and opportunities for technical exchange (presentation in GEF workshop in Tonga, technical exchange in Mauritius, participation to the international conference, etc.). Also, the leaflet, guideline etc. for the nourishment was prepared, and put on the Web site and distributed to related agencies at both inner and outer countries
We hope the outcome of the Project will contribute to the people of Tuvalu and other Pacific Island countries who are facing similar coastal problems and also to enhance their understanding of beach nourishment and the awareness on coastal conservation and its maintenance. Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Table of Contents
Project Overview in Photos
Preface
Executive Summary ...... ES-1
Part 1: Basic Study, Planning and Design
1. Introduction ...... 1-1 1.1 Background...... 1-1 1.2 Pre-understanding the Conditions before Commencement of the Project ...... 1-1 1.3 Objectives of the Project ...... 1-3 1.4 Project Area ...... 1-4 1.5 Scope of Work and Implementation Schedule ...... 1-4
2. Natural and Social Condition ...... 2-1 2.1 Natural Conditions ...... 2-1 2.2 Land Ownership and Law ...... 2-4
3. Field Survey, Data Collection, and Analysis ...... 3-1 3.1 Overview ...... 3-1 3.2 Sounding ...... 3-1 3.3 Profile Survey and Sand Sampling ...... 3-1 3.4 Coastal Situation of Construction Site...... 3-2 3.5 Coastal Situation of Planned Gravel Extraction Site ...... 3-2
4. Quality and Quantity of Materials for the Beach Nourishment ...... 4-1 4.1 Gravels ...... 4-1 4.2 Sand ...... 4-2
5. Planning and Design of the Beach Nourishment ...... 5-1 5.1 Conservation Target ...... 5-1 5.2 Design of the Beach Nourishment ...... 5-1 5.3 Quantity Calculation ...... 5-5
6. Project Implementation Plan ...... 6-1 6.1 Construction Planning ...... 6-1 6.2 Implementation Schedule ...... 6-4
7. Environmental and Social Considerations ...... 7-1 7.1 Overview ...... 7-1
i Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
7.2 Outline of Tuvalu’s EIA Regulation ...... 7-1 7.3 Scope of PEAR ...... 7-2 7.4 Conclusion ...... 7-2
8. Public Consultation and Project Coordination Committee (PCC) ...... 8-1 8.1 Overview ...... 8-1 8.2 Stakeholders of Public Consultation and PCC ...... 8-2 8.3 Results from Public Consultation and PCC ...... 8-3
Part 2: Construction and Monitoring
9. Construction ...... 9-1 9.1 Summary of Construction Work ...... 9-1 9.2 Effects of the Construction of the Beach Nourishment ...... 9-4
10. Monitoring Plan ...... 10-1 10.1 Overview ...... 10-1
11. Monitoring Result ...... 11-1 11.1 Coastal Hydraulic Condition ...... 11-1 11.2 Beach Change at Project Site...... 11-1 11.3 Beach Change at Reclamation Area ...... 11-7 11.4 Beach Change at Gravel Extraction Site ...... 11-8 11.5 Summary of Beach Monitoring ...... 11-11 11.6 Marine Environment ...... 11-11
Part 3: Beach Management and Maintenance in Post Construction Stage
12. Beach Management and Maintenance ...... 12-1 12.1 Structure and Overview ...... 12-1 12.2 Community-based Beach Maintenance ...... 12-2 12.3 Proposal and Practice for Sustainable Beach Management ...... 12-3
13. Adaptive Measure ...... 13-1 13.1 Overview ...... 13-1 13.2 Summary of Beach Change for 1.3 Years after Construction ...... 13-1 13.3 Proposed Adaptive Measure ...... 13-2 13.4 Implementation ...... 13-4 13.5 Obtained Effect ...... 13-6 13.6 Subject ...... 13-7
14. Public Relations (PR) and Educational Activities ...... 14-1 14.1 Overview ...... 14-1 14.2 Setting of Performance Goals ...... 14-1
ii Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
14.3 Implementation of Public Relations and Educational Activities ...... 14-2 14.4 Effects Confirmed by the Interview Survey and Observation ...... 14-5
Part 4: Capacity Development, Knowledge Transfer/Future Development of Beach Nourishment Project
15. Capacity Development and Knowledge Transfer ...... 15-1
16. Technical Guideline ...... 16-1 16.1 Overview ...... 16-1 16.2 Basic Policy ...... 16-1 16.3 Table of Contents ...... 16-2
17. Future Development of Beach Nourishment Project ...... 17-1 17.1 Overview ...... 17-1 17.2 Level of Understanding for Nourishment Based on Interview Survey ...... 17-1 17.3 Feasibility for Procurement of Nourishment Material ...... 17-1 17.4 Possibility for Implementation of Beach Nourishment Project in Tuvalu ...... 17-3 17.5 Subject and Consideration Point...... 17-5
18. Conclusion and Suggestion ...... 18-1 18.1 Conclusion ...... 18-1 18.2 Suggestion ...... 18-2
iii Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
List of Figures
Figure 1.1 Project Area ...... 1-4 Figure 1.2 Main Activities and Work Sequence of the Project ...... 1-5 Figure 2.1 Bathymetric Map of Funafuti Atoll ...... 2-3 Figure 2.2 Boundaries of Land just behind the Project Area ...... 2-4 Figure 3.1 Contour Map Surrounding the Project Area ...... 3-1 Figure 3.2 Coastal Situation of Planned Gravel Extraction Site (Funamanu Island) ...... 3-3 Figure 3.3 Coastal Situation of Planned Gravel Extraction Site (Papaelise Island) ...... 3-3 Figure 4.1 Criteria for Selection of Borrow Site for Gravels ...... 4-1 Figure 4.2 Location Map of Borrow Pits ...... 4-4 Figure 5.1 Final Layout Design ...... 5-2 Figure 5.2 Final Profile Design ...... 5-3 Figure 5.3 Final Design of the Groin (e.g., North) ...... 5-4 Figure 5.4 Final Design of Backshore Armor Stone...... 5-5 Figure 6.1 Location of Mining Gravel ...... 6-2 Figure 7.1 Main Flow of the EIA Approval Procedure ...... 7-1 Figure 8.1 Implementation Flow of the Public Consultation and PCC ...... 8-1 Figure 8.2 Stakeholders of Public Consultation and PCC ...... 8-2 Figure 9.1 Construction Photos ...... 9-3 Figure 9.2 Comparison of Wave Condition Before and After the Implementation (in high wave condition) ...... 9-5 Figure 9.3 Beach Use at the Shallow Water and Sandy Area ...... 9-5 Figure 9.4 Use of Constructed Coastal Facilities ...... 9-6 Figure 9.5 Fishes in the North Groin ...... 9-6 Figure 9.6 Comparison of Coastal Landscape ...... 9-7 Figure 10.1 Schedule for Each Monitoring Items ...... 10-3 Figure 11.1 Location Map of Profile Survey and Fixed Point Photography Position ...... 11-2 Figure 11.2 Comparison of Photos from Representative Two Fixed point ...... 11-3 Figure 11.3 Comparison of Beach Profile for 1.3 years (Before Conducting Adaptive Measure) ...... 11-4 Figure 11.4 Comparison of Beach Profile (Before and After Conducting Adaptive Measure and Just After the Construction) ...... 11-4 Figure 11.5 Image of Gravel Movement ...... 11-5 Figure 11.6 Change in Volume at Backshore Gravel Section (left: quantity, right: rate) ...... 11-5 Figure 11.7 Change in Volume at Foreshore Sand Section (left: quantity, right: rate) ...... 11-6 Figure 11.8 Change in Total Volume (left: quantity, right: rate) ...... 11-6 Figure 11.9 Shoreline Change Before the Construction of Groin ...... 11-8 Figure 11.10 Shoreline Change After the Construction of Groin ...... 11-8 Figure 11.11 Change in Beach Condition at Reclamation Area ...... 11-8 Figure 11.12 Location of Beach Monitoring at Funamanu Island...... 11-9
iv Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Figure 11.13 Location of Beach Monitoring at Papaelise Island ...... 11-9 Figure 11.14 Change in Beach Profile at East Tip of Funamanu Island ...... 11-10 Figure 11.15 Change in Beach Profile at West Tip of Funamanu Island ...... 11-10 Figure 11.16 Change in Beach Profile at West Tip of Papaelise Island ...... 11-10 Figure 11.17 Condition of Water Transparency in Post Construction Stage ...... 11-11 Figure 11.18 Condition of Existing Natural Corals (already died) ...... 11-12 Figure 11.19 Forming of New Fish Habitat ...... 11-12 Figure 11.20 Condition of Transplanted Coral ...... 11-13 Figure 12.1 Structure of Beach Management ...... 12-1 Figure 12.2 Beach Cleaning Event Involving Kaupule and the Residents ...... 12-2 Figure 12.3 Beach Cleaning by Kaupule and the Residents ...... 12-3 Figure 12.4 Proposed Sustainable Beach Management Structure ...... 12-4 Figure 13.1 Change in Beach Condition in the North Area ...... 13-1 Figure 13.2 Change in Beach Condition in the South Area ...... 13-2 Figure 13.3 Beach Behavior after Nourishment ...... 13-2 Figure 13.4 Proposed Adaptive Masure ...... 13-3 Figure 13.5 Area for Sand Refill (North Area) ...... 13-3 Figure 13.6 Example of Time Schedule for Adaptive Measure...... 13-4 Figure 13.7 Removal and Dumping of Gravel by Excavator (Step 1) ...... 13-5 Figure 13.8 Removal of Remaining Gravel Manually (Step 2) ...... 13-5 Figure 13.9 Transportation and Refill of Sand (Step 3) ...... 13-6 Figure 13.10 Comparison of Beach Condition Before and After the Work...... 13-6 Figure 14.1 Sequence of PR and Educational Activities Related to Beach Sports Festival ...... 14-4 Figure 14.2 Changes in Peoples’ Awareness on Beach through the Project Period ...... 14-5 Figure 14.3 Periodic Beach Cleaning by Community ...... 14-6 Figure 14.4 New Types of Beach Use Spread to the Community ...... 14-6 Figure 17.1 Existing and Potential Area for Beach Nourishment Project ...... 17-4
v Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
List of Tables
Table 1.1 Implemented Schedule ...... 1-6 Table 3.1 Points for Slope Measurement and Sand Sampling ...... 3-2 Table 4.1 Comparison Table for Overall Evaluation ...... 4-3 Table 4.2 Situations of Sand Thrown Into Borrow Pits ...... 4-3 Table 5.1 Design Tide Condition ...... 5-1 Table 5.2 Design Offshore Waves ...... 5-2 Table 5.3 Design Wave Condition for Structure ...... 5-2 Table 5.4 Comparison for Summary of Quantity ...... 5-5 Table 6.1 List of Construction Materials ...... 6-1 Table 6.2 List of Labor ...... 6-1 Table 6.3 List of Construction Equipment ...... 6-1 Table 6.4 Construction Schedule ...... 6-4 Table 6.5 Implementation Schedule (Pilot Construction and Monitoring) ...... 6-4 Table 9.1 Construction Process Sheet (Master Schedule and Actual) ...... 9-1 Table 9.2 Main Work Item and Quantity ...... 9-1 Table 9.3 Estimated and Actual Quantities ...... 9-2 Table 10.1 Items and Method of Monitoring for Hydraulic Condition...... 10-1 Table 10.2 Items and Method of Monitoring for Beach Change at and surrounding the Project Site ...... 10-1 Table 10.3 Items and Method of Monitoring for Beach Change at Gravel Borrow Site ...... 10-2 Table 10.4 Items and Method of Marine Environment ...... 10-2 Table 14.1 PR Activities of Pre- and During- Construction (2015) ...... 14-2 Table 15.1 Programs Implemented for Capacity Development and Knowledge Transfer...... 15-1 Table 17.1 Ideal Implementation Schedule for Beach Nourishment Project ...... 17-5
vi Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Abbreviations
Abbreviation Long Form
APAC International Conference on the Asian and Pacific Coasts
C/P Counterpart
DOE Department of Environment
DOF Department of Fisheries
DOLS Department of Land and Survey
EIA Environmental Impact Assessment
GEF Global Environment Facility
JICA Japan International Cooperation Agency
MET Tuvalu Metrological Service
NZ New Zealand
MFATTEL Ministry of Foreign Affairs, Trade, Tourism, Environment and Labour
NGO Non-Governmental Organization
PCC Program Coordination Committee
PEAR Preliminary Environmental Assessment Report
PR Public Relation
PWD Public Works Department
SGP Small Grants Programme
SOPAC South Pacific Applied Geoscience Commission
TCAP Tuvalu Climate Adaptation Project the beach Beach nourishment using coral gravel and sand implemented in this nourishment Project Project for Pilot Gravel Beach Nourishment against Coastal Disaster on the Project Fongafale Island in Tuvalu
vii Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Executive Summary
The outline and obtained results through the Project are summarized below.
Planning and Design
Necessity of coastal adaptation in Tuvalu
Tuvalu consists of small atoll islands with a low elevation of 2 m above mean sea level; however, the present coast of Tuvalu is being threatened by coastal disaster caused by high storm waves due to cyclone or atmospheric depression especially during high tide. The impact of climate change will cause further increase of risk on coastal disaster, and therefore, urgent coastal adaptation is strongly requested.
Typical coastal measure in Tuvalu
Hard structure measures using coral rock, poor concrete block, and concrete seawall have been employed in Tuvalu until now as common coastal protection measures. However, such protection measures were not only less effective on protection function, but also cause further deterioration of coastal condition for beach use and environment.
Concept of coastal adaptation
The objective area of the Project is located at the central area (Tausa Lima) on the lagoon coast of Fongafale Island, where the residential and public facilities and places exist. It considers three functions on the selection of coastal adaptation measures, which are “protection function”, “beach use”, and “coastal environment”. Maintaining the natural landscape the same image as the original natural beach was also taken into account in the design of the beach.
Proposed coastal adaptation measure
To improve the deteriorated coastal condition due to anthropogenic land alteration and collapse of previous protection measures, the beach nourishment using coral gravel and sand was proposed as first trial of ecosystem-based and user-friendly type of coastal adaptation measure.
Consideration on public consultation and consensus building
As constructed beach will be utilized as public beach, public opinion was highly considered to put into the design of the beach nourishment. Furthermore, Tuvalu had unique social condition on the organization of community and land ownership. Therefore, public consultation and consensus building were frequently organized and implemented with a consideration of balancing factors such as gender and age throughout the Project duration.
ES-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Basic concept of beach profile design
The beach profile design, such as beach slope and berm height, basically follows the same condition of the existing natural beach considering the stability against wave action. As a result, the berm height was set at +4 m and the beach slope for gravel and sand was set at 1:3.5 and 1:11 respectively, to keep the consistency with the existing natural beach.
Discussion for design of beach width
The design of beach width was hardly discussed with the Tuvaluan government. Even though the Tuvaluan government requested to widen the beach width as much as possible to create new land space, the measurement was finally decided at 6 m for the backshore width and approximately 20 m for the average width of the beach in the mean sea level (MSL) condition considering the purpose of the Project and maintaining the stability to the beach.
Concept of layout design
Based on the request from the Tuvaluan side, the location of the Project site was selected in Tausoa Lima on the lagoon side of Fongafale Island as the most attractive public area. The alongshore distance was set at 177 m considering the existence of deep water area at the north and private seawall in the south. To minimize the expected future discharge of filled gravel and sand, the armor rock type groins were set at each side of nourishment area. The following considerations were taken into account in the design of groins and determined each dimension: 1) function in maintaining the nourished material, 2) impact on beach use and accessibility in alongshore direction, 3) harmony with natural landscaping, and 4) to minimize the quantity of material.
Procurement of construction material
Coral gravel and sand procured in Tuvalu were applied as the beach nourishment material to show the sustainability for future coastal adaptation in Tuvalu with their ownership. Armor rock for groin was imported from Fiji and Taveuni Island.
Special consideration on environmental impact for procurement of gravel
Environmental impact, especially impact to surrounding coast, was highly taken into account for the procurement of gravel in Tuvalu. The mechanism for gravel accumulation and movement due to wave action at the ocean side of Funafuti Atoll was examined based on the historical shoreline change by satellite image analysis. Taking into account the required quantity of gravel, impact to existing live corals during the construction work, and the construction cost as pilot-scale project as well as impact to surrounding coast, it was decided to extract the gravel from the tip of Funamanu and Papa Elise islands, which were accumulated by the effect of Cyclone Bebe in 1972.
ES-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Construction
Bidding and construction schedule
After the bid process conducted in the Japan International Cooperation Agency (JICA) Fiji Office from April to June 2015, the construction work commenced on 15 June 2015 by the contractor in Fiji (Cruz Holding JV) and was completed on 23 December 2015, about six months without any delay from the contracted period.
Construction item and quantity
Main construction items were 1) collection and transportation of gravel from the islands, 2) groin construction, 3) gravel nourishment, 4) sand nourishment, and 5) installation of backshore stone. About 3,300 m3 for gravel and 4,500 m3 for sand were filled into the Project area with a 177 m alongshore distance.
Environmental consideration during construction
The monitoring of marine environment and water quality was carried out at both the gravel taking and the construction sites through the construction period. The water quality (turbidity) and the condition of existing corals and marine life were monitored frequently during and post construction period. The results show that there were no significant environmental impacts at both the gravel taking and construction sites due to the construction activities
Social consideration during construction
During the construction work, consensus building and several public relation (PR) and educational activities such as beach cleaning event and beach tour for primary school students were actively conducted to enhance public awareness and understanding on beach conservation.
Effect of the constructed beach
After the construction of the beach, it was confirmed that the expected three functions were sufficiently emerged and these functions were well recognized and evaluated by the residents. The three functions were summarized as 1) protection against high wave, 2) improvement on beach use, and 3) improvement on beach environment and scenery.
Monitoring
Monitoring items
Beach monitoring at both the Project site and gravel borrow sites was continuously carried out for almost two years. The objectives of the monitoring are 1) to check the stability of the nourished beach, 2) to check the impact to the surrounding coast at both the Project site and borrow site, and 3) to examine the required adaptive measures. The
ES-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
main items of the beach monitoring were 1) taking photos from fixed points, 2) beach profile survey, 3) taking bird’s-eye view photos using a drone, 4) wave and tide observation, and 5) interview survey.
Monitoring results
1) The Project beach could maintain the stable condition even though it was struck by high waves during the approaching cyclone. The discharge rate for combined gravel and sand was about 3% for two years.
2) Sand, which was filled in the foreshore section, has a tendency to shift to the south in total due to littoral drift, and a part of the shifted sand that overflowed to the south beach. Also, a part of the fine contents of sand can possibly be moved to the offshore side. Total discharge rate for sand was estimated to be about 5% for two years.
3) A part of the gravel, which was filled to the backshore section, were moved to the foreshore sandy part and were scattered by continuous wave action. Due to this, the crest line of gravel section had a little retreat with approximately 1 m in average and 3 m at maximum in the north part of the Project area. However, gravel was just moved from the backshore to the foreshore side and no discharge of gravel to the outer area was observed.
4) No change in the beach slope from the initial situation just after the construction was observed at both the gravel and sand sections. This proves that the design slope was appropriate.
5) The Project beach was highly utilized by the local people for swimming, recreation and rest space, and fishing, while boat landing is also expected. Beach environment was also improved drastically based on the result of the interview survey and visual checking on site. Significant increase in the number of baby fish and crustaceans and improvement of water transparency were observed.
6) No negative impact to the surrounding coast was identified both at the Project site and the gravel borrow site in Funamanu and Papa Elise islands.
Maintenance and Management
Necessity of community-based management
The Project beach is utilized as a public beach for the Funafuti people, who are the main users of the beach and therefore have frequent opportunities to identify the current beach condition. From this, it was realized that not the “government-based beach management” but the “community-based beach management” was necessary to maintain the beach.
ES-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Activity for beach maintenance
Community-based beach maintenance was carried out mainly by the Funafuti Kaupule while keeping their passion and motivation during the post construction stage. The Project beach could be kept clean due to weekly or bi-weekly routine cleaning activities.
Application of adaptive management system
Adaptive management system to the nourishment based on a PDCA (Plan-Do-Check-Act) system, which is monitoring, evaluation, planning of adaptive measure, implementation, and re-monitoring, was proposed and was tried to carry out in September 2017 in the post construction stage to maintain the beach in good condition and enhance the life period of the beach.
Consideration of sustainability for adaptive measure
Proposed adaptive measure was highly considered to employ the “simple and easy method with only low technology” to be able to take action by only the Tuvaluan side after the completion of the Project. Furthermore, the “interactive activation structure”, which consists of “execution of adaptive measure”, “active use for events using improved beach”, and “educational activity”, was proposed to ensure the sustainable execution of community-based beach management by the Tuvaluan side.
Implementation of the proposed adaptive measure
Removal of gravel from the sandy foreshore area and throwing it into the original gravel backshore area were undertaken by the Funafuti Kaupule using an excavator and manually by the primary school students in 1.7 years after the completion of construction. Small quantity of sand with 80 m3 filled the north area to improve the beach condition at the foreshore sandy part.
Necessity of public relation (PR) and educational activities on beach management
Beach management is an activity to keep the beach area in good condition after the construction. At the beginning of the Project, there were a lot of rubbish accumulated on the beach, which showed people’s bad behavior and lack of interest on the beach. Furthermore, it was anticipated that even if the beach environment had been improved by the Project, it would go back to the same bad situation in the future. Therefore, it was considered that improving their awareness was essential for proper beach management in the future. PR and educational activities were applied to improve awareness on beach environment.
Contribution of PR and educational activities to the beach maintenance and management
Since changing public awareness was not an issue to be done in a short period, the following step-by-step approach was set as objectives for the PR and educational
ES-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
activities as follows: step-1) People become interested on the beach, step-2) People experience and understand the benefits from the beach, step-3) People begin to take concrete actions on beach management.
A variety of PR and educational activities were implemented to accomplish the objectives, for example, the beach cleaning event was implemented before the construction for the purpose of step-1) and the beach sports event was conducted twice (July 2016 and September 2017) for the purpose of step-2). According to the interview survey, improvement of public awareness on the beach was confirmed and consequently, community’s active participation on beach management such as on beach cleaning was observed as an outcome of the PR and educational activities.
Capacity Development, Expansion of Knowledge
Implemented program and activities for capacity development and expansion of knowledge.
The following several programs were implemented to enhance capacity development of stakeholders and expansion of knowledge of beach nourishment: 1) Technical exchange in Mauritius on management and maintenance of gravel beach, 2) Training in Japan on management of beach nourishment, 3) Seminar on the beach nourishment, 4) Training of measurement equipment for wave and current, beach profile, bird’s-eye view photos, 5) GEF ECW (Global Environment Facility Expanded Constituency Workshop), and 6) Presentation of technical papers in the International Conference on Asian and Pacific Coasts (APAC) in Philippines .
Preparation of Technical Guideline
The technical guideline for beach nourishment was prepared as one of the results of the Project. This guideline shows the basic idea for the consideration on selection of coastal adaptation measure and for planning and design of beach nourishment to expand the knowledge for ecosystem-based and under-friendly type of coastal adaptation measure.
Future Development of Beach Nourishment Project in Tuvalu
Understanding and demand for beach nourishment
Based on the result of the interview survey to the Tuvaluan people, they have well realized the advantage of the beach nourishment on beach use and coastal environment, and most of them really wanted the same type of measure as coastal adaptation measure in Tuvalu. They also realized the importance of taking action on beach maintenance through participation in sports event on the beach and other educational activities.
ES-6 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Potential for procurement of sand to full-scale project
Because of the existence of plenty of sand in the lagoon, there is basically no issue for securing sand in Tuvalu. However, attention should be given to the location of the borrow site taking into account the impact to the coast as well as the grain size of the nourishment material.
Potential for procurement of gravel to full-scale project
Two potentials to procure coral gravel are expected, which are taken from the deep channel at the south side of Funamanu Island and sorted gravel from the dredged seabed material on the lagoon. Further study is required to identify the potential volume for construction method and cost. In case that there is no feasibility to procure the gravel in Tuvalu, gravel might be imported from outer overseas countries as final selection.
ES-7 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
1. Introduction
1.1 Background
Tuvalu, composed of small atoll islands, is getting the attention of the entire world as the elevation of the country is almost less than 2 m above mean sea level. Hence, it is projected that the island is significantly susceptible to climate change effects, particularly the subsequent sea-level rise in the future. In the meantime, the present coast in Tuvalu is already threatened with coastal disaster caused by high tidal waves due to cyclone or atmospheric depression especially during high tide. It is also pointed out that coastal erosion could accelerate the risk because lesser areas are being protected by natural coasts. Some of the past studies revealed that the main causes of the coastal erosion were the anthropogenic land alteration and the increase in environmental load due to population growth.
Facing these threats under the present and future climate conditions, the Government of Tuvalu requested the Government of Japan in 2008 to conduct a comprehensive study towards strengthening the resilience of the coastal area. A coastal protection plan for Fongafale Island was recently established with substantial assistance from the Japan International Cooperation Agency (JICA) through the project titled “The Study for Assessment of Ecosystem, Coastal Erosion and Protection/ Rehabilitation of the Damaged Area in Tuvalu” from August 2009 to January 2011. Considering the environmental impacts and unique social customs of Tuvalu, JICA formulated the plan and proposed the beach nourishment using coral gravel and sand as a countermeasure to reduce the disaster risks associated with overtopping and inundation. However, a beach nourishment as one of the coastal protection measures has never been implemented in Tuvalu. In May 2011, the Government of Tuvalu requested the Government of Japan for assistance to examine the effectiveness and adequacy of the beach nourishment in Tuvalu.
1.2 Pre-understanding the Conditions before Commencement of the Project
(1) Conditions on the Countermeasures for Coastal Disaster
1) Fragility of the Existing Coastal Facilities and Problems in Coastal Land Use
Many coastal protection facilities have been constructed in Fongafale Island, either through public works or by individuals to prevent coastal erosion. Common protection measure before was just concrete seawall or vertical revetment using poor concrete block or coral rock. Such coastal protections didn’t have sufficient efficiency on protection function. Also, further deterioration on coastal use and environment was induced.
1-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
2) Insufficient Equipment for the Implementation of the Project
The Department of Public Works (PWD) owns the heavy equipment, such as backhoe, loader etc., which will be used for the coastal project。However, the number of such equipment was very limited and the condition of the equipment were also no good due to less maintenance. Therefore, it will not be possible to carry out the work with these equipment in accordance with the schedule.
3) Insufficient Human Resources and Capabilities of Government Organization Related to Coastal Project
Below are the notable causes of insufficient human resources and capabilities of government agencies and organization related to the coastal project.
Lack of budget and manpower on coastal protection and its maintenance work
Less understanding on coastal conservation including consideration of “protection function”, “coastal utilization” and “coastal environment”.
Lack of capability for understanding of coastal measures, coastal engineering and management.
4) Insufficient Capacity and Experience in EIA
The experience of staff in carrying out EIA was insufficient. Even though Tuvalu’s EIA guidelines were established in detail, it was inferred that a number of personnel in the Department of Environment have no virtual experience in evaluating a project using these guidelines.
(2) Condition of Regional and Social Structures in Fongafale Island
1) Unique Land Ownership System
In Tuvalu, it is only possible to transfer a land to a person if the person was born in the island, and this also applies whether by sale, gift, or lease. The current laws and regulations regarding land use appear to have been created based on the traditional form of land ownership in Tuvalu.
2) Relationship between Immigrants from Other Islands and Those Born on the Island
Of the total number of residents in Funafuti, Tuvalu’s capital, only a quarter are natives of the island while the rest are immigrants. Those who were born in other islands have no right to land ownership, so they are in a weaker position with respect to land ownership rights compared with those who were born in Funafuti. Consequently, those with no land ownership rights mainly lived in hazardous areas that are susceptible to disasters like coastal erosion and climate change. Many households could be seen situated in the gap between the edges of
1-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
borrow pits filled with trash and the outer ocean, so it is necessary to take into consideration these weakest members of the society.
3) Prohibition from Participation of Younger Generation and Women in Meetings
In community and island meetings that determine self-governance of the island, men younger than 50 years old as well as women have less opportunity to speak. They have almost no participation in decision-making during meetings of the Fale Kaupule, a house where chiefs make decisions.
(3) Pilot Project for Beach Nourishment using Coral Gravel and Sand
1) Alteration of Pilot Construction Site
The pilot construction site indicated in the specifications has been moved from the original proposed construction location in the completed JICA Development Survey to the south on the opposite side of the Catalina Ramp. The changed pilot construction location was in Malefatuga District. There is a community hole for Funafuti community and church in the hinterland and here are the most people gathering place in Fongafale Island.
2) Procurement of Gravel for Nourishment
In the completed JICA Development Survey, four potential possibilities were nominated as candidate borrow sources of gravel, which are a) Inside Funafuti Atoll, b) North side of runway, c) Imported from Fiji, and d) Sand spit at nearby island. However, it is necessary to re-examine the candidate of borrow sites taking into account the economic efficiency, environmental impact, characteristics as nourishment material, construction and sustainable development.
1.3 Objectives of the Project
The project will proceed on the basis of the “Record of Discussion on Project for Pilot Gravel Nourishment against Coastal Disaster on Fongafale Island in Tuvalu” as agreed upon between the Government of Tuvalu and JICA on November 16, 2011. The objectives of the project are as follows:
Objective 1 To examine the effectiveness and adequacy of the beach nourishment using coral gravel and sand
Objective 2 To reduce the vulnerability against natural disaster (including climate change risk)
1-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
1.4 Project Area
The project area is shown in Figure 1.1. The final recommended site was Malefatuga area.
Figure 1.1 Project Area
(Source: JICA Expert Team)
1.5 Scope of Work and Implementation Schedule
The project consists of three phases and the final main scope of work for each phase is as follows.
Phase-1: Review, Basic and Detailed Design Phase-2: Review of Phase-1 (due to suspension after the Phase-1), Construction Phase-3: Monitoring and Evaluation, Maintenance and Management, Technical Transfer and Capacity Development The main activities for each stage and the implemented schedule are shown in Figure 1.2 and Table 1.1.
1-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Figure 1.2 Main Activities and Work Sequence of the Project
(Source: JICA Expert Team)
1-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report 5 F/R 4 3 2018 2 5th - 1 II 12 DF/R 11 10 Sports 9 8 Beach Event (2nd) 7 in Tonga in GCF W/SGCF 6 2017 5 4 3 2 (Source JICA Expert Team) Seminar Seminar 1 12 11 & Management & 10 Transfer & Capacity Development Capacity & Transfer 9 8
Sports 7 6 2016 Monitoring Monitoring & Evaluation Maintenance Technical 5 Beach Event (1st) in Japanin Training 4 IT/R2 3 4th - II 2 of the Project the of 1
le 12 Monitoring 11 Exchange Completion Celemony 10 9 Mauritius 8 Technical in 7 3rd Construction - 6 II 2015 Preparation P/R W/S 5 Bid 4 2nd - 3 II of 2 1 1st - - Implemented Schedu Implemented
1 II 1 . Review Phase 1 1-12 2014 R/D Amended Suspended 4-12 Table Table 3 IT/R1 2013 2 2nd - I 1 12 & Detailed & W/S 11 Design 10 Basic 9 8 Seminar Seminar Study 7 6 2012 W/S 1st - Basic 5 I IC/R 4 3 Review 2 1 Review Phase Report Monitoring Basic Study Construction Development PCC, R/D PCC, Events, etc.Events, Review of Phase-1 of Review Basic &Detailed Design &Detailed Basic Monitoring &Monitoring Evaluation, Maintenance & Management, & Maintenance Technical Transfer & Capacity & Transfer Technical Seminor, W/S, Overseas Training 1 2 3
1-6 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
2. Natural and Social Condition
2.1 Natural Conditions
This Chapter mainly presents information of natural condition that were reviewed at the beginning phase of the Project in Phase-1 stage.
(1) Meteorological Conditions
1) Winds
Wind conditions in Fongafale Island differ in four seasons in the region, i.e., summer and wet season from December to February, winter and dry season from May to September, and two transit seasons from March to April and from October to November.
Annual winds are predominant from an easterly direction of east-northeast to southeast directions. Strong winds of more than 8 m/s are observed from a westerly direction of southwest to north.
During the summer season, northeasterly winds from north to east-northeast are predominant. Strong westerly winds reaching more than 12 m/s are also observed during this season.
During the winter season, southeasterly winds are predominant, but strong winds of more than 8 m/s are very rare cases.
2) Precipitations
Precipitation shows a seasonal change, which is typically divided into two seasons, rainy season from December to March and dry season from April to November.
3) Tropical Cyclones
Historical records show that there were three tropical cyclones which had a major impact on Tuvalu (formerly known as the Ellice Islands). Two were unnamed and occurred on February 18, 1891 and January 2, 1958. The other was Cyclone Bebe, which occurred in Funafuti on October 21, 1972 with the lowest recorded mean sea level pressure of 954 hPa, with a maximum 10-minute average wind speed of 80 knots and a maximum 3-second gust of about 110 knots. The storm surge was reported to be about 4 m above the mean high water level mark.
2-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(2) Oceanography
1) Sea Level
Based on the variation of maximum water level and average water level at Funafuti SEAFRAME Station for 17 years from 1995 to 2011, the average rate of sea level rise obtained was 4.4 mm/year.
2) Tide
The graph clearly shows that the type of tides in this area is a semidiurnal tide, which has two high waters and two low waters in a day, and the height of each successive high waters and low waters are almost equal. The tidal curves from February 27 to March 1, 2006 recorded the highest high water level of 3.415 m since installation at SEAFRAME Station in Funafuti.
3) Waves
a) Ocean Side Wave measurements with a waverider buoy were carried out off the eastern coast of Funafuti Atoll between May 8, 1990 and April 7, 1992 with sampling interval of every three hours.
Significant wave heights are almost constant, average significant wave height is 1.8 m, and average period is 9.2 s. Although wave climate is steady offshore, it is not necessarily the case on the coast due to the strong seasonal wind direction in this region. The maximum significant wave height is from 2.4 m to 3.4 m and the period is from 10.5 s to 14.2 s.
b) Lagoon Side According to wave observation during previous investigations from November 1 to 21, 2009, the significant wave height and period are between 0.2 m and 0.3 m, and between 2.0 s and 4.0 s, respectively. From February 2, 2010 to March 19,2010, the significant wave height and period are between 0.2 m to 1.4 m, and between 2.1 s to 4.5 s, respectively. The former is almost dry season and the latter is almost wet season.
(3) Geographical Conditions
1) Land Topography
Fongafale Islet is a long and narrow strip of extremely low elevation with a broad “V” shaped outline. Dead coral rubbles are piled up at the ocean-side fringe of the islet up to 3 m above mean sea level, making the highest point of the islet. Other areas below 2 m above mean sea level are in a large portion of the islet.
2) Coast Line
Senior residents remember that there was a long, low-gradient, sandy beach prior to WWII. Modifications of the lagoon side of Fongafale Islet during WWII include a 2.3 km long piece
2-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
of reclamation with coral rock seawall, a long borrow pit (often called channel) beside the seawall, and other channels normal or parallel to the seashore.
Observing the present state of the coastline along the lagoon side of the central part of Fongafale Islet, most of the beach is covered with rocks and sand that extends for about 500 m long from the north of Vaiaku Lagi Hotel (now Funafuti Lagoon Hotel) to the south of Catalina Ramp.
3) Bathymetric Features
a) Ocean Side The bathymetry in the Funafuti Atoll is shown in Figure The reef flat on the ocean side is about 100 m wide in front of a storm ridge. Outside of the reef edge, depth increases rapidly and is over 1000 m in depth.
b) Lagoon Side The lagoon side reef flat is 55 m to 350 m wide, including a 15 m to 25 m wide beach as shown in Figure 2.1. Inside of the lagoon, shallow places (Te Akaue) are scattered. The water depth in the central part of the lagoon ranges from 40 m to 50 m and the maximum depth can be read as 49 m on the existing chart (Funafuti Atoll, Chart No.83094).
Figure 2.1 Bathymetric Map of Funafuti Atoll (Source: SOPAC)
2-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
2.2 Land Ownership and Law
(1) Land Property and Ownership
The land use classification in Fongafale Island mainly consists of four types: 1) Private land, 2) Crown land, 3) Leased land to the Government of Tuvalu by private owner, and 4) communal lands owned by Funafuti Kaupule.
(2) Law for Coasal Area
The basic law for coastal area in Tuvalu is the “Foreshore and Reclamation Act (revised in 2008)”. According to the act, area of sea bed and foreshore are defined by boundaries of H.T.L.(Highest Tide Level) and L.T.L.(Lowest Tide Level). Ownership of sea bed and foreshore belong to the Government of Tuvalu, stated as “Crown Land” in the Act. On the other hand, inland area is originally owned by private owners with acquired right. Foreshore area is the Government property; however, the management and permit body is Funafuti Kaupule. The Project area is in the foreshore and sea bed area.
(3) Boundaries of Land behind the Project Area
Land behind the Project area consists of the private land and the communal land. There are five private lands of different owners just behind the Project area shown as No.1-No.5 in Figure 2.2 and the rest of it along coast is communal land owned by Funafuti Kaupule (No.6).
3 4 5 Tausoalima 1 2 community 6 hall
Ekalesia Kelisiano Church Figure 2.2 Boundaries of Land just behind the Project Area (Source: JICA Expert Team)
2-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
3. Field Survey, Data Collection, and Analysis
3.1 Overview
The following two surveys were carried out in this study to contribute to the planning and design of the beach nourishment at the Project site:
➢ Sounding at the Project site
➢ Sand sampling and sieve analysis
3.2 Sounding
Figure 3.1 shows the contour map surrounding the Project area, which was obtained in the previous study. Here, Area A is the new survey area in this study.
Figure 3.1 Contour Map Surrounding the Project Area (Source: JICA Expert Team)
3.3 Profile Survey and Sand Sampling
(1) Survey of the Existing Gravel Beaches to Determine Profiles and Grain Size
The backshore slope at gravel part is constant regardless of the difference in grain size of gravel. The backshore slope at the ocean side is about 1:3 to 1:4, and is steeper than that at lagoon side (1:4 to 1:5).
3-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(2) Elevation of Storm Ridge and Hinterland
The storm ridge at the lagoon side is distributed from elevation 3.6 m to 4.9 m, and 4.1 m on average. On the other hand, the storm ridge at the ocean side is distributed from elevation 4.3 m to 5.3 m, and 4.9 m on average.
(3) Sand Sampling and Checking Foreshore Sandy Slope
The relationship between foreshore slope and grain size of sand was examined by conducting sand sampling and survey of foreshore slope at the existing sandy beach. As sandy beaches are not limited in Fongafale Island, survey was carried out not only in said island but also in other islands where natural sandy beach exists. The points of slope measurements and sand sampling are shown in Table 3.1. Table 3.1 Points for Slope Measurement and Sand Sampling Location Foreshore Slope Grain Size (Sieve Analysis) South of the Project Site in 1:12 Undertaken in Fiji Fongafale Island Fualifeke Island 1:10 Undertaken in Fiji North of Amatuku Island 1:10 Undertaken in Fiji North of Fongafale Island 1:12 Undertaken in Fiji (Source: JICA Expert Team)
3.4 Coastal Situation of Construction Site
(1) Coastal Survey Result
The natural gravel and 30 cm square concrete blocks are scattered in the construction site. East side is relatively open, there is a meeting place, etc. On the other hand, the west side has lush cover the trees of palm, etc. to the coast, sand is deposited as west.
(2) Coastal Survey Result
The beach slope is about 1:5 at gravel, about 1:10 at sand. Sediment median particle size is 0.5 mm in the foreshore, 0.2 mm at the flat shore.
3.5 Coastal Situation of Planned Gravel Extraction Site
(1) Site Reconnaissance Result
Gravel, as shown in Figure 3.2 and Figure 3.3 are deposited to form berm with several width. White gravel shown in photo is the newly deposited portion, and becomes target for extraction.
3-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
West end East end Figure 3.2 Coastal Situation of Planned Gravel Extraction Site (Funamanu Island) (Source: JICA Expert Team)
Figure 3.3 Coastal Situation of Planned Gravel Extraction Site (Papaelise Island) (Source: JICA Expert Team)
(2) Coastal Survey Result
➢ East of Funamanu Island: The beach slope is about 1:3 to 1:4 except tip.
➢ West of Funamanu Island: The beach slope is about 1:3 except tip. Significant topographic change in the first phase is not observed except tip.
➢ West of Papaelice Island: The beach slope is about 1:3 same as Funamanu island.
3-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
4. Quality and Quantity of Materials for the Beach Nourishment
4.1 Gravel
(1) Overview
1) Procedure for Selection of Borrow Site for Gravel
Figure 4.1 shows the criteria employed in the selection of borrow site for gravel.
Figure 4.1 Criteria for Selection of Borrow Site for Gravel (Source: JICA Expert Team)
Four potential possibilities below were nominated as candidate borrow sources of gravel and evaluated mainly using criteria shown in Figure 4.1.
a) Inside Funafuti Atoll
b) North side of runway
c) Imported from Fiji
d) Sand spit at nearby island
(2) Summary and Evaluation Results for Gravel Borrow Site
The obtained results are summarized as follows:
➢ There are two feasible sources, namely, 1) imported from Fiji and 2) taking from nearby island at Funafuti Atoll.
➢ It was feasible to import the gravel from Fiji considering the potential volume and quantity. The treatment of fumigation is required when gravel materials are imported to Tuvalu. As a result of preliminary study based on previous technical papers and comments from authorized institutes in Japan, no negative impacts on coastal and marine
4-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
environment are expected. On the other hand, the most disadvantageous issue is the high cost as compared to taking gravel from nearby island. Furthermore, it is desirable to employ “self-produced materials in Tuvalu” as much as possible taking into account the sustainability and ownership in Tuvalu.
➢ The gravel materials have been washed away due to wave action at the ocean side in Funafuti Atoll, and significant deposition of gravel was observed at nearby islands. Based on the results related to the mechanism of gravel movement, westward gravel transportation is expected. Thus, it is recommended to take gravel from Funamanu Island and Papaelise Island only for the pilot construction, taking into account the required quantity and potential volume of gravel in said island.
➢ On the other hand, it was not allowed to extract significant quantity of gravel for future full-scale projects considering the possibility of beach erosion in the surrounding beach. However, it was found that certain amounts of gravel exist on the seabed at the channel which is located at west side of Funamanu Island. Even though further investigation is required, there is a possibility that this location will be a potential borrow site for gravel to be utilized for future full-scale project.
4.2 Sand
(1) Overview
As survey contents of sand for nourishment, the comparison study in terms of following items was carried out based on present condition, existing information and hearing survey about two cases such as case1): sand is dredged by the project as shown in Phase-1 and case 2): sand is supplied by NZ project. The comprehensive evaluation was conducted in regard to applicable sand supply method for nourishment. ➢ Place of sand extraction ➢ Method of sand extraction ➢ Quality of sand ➢ Schedule (Construction period) ➢ Transportation method ➢ Cost ➢ Employment and future development
(2) Overall evaluation
The comparison study is carried out as follows in terms of “sand supply by contractor of the project” and “procurement of sand from NZ Project” is shown in Table 4.1.
4-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Table 4.1 Comparison Table for Overall Evaluation Sand supply by contractor of the project Procurement of sand from NZ Project This case has various risks such as the large increase Various risks can be eliminated as compared with of construction cost, delay of construction period, the left case and the possibility of employment lack of ability of the contractor in Fiji for dreading opportunity and future development is higher work. In addition, the possibility of employment than left case. opportunity and future development is lower than There is a risk of extension of construction the right case. period if timing of sand filling to stockpile by NZ It is difficult to complete whole construction work project delays. But it is possible to rearrange within this year considering that completion period construction period. Therefore, the total risk is is limited (Marine work should be completed by the lower than the left case markedly. beginning of November) and the start of As a result, this case is strongly recommended. construction is after June at the earliest. As a result, this case is not recommended.
(Source: JICA Expert Team)
At first, in New Zealand Project, the dredging sand was planned to stock at Borrow Pit No.2 for the purpose of coastal maintenance and securing construction material in the future. Therefore this JICA Project planned to supply the sand used for the beach nourishment from here. But enough sand can't be secured offshore No.2, for which it was necessary to consider sand supply from other borrow pits too, and the characteristics of material thrown into these pits were investigated. The location of borrow pits is shown in Figure 4.2 and situations of sand thrown into borrow pits are shown in Table 4.2.
The average of each borrow pit is as follows: No.1 is the largest and 0.82 mm, then, 0.64 mm at No.4, 0.51 mm at No.2. However, the No.1 and No.4 which include a number of Halimeda, are not suitable as for the beach nourishment material. On the other hand, No.2 is considered to be most suitable for the beach nourishment, because No.2 contains a lot of foraminifera and hardly contains Halimeda. Therefore, the beach nourishment material was supplied from here by JICA Project. Table 4.2 Situations of Sand Thrown Into Borrow Pits
(Source: JICA Expert Team)
4-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Borrow Pit No.2
Borrow Pit No.3
Borrow Pit No.4
Borrow Pit No.6 Borrow Pit No.7 Borrow Pit No.8 Borrow Pit No.9 Borrow Pit No.10
Borrow Pit No.5 Borrow Pit No.1
Figure 4.2 Location Map of Borrow Pits (Source: JICA Expert Team)
4-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
5. Planning and Design of the Beach Nourishment
5.1 Conservation Target
The targets in terms of protection function, environment, and utilization were set for the planning and design of the beach nourishment.
Protection
➢ Wave run-up and wave overtopping into the land area and private property can be prevented.
➢ Further beach retreat due to beach erosion can be stopped.
Utilization
➢ The selected beach conservation measure should contribute to enhance the beach utilization, such as for recreation and boat landing activities.
➢ The selected beach conservation measure is expected to transform the beach into a model beach and the most attractive area in Funafuti community area.
Environment
➢ Undertaking the beach protection measures at the Project site should not cause any new beach erosion problems at the surrounding beaches.
➢ The implementation activity should not cause the deterioration of marine biota such as corals, fish, sea glass, etc.
➢ It should not cause new beach erosion problems at the borrow sites for gravel and sand.
5.2 Design of the Beach Nourishment
(1) Design Condition
1) Design Tide
The design tide condition is shown in Table 5.1. Table 5.1 Design Tide Condition H.H.W.L CDL +3.42 m H.W.L CDL +2.80 m M.W.L CDL +2.00 m L.W.L CDL +1.20 m (Source：Completed JICA Development Survey Report (2011))
5-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
2) Design Waves
The design waves for 30-year return period was adopted as design condition for permanent structure (i.e. groins) . The design offshore waves and design waves for structure are shown in Table 5. 2 and 5.3, respectively. Table 5.2 Design Offshore Waves
Return Period Wave Height (H0)1/3 (m) Wave Period T0 (s) 10 years 1.2 4.2 30 years 1.9 4.2 50 years 2.2 5.6 (Source：Completed JICA Development Survey Report (2011))
Table 5.3 Design Wave Condition for Structure
Return Period Wave Height H1/3 (m) Wave Period T1/3(s) 10 years 1.12 4.2 30 years 1.56 4.2 50 years 1.83 5.6 (Source：Completed JICA Development Survey Report (2011))
(2) Design Overview
1) Layout
The Project area is located from the Amatuku Jetty at the north end to the south until before the private concrete wall, which was 177 m as shown in Figure 5.1.
Figure 5.1 Final Layout Design (Source: JICA Expert Team)
5-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
2) Beach Profile
a) Gravel Section The initial profile of gravel section (crest elevation, backshore width and foreshore slope) was set as follows;
➢ Crest Elevation: +4.0 m (same as that for natural beaches on the lagoon side)
➢ Backshore Width: 6.0 m (based on the analysis of wave run-up)
➢ Foreshore Slope: 1:3.5 (same as that for natural beaches on the lagoon side)
b) Sand Section The design foreshore slope was decided as 1:11 referring to the existing nearby natural beach and with consideration of stability and quantitative point of view. Design of the beach profile is shown in Figure 5.2
Backshore Width : 6m
Crest Elevation: +4.0m 1 : 3.5 Gravel Crest for Sand: +3.0m MHWL +2.8 MWL +2.0 1: Sand 10
Beach Width(in HWL) : about 10m Figure 5.2 Final Profile Design (Source: JICA Expert Team)
3) Groin
Considring the stablity of armor rock, it is recommended to take 2-layer thickness and required weight for armor rock was determined by the stability analysis using Hudson’s Formula as follows; 1.0 ton/unit for first layer and 0.5 ton/unit for second layer.
The determination for length of groin is important to secure the nourished sand against the risk for sand discharge due to wave action hereafter. The position at the head part of the groin was determined taking into account the position of the toe part for the predicted stable foreshore slope with some clearance until the toe part of the groin. The final design of the groin is shown in Figure 5.3.
5-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Figure 5.3 Final Design of the Groin (e.g., North) (Source: JICA Expert Team)
4) Backshore Stone
The layout and detail of the final proposed backshore armor stone are shown in Figure 5.4.
(1) Layout Plan of Backshore Stone
(Continued to next page)
5-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(2) Detail of Backshore Stone Figure 5.4 Final Design of Backshore Stone (Source: JICA Expert Team)
5.3 Quantity Calculation
Based on the detailed drawing, the quantity for each material was calculated as shown in Table 5.4. Table 5.4 Comparison for Summary of Quantity Item Unit Quantity 1. Gravel Mining and Transportation - Gravel Mining m3 3,204.0 - Gravel Transportation m3 3,204.0 2. Groin - Unloading for Armor Stones m3 754.0 - Core Placing and Leveling m3 388.0 - Armor Placing and Leveling m3 754.0 4. Gravel Nourishment - Gravel Filling and Leveling m3 2,816.0 5. Sand Nourishment - Sand Transportation m 3 3,864.0 - Sand Filling and Leveling m 3 3,864.0 6. Backshore Stone - Stone Installation pcs 200 (Source: JICA Expert Team)
5-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu (Phase-II, Phase-III) Summary of Final Report
6. Project Implementation Plan
6.1 Construction Planning
(1) Procurement
1) Construction Materials
Table 6.1 shows the procurement schedule for the construction materials. Table 6.1 List of Construction Materials Materials Tuvalu Fiji Armor stone ○ Core materials ○ ○ (Source: JICA Expert Team)
2) Manpower
Table 6.2 shows the procurement schedule for manpower. Table 6.2. List of Labor Manpower Tuvalu Fiji Foreman ○ Operator ○ Crew ○ Diver ○ Skilled Labor ○ Unskilled Labor ○ (Source: JICA Expert Team)
3) Construction Equipment
Table 6.3 shows the procurement schedule for the construction equipment. Table 6.3. List of Construction Equipment Construction Equipment Tuvalu Fiji Barge ○ Tug Boat ○ Crawler Crane ○ Backhoe Excavator ○ Wheel Loader ○ 10 t Dump Truck ○ (Source: JICA Expert Team)
6-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu (Phase-II, Phase-III) Summary of Final Report
(2) Construction Method
1) Beach Nourishment
The following explains the beach nourishment procedure including the gravel collection on Funamanu Island and Papa Elise Island.
a) Removal of the Existing Concrete Debris on the Coastline of the Nourishment Area ➢ The existing concrete debris on the coastline will be shifted to a nearby area using a backhoe excavator prior to backfilling the nourishment area with gravel.
b) Gravel Collection ➢ First, a backhoe excavator for gathering gravel from the tidal area and fuel will be brought directly to Funamanu Island and Papa Elise Island by a barge at high tide. The existing concrete debris on the coastline will be shifted to a nearby area using a backhoe excavator prior to backfilling the nourishment area with gravel.
➢ Gravel will be collected from the west and the east side of Funamanu Island and the west side of Papa Elise Island.
Figure 6.1 shows the location of the mining gravel.
Figure 6.1 Location of Mining Gravel (Source: JICA Expert Team)
c) Transportation of Gravel from Funamanu and Papa Elise Island to Pilot Construction Site* ➢ Gravel will be loaded onto the 20 t barge using a backhoe excavator.
➢ The 20-t barge will be towed by two fisher boats and will be transported using a tug boat (160 hp).
6-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu (Phase-II, Phase-III) Summary of Final Report
➢ Three 20 t barges will be towed by a tug boat (160 hp) to the construction site.
➢ Gravel will be dumped directly on the gravel nourishment area.
* In actual construction, a 1,800 t barge and a tag boat of 1,200 horse power was used for gravel collection with securing some clearance between sea bed and ship bottom. d) Filling and Leveling Gravel ➢ Gravel will be filled and leveled by a backhoe excavator and a wheel loader.
e) Sand Transportation ➢ Sand to be used for the sand nourishment will be transported by four dump trucks from the stockpile located 10 km north of Fongafale Island.
f) Sand Filling and Leveling ➢ Sand will be filled and leveled by a backhoe and a wheel loader
g) Groin ➢ Armor stones to be used for the groin will be loaded onto the big barge in Fiji and that big barge will be transported by the tug boat to Tuvalu.
➢ Once the barge arrives at the pilot construction site, armor stones will be dumped directly on the groin area.
➢ Installation work of armor stones and filling work of core materials will be carried out from the land side and the seaside according to the construction procedure.
➢ The work from the sea side will be carried out by the backhoe on the self- propelled barge with the divers. The work from the land side will be carried out by a backhoe and a wheel loader
h) Ancillary Facilities (Backshore Stone) ➢ Armor stones (1.5 ton) will be installed as a backshore stone along the land boundary of gravel nourishment using a backhoe.
6-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu (Phase-II, Phase-III) Summary of Final Report
6.2 Implementation Schedule
(1) Construction Stage
The construction schedule is shown in Table 6.4. Table 6.4 Construction Schedule
Description 1st month 2nd month 3rd month 4th month 5th month 6th month 7th month Mobilization and Preparation
Site clean-up
Gravel Mining
Groin
Gravel Nourishment
Sand Nourishment
Backshore Stone
Demobilization
(Source: JICA Expert Team)
(2) Implementation Schedule
Construction period is expected to take about 6.2 months. Activities for the pilot construction should be carried out taking into account the oceanographic conditions (i.e., during the monsoon season, implementation of the beach nourishment should be avoided). After the completion of the pilot construction, monitoring will be carried out at the pilot construction site. Table 6.5 presents the overall implementation schedule. Table 6.5 Implementation Schedule (Pilot Construction and Monitoring)
Month Work Items 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Tender Stage
Construction Stage
Monitoring Stage
(Source: JICA Expert Team)
6-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
7. Environmental and Social Considerations
7.1 Overview
As per Tuvalu’s EIA regulation (Environment Protection (Environmental Impact Assessment) Regulations 2014) requirements, a Preliminary Environmental Assessment Report (PEAR) was prepared for the Project taking into account also the requirements of JICA Guidelines for Environmental and Social Considerations 2010. The PEAR was submitted to the Ministry of Foreign Affairs, Trade, Tourism, Environment and Labour (MFATTEL) on March 2015 and subsequently was approved on April 2015. The PEAR and approval letter are attached in the Appendix.
7.2 Outline of Tuvalu’s EIA Regulation
Figure 7.1 shows the main flow of the EIA approval procedure as stipulated in the EIA Regulations.
Preparation/submission of PEAR
Review of PEAR by DOE Review by EATF if necessary
Decision by the Minister
No potential Potential significant impact significant impact Preparation/submission of Full EIA Public consultation
Review of Full EIA by DOE
Review of Full EIA by EATF
Decision by the Minister
Project approval Project disapproval
Figure 7.1 Main Flow of the EIA Approval Procedure (Source: Environment Protection (Environmental Impact Assessment) Regulations 2014)
7-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
7.3 Scope of PEAR
The scope of the PEAR was identified through a scoping exercise based on JICA’s environmental guideline, which provides a list of items to be considered in the scoping process. Items rated as having potential negative impacts through the scoping were for example, air pollution, water pollution, waste, noise, ecosystem and topography, and these items were subsequently assessed in more detail and appropriate mitigation measures considered. An Environmental Management Plan and monitoring plan were also prepared based on the impact assessment.
7.4 Conclusion
Main findings of the PEAR are summarized as follows:
One of the primary environmental concerns during the construction stage was the possibility of coral damage mainly during gravel collection works. Hence to minimize such damage, various mitigation measures were planned (e.g. entrance and exit of reef area to be allowed only during high tide to minimize contact with coral) together with a coral monitoring plan. Otherwise, since the construction is of relatively small scale and short duration, and providing that the proposed mitigation measures and monitoring programs are appropriately implemented, environmental impacts of the Project were predicted to remain within minor to moderate level.
In order to check the long-term impacts of the Project, monitoring activities were planned to continue for few years in the post-construction phase namely for coral, marine life and shoreline topography.
Two public consultation meetings (Funafuti community and Falekaupule) were held to explain the basic plan of the Project and likely environmental impacts and planned mitigation measures. All the participants were supportive of the Project once their concerns were answered. The minutes of the meeting are attached to the PEAR.
7-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
8. Public Consultation and Project Coordination Committee (PCC)
8.1 Overview
This chapter summarizes the implementation procedures of the public consultation and Project Coordination Committee (PCC) in obtaining an agreement on plan and design of the beach nourishment using coral gravel and sand, and their relative reports. Figure 8.1.1 shows the implementation flow of the public consultations/stakeholder meetings with Funafuti communities and the PCC with the Government of Tuvalu.
First PCC in Phase-1 on 6 June 2012 Agreement on the contents of the inception report. Clarification of issues to be considered during the project period among
the Government of Tuvalu, stakeholders, and JICA.
1 Stakeholder meeting with Funafuti communities (Jul., Oct. 2012, 7-16 Feb 2013) -
Introduction and basic explanation of the Project. Phase Confirmation on the degree of understanding of the project Agreement on issues regarding the detailed design of the pilot project. Clarification of issues to be discussed and finalized before the implementation. Second PCC in Phase-1 on 27 February 2013 Discussion on the interim report and the vision of the pilot project
First PCC in Phase-2 on 4 February 2015 Review of interim report Obtain agreement for basic points of the Project Stakeholder meeting with 1) representatives of Falekaupule on 19 February, 2) Funafuti communities on 23 February, and 3) Falekaupule on 24 February 2015
Confirmation on objective and concept of the Project
Confirmation on the basic plan 2 - Request for participation in beach control after construction Explanation on possible environmental impact and its mitigation
Phase measure Second PCC in Phase-2 on 25 February 2015 Obtain agreement for final planning and design for the beach nourishment Request for participation in monitoring and maintenance from C/P and relative agencies Third PCC in Phase-2 on 17 June 2015
nd Obtain agreement on progress report (including contents of 2 PCC) Figure 8.1 Implementation Flow of the Public Consultation and PCC (Source: JICA Expert Team)
8-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
8.2 Stakeholders of Public Consultation and PCC
Figure 8.2.1 shows the stakeholders involved in the public consultation and the PCC. In the figure, the area enclosed with a red line shows the stakeholders of PCC, while the area enclosed with a blue line shows the stakeholders of the public consultation. The former includes the C/P (Department of Environment, MFATTEL), the Public Works Department, Department of Land and Survey, Department of Fisheries, METS. While, the latter includes the Funafuti communities (Funafuti Kaupule, Funafuti Falekaupule Funafuti Women Group, Fisherman Group, Masaua Group, and the community from the outer islands).
Falekaupule is the supreme decision-making body of all matters in the Funafuti communities that are of public interest or political importance. Therefore, public consultations/stakeholder meetings were conducted with permission from the Falekaupule first, then discussions with other community members were conducted, and final decisions were obtained through the meeting with the Falekaupule. The meetings for Falekaupule and other communities were conducted separately because other community members are not fully able to voice out their concerns. with the presence of Falekaupule.
Stakeholders of PCC
Stakeholders of Public Consultation
Figure 8.2 Stakeholders of Public Consultation and PCC (Source: Completed JICA Development Study (2011))
8-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
8.3 Results from Public Consultation and PCC
The list below shows the summary of the items that had been agreed/reconfirmed through public consultations and PCC, and the summary of items to be confirmed with stakeholders before the pilot construction.
Items that had been agreed/reconfirmed through the public consultations and PCC
➢ Objective and concept of the Project ➢ Characteristics of the beach nourishment ➢ Project area and its boundaries ➢ Procurement of gravel from tips of Funamanu Island and west tip of Papaelise Island ➢ Procurement of sand from NZ Project ➢ Design of beach profile ➢ Installation and design of north and south groins and procurement of armor rocks ➢ Placement of backshore stones ➢ Securing space for boat landing ➢ Reuse of existing concrete blocks at the Project site ➢ Participation and cooperation to the monitoring and maintenance of the government and the other communities Issues to be confirmed with stakeholders before the pilot construction
➢ Locations of the space for boat landing ➢ Details of construction schedule and the work area during construction ➢ Details of mitigation measures to minimize environmental impacts
8-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
9. Construction
9.1 Summary of Construction Work
The construction was implemented from 15 June to 23 Dec 2015 about 6.3 months. Table 9.1 shows actual construction schedule comparing with that of initial plan and main work item and its actual quantity were summarized in Table 9.2 and 9.3, respectively. Figure 9.1 shows representative photos during construction. Table 9.1 Construction Process Sheet (Master Schedule and Actual)
(Source: JICA Expert Team)
Table 9.2 Main Work Item and Quantity No. Work Item Content Specification 1 Preparation ➢ Preparation in Fiji and Work transportation for Tuvalu ➢ Preparation of work at the Project site 2 Collection and ➢ Collection and Plan volume of the gravel: 3,204 m3 Transportation transportation from the of Gravel atoll (Papaelise and Funamanu)
9-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
No. Work Item Content Specification 3 Groin ➢ Construction of the north South groin Construction groin and south groin Length: 46.1 m (Riprap slope Crown Height: +4.2 m embankment) Crown Width: 1.3 m Slope: 1:2 (South), 1:1.5 (North) North groin Length: 51.3 m Crown Height: +4.2 m Crown Width: 1.3 m Slope: 1:1.5 4 Gravel ➢ Placing and leveling of Estimated Volume: 2,816 m3 Nourishment gravel Backshore Height: +4.2 m Backshore Width: more than 6 m Slope: 1:3.5 5 Sand ➢ Taking the sand from the Estimated volume: 3,864 m3 Nourishment Borrow Pit No. 2 Slope: 1:11 ➢ Transportation, placing, and leveling of sand 6 Backshore ➢ Installation of armor stone Estimated quantity: 200 pieces Stone along the boundary 7 Procurement of ➢ Rubbish bin 5 sets Equipment ➢ Boat trailer 1 set (Source: JICA Expert Team)
Table 9.3 Estimated and Actual Quantities No. Work Item Estimated Quantity Actual Quantity 2 Gravel Nourishment 3,204 m3 3,327 m3 (West end of Papaelise: 2,207 m3 East end of Funamanu: 1,120 m3) 5 Sand Nourishment 3,864 m3 4,500 m3 6 Backshore Stone 200 pieces 141 pieces (Source: JICA Expert Team)
(Landing on the gravel collection site) (Gravel collection)
9-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(Unloading gravel at construction site) (Leveling work of gravel)
(Laying armor stones on groin surface) (Inspection on cross section of groin)
(Sand collection at Borrow Pit No.2) (Placement of sand on the site)
(Levelling of sand) (Placement of backshore stones) Figure 9.1 Construction Photos (Source: JICA Expert Team)
9-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
9.2 Effects of the Construction of the Beach Nourishment
The effects expressed by the construction of the beach nourishment were presented in this section. The beach nourishment in the Project was implemented to expect user and environment friendly functions as well as to protect the land against beach erosion and wave over topping. Taking into account such points of view, the outcome of the Project will be discussed as the following points and presented in the following sections:
1) Protection function
2) Coastal utilization
3) Coastal environment
(1) Protection Function
After the completion of construction on 24 December 2015, Cyclone Ula was approaching Tuvalu. During this storm period, south or southwest strong waves hit the lagoon side on Fongafale Coast. This is only the opportunity to discuss the effects on protection of land, even though the wave condition during this period was not to the highest extreme condition.
From the result of the interview survey from the residents who are living near the coastal area on the lagoon side, the following information could be obtained:
Before the Project, wave intruded up to their property, easily. However, there was no wave intrusion at their property at this time even in the high wave condition (see Figure 9.2). The common opinions from the residents are that forming the gravel beach is surely effective to protect the land. On the other hand, some of the residents anticipated the gradual loss of gravel due to the same degree of storm frequently hitting.
As a result, the function to protect the land can be surely achieved as far as the beach maintains the present condition (width). However, it is not sure that the beach can maintain the necessary width for a long time or not under the same condition since hitting of storms is frequent. Continuous monitoring is still required to evaluate the validity of the proposed beach.
9-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Before the Implementation After the Implementation Figure 9.2 Comparison of Wave Condition Before and After the Implementation (in high wave condition) (Source: JICA Expert Team)
(2) Coastal Utilization
After the implementation, a lot of scenes are evident showing that the Project beach is well utilized by the local people. Children play using both spaces of the sandy area and shallow water area as shown in Figure 9.3. The groin and backshore stones are also well utilized as expected (Figure 9.4).
Figure 9.3 Beach Use at the Shallow Water and Sandy Area (Source: JICA Expert Team)
9-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Figure 9.4 Use of Constructed Coastal Facilities (Source: JICA Expert Team)
(3) Coastal Environment
According to the information from some residents, fishes seem to have increased in comparison prior to the implementation of the Project. A lot of fishes can be seen easily especially near the groin as shown in Figure 9.5.
Landscape was improved significantly as shown in Figure 9.6.
Figure 9.5 Fishes in the North Groin (Source: JICA Expert Team)
9-6 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Before the Implementation After the Implementation Figure 9.6 Comparison of Coastal Landscape (Source: JICA Expert Team)
9-7 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
10. Monitoring Plan
10.1 Overview
The beach monitoring work has been undertaken periodically for 2 years since the completion of pilot construction on December 2014 up to on November 2017. The monitoring are divided into four items as;
1) Coastal hydraulic condition
2) Beach change at and surrounding the Project site
3) Beach change at gravel extraction site
4) Marine Environment
Even though such monitoring works were mainly undertaken by JICA Expert Team, the Tuvaluan counterpart (C/P) also joined as much as possible, as one of technical transfer and capacity development program.
The objective, method/Equipment and related C/P for each monitoring works are shown as follows. Table 10.1 Items and Method of Monitoring for Hydraulic Condition Item Objective Method / Equipment C/P Wave and Current To know the external Bottom mounted Fisheries Observation condition for beach change Wave-Current Meter (Wave MET Office Hunter) Data Collection for To know the external Data collection from MET MET Office Tide condition for beach change office in Tuvalu and Web Site (Australian mythological Services) Data Collection for To know the impact to beach Data collection from MET MET Office Cyclone Record change due to special event office in Tuvalu and Web site (Source: JICA Expert Team) Table 10.2 Items and Method of Monitoring for Beach Change at and surrounding the Project Site Item Objective Method / Equipment C/P Change in Beach To know the change in beach Beach profile survey using Environment profile profile and remaining rate for auto level and scale tape Dept., Land sand and gravel &Survey Change in To know the local change in Positioning survey using Dept. Shoreline position of shoreline handy-type GPS surrounding the Project site including the Tuvaluan Reclamation Project site Change in To know the local change of Taking photos from fixed Environment Condition of Beach beach condition in and points and aerial photographs Dept., surrounding the Project site by Drone Kaupule
10-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Item Objective Method / Equipment C/P Satellite Image To know the overall change Comparison of shoreline Land in position of shoreline using the satellite image &Survey surrounding the Project site Dept including the Tuvaluan reclamation Project site (Source: JICA Expert Team) Table 10.3 Items and Method of Monitoring for Beach Change at Gravel Borrow Site Item Objective Method / Equipment C/P Change in Beach To know the change in beach Beach profile survey using Environment profile profile at west tip of auto level and scale tape Dept., Land Papaelise and east tip of &Survey Funamanu Dept. Change in To know the local change in Positioning survey using Shoreline position of shoreline at west handy-type GPS tip of Papaelise and east tip of Funamanu Change in To know the local change of Taking photos from fixed Environment Condition of Beach beach condition at west tip points aerial photographs by Dept., of Papaelise and east tip of Drone Kaupule Funamanu Satellite Image To know the overall change Comparison of shoreline Land in position of shoreline at using the satellite image &Survey west tip of Papaelise and east Dept tip of Funamanu (Source: JICA Expert Team) Table 10.4 Items and Method of Marine Environment Item Objective Method / Equipment C/P Water Quality To know the impact to water Measurement of water Environment (Turbidity quality due to the Project turbidity using handy-type Dept. measurement) turbidity meter Existing Corals To know the impact to Transect survey at fix points Environment existing corals at the island Dept. (gravel taking area) due to the Project Marine Life To know the impact to Transect survey at fix points Environment marine biota at the Project Dept. site due to the Project Trial of Coral To know the feasibility for Fixing of coral fragment to Environment Transplantation artificial coral basement stone and visual Dept. transplantation in Tuvalu checking atoll (Source: JICA Expert Team)
10-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
The schedule for each monitoring works are shown in Figure 10.1.
2015 2016 2017 No. Monitoring Item 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12
Wave Curent Observation △ △ △ △ △ maintanance △ △ Monitoring for 1 Data Collection for Tide Hydraulic Condition △ △ △ △ △ △ △ and Cycline
Monitoring for Beach Survey Work on Site △ △ △ △ △ △ △ △ △ △ Change in and 2 Sateliite Image △ △ surrounding the
Project Site Aerialphotograph by Drone △ △ △ △ △
Survay Work on Site △ △ △ △ △ △ Monitoring for Islands 3 Satellite Image △ △ (Gravel Taking Area)
Aerialphotograph by Drone △ △
Water Quality △ △ △ △ △ △ (Turbidity Measurement) Monitoring for Marine Existing Coral and 4 △ △ △ △ Environment Marine Life Trial of Coral △ △ △ △ △ △ Transplanation Figure 10.1 Schedule for Each Monitoring Items
(Source: JICA Expert Team)
10-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
11. Monitoring Result
11.1 Coastal Hydraulic Condition
(1) Tide Observation
The tide observation data from 2015 to 2017 are summarized. The extreme high tide, which is called “King Tide”, commonly appeared from November to April in a year. The tide of 3.4 m in height was observed at 5:00 am of February 19 in 2015. In 2016, 3.2 m was observed at 5:00 am of November 15, and in 2017, 3.2 m was observed at 6:00 pm of March 28.
(2) Wave Observation
Wave at the lagoon side is usually calm, and the significant wave height (H1/3) is around 0.1 m. When the cyclone or tropical depression approaches, the significant wave height becomes about 0.8 m to 1.0 m.
When the storm approaches, at first, wave of frequency lower than 0.1 (wave period of about 10 seconds) will swell and propagate, and when it comes close to the coast and the wind increases in force, wind waves of short frequency of about 0.3 (wave period of about 3 seconds) develop.
Wave direction predominates in the angle which acts on shoreline rightward in the period of from February to June 2015 but from October 2015 to March 2016 predominates in the angle which acts on shoreline leftward and after that, it seems that both direction exist.
(3) Appearance of Cyclone
Tuvalu is located in the low latitude such as around 8 degrees of south latitude. Therefore, it is common that cyclones doesn’t attack directly in Tuvalu. However, when the cyclones or tropical depression approach to Tuvalu, waves at both ocean and lagoon sides become rough. Several cyclones were approached during from 2015 to 2017. The strongest cyclone in the wave observation period was “Cyclone Palm” which was approached in Tuvalu on March 2015. After the completion of pilot construction on December 2014, two typical cyclones approached, which were “Cyclone Ula” on December 2015 and “Cyclone Winston” on
February 2016. In that time, the significant wave height (H1/3) at the lagoon side became
about 0.8 m to 1.0 m, and the maximum wave height (Hmax) became more than 1.2 m.
11.2 Beach Change at the Project Site
Figure 11.1 shows the location map for beach profile survey. The 14 lines are selected in total as monitoring line for beach profile. The interval of each monitoring line is basically every
11-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
20 m, except a few lines. The survey range for on-offshore direction was started from the backshore stones up to 50 m offshore side. The land view photos were also taken from the fixed points with keeping the same angle.
d a e c b
L4 L3 L2 L1 P9 P8 P7 P6 P5 P4 P3 P2 P1 R2 R1
Figure 11.1 Location Map of Profile Survey and Fixed Point Photography Position
(Source: JICA Expert Team)
(1) Comparison of Land View Photo from Fixed Point
Comparison of land view photos from fixed points a and c (Figure 11.1) from the completion of construction on December 2015 to the completion of monitoring period on November 2017 in every 6 months are shown in Figure 11.2. Retreat of the crest part at the backshore gravel part, decrease of elevation and scattering of gravel on the foreshore sandy part was observed at the north side (point a). On the other hand, sand was accumulated at the south side (point c). To improve the beach condition at the north area, the beach maintenance as adaptive measures was conducted. Gravel was removed from the foreshore sandy part and put into the original backshore gravel part. Also, small amount of sand was refilled at the north area.
(2) Comparison of Beach Profile
Figure 11.3 shows the result of beach profile survey at the selected 4 representative lines for 1.3 years from the completion of construction on December 2015 to March 2017 before undertaking adaptive measures. Retreat of crest part for gravel section about 3 m was observed at the north side (P1). The elevation of foreshore part decreased at the north side (P1) and increased at the south side (P9). From the result, southward littoral drift and movement of gravel at the crest part was quantitatively identified. Figure 11.4 shows the comparison of beach profile before and after conducting the adaptive measures on September 2017 and that just after the completion of construction. The crest part could be improved due to executing the adaptive measure. The detail for adaptive measure are described in Chapter 13.
11-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
2015.12.24 2015.12.24
2016.6.14 2016.6.14
2016.12.24 2016.12.24
2017.7.30 2017.7.30
2017.11.5 2017.11.5 (1) Position a (2) Position c Figure 11.2 Comparison of Photos from Representative Two Fixed point
(Source: JICA Expert Team)
11-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Figure 11.3 Comparison of Beach Profile for 1.3 years (Before Conducting Adaptive Measure)
(Source: JICA Expert Team)
Figure 11.4 Comparison of Beach Profile (Before and After Conducting Adaptive Measure and Just After the Construction)
(Source: JICA Expert Team)
11-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(3) Change in Volume for Nourishment Material
The change in volume for nourishment materials, gravel and sand were examined based on the obtained result of beach profile survey.
Movement to foreshore (for gravel)
gravel
sand
Figure 11.5 Image of Gravel Movement (Source: JICA Expert Team)
As the result of visual checking on site, no outflow of gravel to the outer area was observed through the monitoring period. On the other hand, a part of gravel was identified on the foreshore sandy beach. This means a part of filled gravel was just moved from the original backshore gravel section to the foreshore sandy section, as shown in Figure 11.5.
Figure 11.6 shows the change in volume at the original backshore gravel section, calculated from the profile survey results for each monitoring line. From the result,
Decrease of volume with 6% (200 m3) was observed in the beginning from the completion of construction on December 2015 to March 2016. It was caused by the movement of gravel mainly from the crest part of gravel backshore section to the foreshore section due to strong wave action during approaching Cyclone Ula and Winston just after the completion of construction. After that, no significant decrease of volume was observed.
Significant increase of gravel from July to September in 2017 was caused by the implementation of adaptive measure to remove the scattered gravel from the foreshore section to the original crest part at the backshore section.
Gravel Gravel 600 10% Total 400 Total South 2015.12.20 South 5% 2015.12.20 200 1.22 1.22 North 2.10 North 2.10 0 0% -200 3.11 6.22 12.14 3.31 2017.7.28 -5% -400 9.11 11.3
9.11 11.3 (%) Volume in Change Change in Volume (m3) Volume in Change 3.11 6.22 12.14 3.31 2017.7.28 -600 -10% 0 200 400 600 800 0 200 400 600 800 Day Day
Figure 11.6 Change in Volume at Backshore Gravel Section (left: quantity, right: rate)
(Source: JICA Expert Team)
11-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Sand Sand 600 10% Total Total 400 South South 5% 200 North North 0 0% -200 -5% -400 Change in Volume (%) Volume in Change Change in Volume (m3) Volume in Change -600 -10% 0 200 400 600 800 0 200 400 600 800 Day Day Figure 11.7 Change in Volume at Foreshore Sand Section (left: quantity, right: rate)
(Source: JICA Expert Team)
Figure 11.7 shows the change in volume of sand at the foreshore section. Here, the quantity of
gravel shown in Figure 11.6, which was moved from the backshore section to the foreshore section, was eliminated.
Volume of sand was temporally increased about 5% (200 m3), after that gradually decreased. Based on the wave observation result, the wave direction during the cyclone approaching changed to incident from north to south side. This change in wave direction induced the northward littoral drift. Due to this, a part of sand at the southern natural beach transported to the north and overflowed into the Project area through the south groin. However, after that the wave direction change as normal direction to incident from north side and the sand in the Project area transported to the south. A part of sand might be overflowed to the south through the south groin. Further, fine contents of sand were also possibility to move to offshore. However, total decrease of volume for sand was very small about 5% for 2 years.
Figure 11.8 shows the change in total volume of sand and gravel. Decrease of total volume for combined gravel and sand was about 2% (200 m3). All of this decrease was caused by decrease of sand.
Gravel + Sand Gravel + Sand 600 10% Total Total 400 South 5% South 200 North North 0 0% -200 -5% -400 Change in Volume (m3) Volume in Change -600 (m3) Volume in Change -10% 0 200 400 600 800 0 200 400 600 800 Day Day Figure 11.8 Change in Total Volume (left: quantity, right: rate)
(Source: JICA Expert Team)
11-6 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
11.3 Beach Change at Reclamation Area
The big-scale reclamation project was also undertaken by the government of Tuvalu at 0.7 km far from the Project site in the almost same period on November 2015. About 100,000 m3 of dredged sand was directly filled into the coastal area with a 300 m distance and 80 m width without any enclosure. This reclamation activity was completed in the latter part of December 2015. However, additional sand filling and construction of two groins were conducted due to significant sand loss which was caused by the attack of Cyclone Ula which approached to Funafuti Atoll from the end of December 2015 to the beginning of January 2016. Finally, it was completed in June 2016.
The change in position of the shoreline at the reclamation project area was measured by using a handy type GPS. Figure 11.9 shows the change in the position of the shoreline for three months from December 2015 just after the completion of the sand pumping work. During this period, sand was filled into the existing beach with 300 m distance and 80 m width, and no coastal structure, such as groin, was constructed. After the approach of Cyclone Ula on 23 January 2016, significant retreat of the beach with average width of about 20 m and maximum width of 25 to 30 m was observed. Most of the disappeared sand was moved to the north side by wave action. Total volume for sand discharge was estimated to 34 %. Figure 11.10 shows the change in the position of the shoreline after the construction of both groins, and Figure 11.11 shows the change in condition of the beach before reclamation and before and after the construction of groins. After the construction of groins, the reclamation area could maintain mostly stable condition.
11-7 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
b c a d Shoreline 2016. 6.30 8:30 Scarp 2016.12.14 13:00 2016. 6.30 8:30 2017. 3.30 13:30 2016.12.14 13:00 2017. 8. 6 10:30 2017. 3.30 13:00 2017. 11. 5 10:30 2017. 8. 6 10:30 2017. 11. 5 10:30 0 200
Figure 11.9 Shoreline Change Before Figure 11.10 Shoreline Change After the Construction of Groin the Construction of Groin
(Source: JICA Expert Team) (Source: JICA Expert Team)
Figure 11.11 Change in Beach Condition at Reclamation Area
(Source: JICA Expert Team)
11.4 Beach Change at Gravel Extraction Site
The beach monitoring was undertaken at Funamanu and Papaelise Island for 2.5 years since before the extraction of gravel. Total volume for extraction of gravel was about 3,300 m3, where 2,200 m3 from the west tip of Papaelise and 1,100 m3 from the east tip of Funamanu. The monitoring survey and taking photos from the fixed points were carried out at the both tips of Funamanu and the east side of Papaelise Island. Figure 11.12 and 11.13 shows the monitoring line and position of taking photos for each monitoring area. The comparison of
11-8 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
satellite image before and after the extraction of gravel was also carried out to check the special change of shoreline.
Figure 11.12 Location of Beach Monitoring at Funamanu Island
(Source: JICA Expert Team)
Figure 11.13 Location of Beach Monitoring at Papaelise Island
(Source: JICA Expert Team)
Figure 11.14 and 11.15 shows the change in beach profile at three monitoring locations for 2.5 year since before the gravel extraction. As the result, there was no remarkable difference since before the gravel extraction at Funamanu Island. At Papaelise Island, some degree of retreat was identified due to gravel extraction activity, however, no significant change after the extraction was observed. Form the result, it was proven that there was no negative impact to surrounding beach due to extraction of gravel.
11-9 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
5 5 2015.6 FN0 2015.6 FN1 2015.12 4 2015.12 4 2016.3 2016.3 2016.6 2016.6 3 3 2016.12 2016.12 2017.4 2017.4 M.S.L. M.S.L. 2 2 C.D.L.(m) C.D.L.(m) 2017.11 2017.11 1 1 Lagoon side Ocean side Lagoon side Ocean side 0 (m) 0 (m) -60 -40 -20 0 20 40 60 -40 -30 -20 -10 0 10 20 30 40
5 2015.6 FN2 4 2015.12 2016.3 3 2016.6 2016.12 2017.4 M.S.L.
C.D.L.(m) 2 2017.11 1 Lagoon side Ocean side 0 (m) -40 -30 -20 -10 0 10 20 30
Figure 11.14 Change in Beach Profile at East Tip of Funamanu Island (Source: JICA Expert Team)
5 5 2015.6 FS0 2015.6 FS1 2015.12 4 4 2015.12 2016.3 2016.3 2016.6 3 3 2016.6 2016.12 2016.12 2017.4 M.S.L. 2 2017.4 M.S.L. C.D.L.(m) 2 2017.11 C.D.L.(m) 2017.11 1 1 Lagoon side Ocean side Lagoon side Ocean side 0 (m) 0 (m) -80 -60 -40 -20 0 20 40 60 -60 -40 -20 0 20 40 60
5 2015.6 FS2 4 2015.12 2016.3 3 2016.6 2016.12 M.S.L. 2 2017.4 C.D.L.(m) 2017.11 1 Lagoon side Ocean side 0 (m) -60 -50 -40 -30 -20 -10 0 10 20 30 Figure 11.15 Change in Beach Profile at West Tip of Funamanu Island (Source: JICA Expert Team)
5 5 PA1 2015.6 PA2 2015.6 4 2015.12 4 2015.12 2016.3 2016.3 3 2016.6 3 2016.6 M.S.L. 2016.12 M.S.L. 2016.12 2 2 2017.4 2017.4 1 1 tentative height(m) tentative tentative height(m) tentative Lagoon side 0 Ocean side Lagoon side Ocean side (m) 0 (m) -40 -30 -20 -10 0 10 20 30 -30 -20 -10 0 10 20
5 PA3 2015.6 4 2015.12 2016.3 3 2016.6 M.S.L. 2 2016.12 2017.4 1 tentative height(m) tentative Lagoon side Ocean side 0 (m) -20 -10 0 10 20 30
Remark) There was no reference point for elevation at Papaelise, so the highest point was set to 4 m Figure 11.16 Change in Beach Profile at West Tip of Papaelise Island (Source: JICA Expert Team)
11-10 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
11.5 Summary of Beach Monitoring
The Project beach could maintain the stable condition even though it was struck by high waves during the approaching cyclone. The discharge rate for combined gravel and sand was about 3% for two years.
Sand, which was filled in the foreshore section, has a tendency to shift to the south in total due to littoral drift, and a part of the shifted sand that overflowed to the south beach. Also, a part of the fine contents of sand can possibly be moved to the offshore side. Total discharge rate for sand was estimated to be about 5% for two years.
A part of the gravel, which was filled to the backshore section, were moved to the foreshore sandy part and were scattered by continuous wave action. Due to this, the crest line of gravel section had a little retreat with approximately 1 m in average and 3 m at maximum in the north part of the Project area. However, gravel was just moved from the backshore to the foreshore side and no discharge of gravel to the outer area was observed.
No negative impact to the surrounding coast was identified both at the Project site and the gravel borrow site in Funamanu and Papa Elise islands.
11.6 Marine Environment
(1) Water Quality
While there was some occasional elevation in turbidity during sand-placement works, its range of impact was limited to a small area and returned to pre-construction levels 1-2 days after sand-placement works was completed. In the post-construction phase, no major increase in turbidity were recorded around the Project site. From the visual checking on site in post project stage, the water transparency after the nourishment seems to be improved than before as shown in Figure 11.17
Figure 11.17 Condition of Water Transparency in Post Construction Stage
(Source: JICA Expert Team)
11-11 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(2) Coral
During gravel collection works, no notable coral damage was observed except for the few corals that were sparsely distributed where the barge anchored. Many corals at the lagoon side were bleaching and died in recent one to two years due to high water temperature at the lagoon side, and such area expanded (Figure 11.18).
Figure 11.18 Condition of Existing Natural Corals (already died)
(Source: JICA Expert Team)
(3) Marine Life
No notable changes in marine life were observed between pre- and post-construction stages around the Project site. In fact, the north groin appears to be functioning as a new habitat for various young fishes as many young fishes were observed along the groin in the post-construction stage (Figure 11.19).
Figure 11.19 Forming of New Fish Habitat
(Source: JICA Expert Team)
(4) Trial of Coral Transplantation
While some corals showed some sign of growth after transplantation, most of the transplanted corals were eventually bleached or dead by around 6 months (Figure 11.20). One of the reason for these deaths may be due to the higher than average water temperature that was experienced in the Pacific region from the strong El Nino that persisted during 2014-2016.
11-12 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(1) Just After the Fixing (December 2015) (2) 5 Months Later (already died) Figure 11.20 Condition of Transplanted Coral
(Source: JICA Expert Team)
11-13 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
12. Beach Management and Maintenance
12.1 Structure and Overview
The structure of beach management of the Project is shown in Figure. 12.1. Beach management was defined as an all-inclusive term of activities that are required to maintain the beach area in good condition not only in protection but also in beach use and environment. The “beach management” consists of three categories of activities, which are beach monitoring, beach maintenance, and PR and environmental education, also shown in the figure.
Plan, Design, Construction
Beach Management (Ch.12)
(1) Beach Monitoring (Ch.10 & Ch.11)
Beach profile change Beach use and environment situation Marine environment
Beach Maintenance (2)
Community-based Beach Maintenance (Ch.12)
Beach cleaning
Regulation on illegal/unexpected activities
Adaptive Measure (Ch.13) Reprofiling of beach Re-nourishment
PR and Environmental Education (Ch.14)
Relationship: (1) Adaptive measure is prepared based on beach monitoring results. (2) Improving public awareness by PR and environmental education is essential to establish community-based beach management as it requires their participation. Figure 12.1 Structure of Beach Management (Source: JICA Expert Team)
12-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
12.2 Community-based Beach Maintenance
The maintenance activities done by the local communities (i.e., Funafuti Kaupule and residents) were monitored for about two years after the completion of the beach nourishment. This section summarized a situation of beach cleaning as the representative example of community-based beach maintenance.
Since the beach is a public area where a lot of people visit and use it in a daily basis, beach cleaning in high frequency is necessary to maintain the good environment of the area for the beach users, as well as for the communities. Since beach cleaning was quite a new activity for the people in Funafuti, at first, beach cleaning event was held to make people familiar with the activity and understand its effect. In this regard, beach cleaning event was held before starting the construction as shown in Figure 12.2.
Figure 12.2 Beach Cleaning Event Involving Kaupule and the Residents (Source: JICA Expert Team)
Funafuti Kaupule, a management body of the Project, began beach cleaning once a week or once in two weeks every Fridays from 15 January 2016, which was just after the completion of the construction. JET had monitored their beach cleaning activities and instructed them to make beach cleaning more effective and sustainable in the future.
As of December 2017, about two years after the construction, it was confirmed that beach cleaning was established as a weekly task for Funafuti Kaupule and it contributed to maintain the Project beach with good condition. Beach cleaning is mainly conducted by the officials and the average number of participants were about 10. Residents’ participation was generally few but they join occasionally upon Kaupule’s request. Figure 12.3 shows the photos during beach cleaning by Kaupule and the residents.
12-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(15 January, more than 30 participants) (12 February, about 10 participants)
Figure 12.3 Beach Cleaning by Kaupule and the Residents (Source: JICA Expert Team)
12.3 Proposal and Practice for Sustainable Beach Management
Beach nourishment in general requires periodic maintenance works such as re-nourishment and reprofiling after implementation to satisfy its required function. Details of maintenance work and its frequency differ based on purpose, natural conditions, and nourishment materials.
In the Project, as public awareness on beach use and environment was rapidly increased as summarized in Chapter 14, it was required to maintain the beach at a level where it can be used pleasantly like a playground. To respond to such requests, the community and the government decided to implement maintenance works and would continue periodic re-nourishment and reprofiling on a yearly basis. The first maintenance work had been implemented mainly by Funafuti Kaupule under the supervision of the JICA Expert Team to learn basic procedure and methods (see Chapter 13 for details of this adaptive measure). In addition, to make the maintenance works sustainable in the future, a kind of win-win relationship among schools, community, and the government was proposed as shown in Figure 12.4. One example of this relationship is that the school will hold a beach sports event involving the community and the community will do beach maintenance in return so that the beach area can be used for the festival, which was actually practiced in the Project as the second joint event in 2017 (see Chapter 14 for details of the joint event). It might not be so easy to establish such kind of sustainable maintenance structure in practice, however, considering the drastic changes in people’s awareness and activities through the Project, it is possible that this can be realized.
12-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(1) Planning of Events
(2)Beach Maintenance School, Community Residents (3) Public Participation
Support for maintenance work The Develop education system on coastal (procurement of Government materials etc.) environment
Figure 12.4 Proposed Sustainable Beach Management Structure (Source: JICA Expert Team)
12-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
13. Adaptive Measure
13.1 Overview
Based on the monitoring results for beach profile, a slight decrease of backshore width for gravel section was observed in the north area. Even though these phenomena are one of the natural processes of beach behavior and significant impact on protection function is not affected, it is not preferable for the attractive use of the beach on sandy foreshore area. Also, the possibility of further retreat of backshore width is anticipated depending on the wave condition. Thus, it was recommended to undertake adaptive measure as one of the maintenance works taking into account the actual beach change obtained by the monitoring results to maintain both “protection function” and “desirable beach use” of the beach sustainably. A realistic, feasible, and easy measure is required taking into account their own manpower, equipment, and skills level, if possible.
13.2 Summary of Beach Change for 1.3 Years after Construction
Figures 13.1 and 13.2 showed the change in beach condition in the north and south areas for 1.3 years after the completion of construction. Gravel, which was originally positioned at the backshore area, was moved to offshore side and scattered on foreshore sandy part in the north area. On the other hand, sand accumulation was observed in the south area. From the result, two phenomena, which are gravel movement from backshore to foreshore side and littoral movement of sand from north to south, might be combined on beach behavior after the nourishment as shown in Figure 13.3.
2015.12.24 2017.3.31
Figure 13.1 Change in Beach Condition in the North Area (Source: JICA Expert Team)
13-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
2015.12.24 2017.3.31
Figure 13.2 Change in Beach Condition in the South Area (Source: JICA Expert Team)
Movement to foreshore (for gravel) Littoral Movement (for sand)
gravel sand sand gravel
Figure 13.3 Beach Behavior after Nourishment (Source: JICA Expert Team)
13.3 Proposed Adaptive Measure
(1) Feasibility for Undertaking Adaptive Measure by the Tuvaluan Side
➢ As adaptive measure shall be undertaken at the community level by Tuvaluan side, it is required to consider their own manpower, equipment, and skills level, if possible.
➢ According to the monitoring results, the gravel did not flow out to the outer area; Therefore, there is no need to fill again, it just needs to consider re-position of gravel from foreshore to original backshore area.
➢ Sand was gradually decreased in total, however, the decreased volume was quite small. Considering the present and near future condition for stock of sand in Tuvalu, it might not be an issue for taking sand from sand stockpile for refill of sand to the beach.
➢ Funafuti Kaupule and the people have now high consideration and passion for maintaining the Project beach. It is expected to carry out the proposed measure as “community-based activity” and “educational program in the school”.
13-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
➢ Proposed adaptive measure will be easy and has a simple method. No special equipment, skills, and high manpower are required.
(2) Proposed Adaptive Measure
Proposed adaptive measures are the following two activities (Figure 13.4).
1) Re-position of gravel from foreshore to original backshore area.
2) Refill of small amount of sand in the north area. According to the monitoring result, about 100 to 200 m3 of annual sand refill might be required.
It is proposed that the sand is refilled only in the north area as shown in Figure 13.5 taking into account expected natural littoral sand movement to the south. Due to the existence of two different seasons in Tuvalu, which are the summer season (cyclone season) and the winter season (calm season), it is recommended to undertake the site work during the winter calm season. Also suitable timing shall be considered taking into account the schedule of active beach use such as beach sports event, etc. Figure 13.6 shows the relation of one of the proposed schedules for executing the adaptive measure and seasonal change of wave condition. +
Figure 13.4 Proposed Adaptive Masure (Source: JICA Expert Team)
Figure 13.5 Area for Sand Refill (North Area) (Source: JICA Expert Team)
13-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Jan. Feb. Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Mainteance Work 1st time 2nd time
Beach Events Suitable Suitable
Wave Height
Wave Direction (to beach)
Cyclone Season Cyclone Season Figure 13.6 Example of Time Schedule for Adaptive Measure (Source: JICA Expert Team)
13.4 Implementation
The proposed adaptive measure was implemented by Funafuti Kaupule with public participation following three steps as shown below.
Step1: Removal of gravel on the foreshore area and throw into the original backshore area using the excavator which is owned by Funafuti Kaupule.
Step2: Removal of remaining gravel on foreshore area manually, which is carried out as educational program of the primary school in Funafuti.
Step 3: Transportation of stocked sand and refill to the beach with permission from the government of Tuvalu.
Figures 13.7 to 13.9 show the site work for each step, and Figure 13.10 shows the comparison of beach condition before and after the work. The beach was drastically changed and the similar condition of the beach just after the completion of nourishment was recovered by conducting the adaptive measure .
13-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Before the work Collecting gravel
Push to backshore After high tide
Figure 13.7 Removal and Dumping of Gravel by Excavator (Step 1) (Source: JICA Expert Team)
1st (1st Sep, 2017) 2nd (6th Sep, 2017)
3rd (7th Sep, 2017) After the Work
Figure 13.8 Removal of Remaining Gravel Manually (Step 2) (Source: JICA Expert Team)
13-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Sand transportation from stockpile Throw into the Beach
After leveling Before leveling
Figure 13.9 Transportation and Refill of Sand (Step 3) (Source: JICA Expert Team)
Before After
Figure 13.10 Comparison of Beach Condition Before and After the Work (Source: JICA Expert Team)
13.5 Obtained Effect
Obtained effects are summarized as follows:
➢ Beach condition could be recovered as almost the same level as the initial condition just after the nourishment.
➢ It was proven that the proposed measure was easy and simple. It was possible to implement at the community level in Tuvalu.
➢ It was proven that the removal of gravel manually was very effective than expected. This activity was also very effective to enhance people awareness in maintaining the beach.
13-6 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
➢ The site work could be minimized to use natural wave action and tidal change effectively. (Collected gravel by excavator originally contained sand. But this contained sand could be naturally washed away by sea water during high tide condition. Also, refilled sand to the beach could naturally make smooth slope due to wave action during high tide.)
13.6 Subject
Several subjects were also revealed through the actual implementation of adaptive measure.
➢ Maintaining the passion and motivation continuously to take action of the proposed maintenance work by the community (Funafuti Kaupule and Funafuti people), especially in case of after retirement of the present organization members of Kaupule (replaced new member might not be so familiar to the beach maintain).
➢ Maintenance of equipment (excavator) to be used in the site work for the maintenance of the beach (it might be necessary to consider the procurement of equipment (excavator) in the near future).
➢ Securing of sand for maintenance (support and understanding of the government of Tuvalu is surely required).
13-7 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
14. Public Relations (PR) and Educational Activities
14.1 Overview
Constructing a structure for beach maintenance is necessary to keep the beach in good condition. In other words, beach maintenance is important to make beach conservation sustainable as much as possible. Beach maintenance has two aspects: physical and non-physical aspects. Physical maintenance is a work related to materials such as refill of gravel and sand. On the other hand, non-physical maintenance is a thing related to people’s awareness or manner and this chapter focuses on how to improve this non-physical structure through PR and educational activities.
14.2 Setting of Performance Goals
As a first step to prepare appropriate PR and educational activity plan, problems on the relationship of public and beach were accessed and the main three problems are identified as follows:
➢ Lack of knowledge on appropriate coastal conservation measure ➢ Bad habits of dumping rubbish on the beach ➢ Lack of awareness that the beach is a public property
Based on these identified problems, the four performance goals to be acquired as a result of public relations and educational activities to the public are set as follows. The first three goals directly correspond to the three problems aforementioned. The fourth goal is set additionally to make effect of the activities more sustainable in the future.
< Performance Goals of Public Relations and Educational Activities>
1) The Tuvaluan people, not only in the Project area, but also outside of the Project area, become familiar with the purpose and outcome of the Project, especially in terms of environment and beach use aspects.
2) Public awareness on beach environment is developed so as not to dump rubbish on the beach and to join any voluntary activities to maintain the beach in good condition.
3) Public awareness on beach environment is developed so as not to do any illegal activities on the beach such as stealing of materials and construction of structures.
4) Young generations become interested in beach conservation and understand the importance of beach management.
14-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
14.3 Implementation of Public Relations and Educational Activities
Several PR and educational activities were implemented through the Project period to improve public awareness on beach conservation. The main activities are listed in Table 14.1 and the item (h), the first joint events, are summarized as the representative activities in this section. Table 14.1 PR Activities of Pre- and During- Construction (2015) Items of PR and Educational Involved Implementation Date Target* Activities Numbers From 2015 to 2017 more than ten (a) Radio Announcement Public N/A times in total Workshop on Beach Residents, (b) 12 Jun. and 21 Dec. 2015 20 Maintenance Stakeholders Residents (c) Beach Cleaning Event 1 Aug. 2015 150 Stakeholders (d) Singing Competition 10 Oct. 2015 Public 30 Tour during Students (e) 15 Oct., 5 and 11 Nov. 2015 100 Construction Period Island Chiefs (f) Drawing Competition 17 Nov. 2015 Students 30 Opening Ceremony of (g) 18 Dec. 2015 Stakeholders 70 the Beach First joint event of Week of 20 Jun.: Environmental environmental lessons, lessons (h) beach cleaning, and Students 800 29 Jun.: Beach cleaning event beach sports event 1 Jul. 2016: Beach sports festival (2016) Preparation of the (i) Aug. 2016 Stakeholders N/A Project PR Video Installation of the Project (j) 8 Sept. 2017 Beach users N/A Nameplate Second joint event of Weeks of 21st and 28th of Sept.: environmental lessons, Environmental lessons (k) beach cleaning, and Students 850 1 and 6 Sept.: Beach cleaning event beach sports event 8 Sept.: Beach sports event (2017) *Public : People in Funafuti and outer islands Residents : Residents who live behind and around the Project area Stakeholders : Funafuti Kaupule, government officials (MFATTEL, DOE, MPUI, Land & Survey Dept.) Students : Nauti primary school for first event and both Nauti and Seventh Day Adventist primary school for second Island Chiefs : Chiefs of the outer islands (Source: JICA Expert Team)
14-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
First Joint Event of Environmental Lessons, Beach Cleaning, and Beach Sports Festival in 2016 (Item (h)) Typical beach uses in Tuvalu were mainly for bathing in the morning and in the evening and boat parking and landing for local fishery industries. To make people recognize other ways of beach use, the beach sports festival for primary school was planned and implemented through the cooperation between the government and local communities. It was the first trial in Tuvalu to hold a sports festival and more than 800 people including the students’ family participated in the festival.
Important point is that this beach sports festival also aimed to create opportunities for participants in considering their roles in using the beach area safely and pleasantly. In this regard, the beach sports festival was implemented as part of the joint event which also included environmental lessons and beach cleaning to improve public awareness more effectively. The procedures are as follows: Firstly, to create an opportunity for school students to think about the importance of beach, classes on beach environment were held in cooperation with the teachers in the school. Secondly, to make participants understand and experience their roles in using the beach area pleasantly, a beach cleaning event was held a few days before the beach sports festival involving school students, teachers, community, and the government. Finally, the beach sports festival was held to make participants experience the pleasantness of playing on the beach. Figure 14.1 summarizes this stepwise sequence of activities, i.e., environmental education, beach cleaning event, and beach sports festival; and their objectives.
14-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Step-1: Environmental Education Purpose: To learn about the importance of beach environment
(Environmental lessons in the primary school taught by teachers using materials prepared by JET) Step-2: Beach Cleaning Event Purpose: To learn their roles in using beaches safely and pleasantly
(Beach cleaning event with senior students in the primary school) Step-3: Beach Sports Event Purpose: To learn the value of the beach by using it for play and other recreation.
(Beach sports event using the Project beach) Figure 14.1 Sequence of PR and Educational Activities Related to Beach Sports Festival (Source: JICA Expert Team)
14-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
14.4 Effects Confirmed by the Interview Survey and Observation
The outcomes of the activities in terms of public awareness and actual activities related to beach management were described as follows:
(1) Changes in public awareness on beach
Interview survey to residents was conducted in January 2017 to grasp the effects of the aforementioned public relations and educational activities quantitatively. The sample number was 62 and it was conducted not only near the Project site but also outside of the site and was done irrespective of age or sex to grasp the extent of the effect. At first, the survey results were quite positive because 92% of the respondents replied that they already know the Project beach. The following four changes in public awareness were confirmed from the interview survey results and changes can be summarized in Figure 14.2.
➢ Shift from protection-oriented awareness to that of beach use- and environment- consciousness
➢ Awareness on beach use and environment was developed for a wider range of people especially through the beach sports festival.
➢ Importance of beach maintenance was recognized due to improvements of public awareness on beach use.
➢ People firstly realized the effects of the beach nourishment and desired to extend the same measure to other coastal areas in Tuvalu.
Degree of awareness Very (2) High Protection
High (1)
Beach use and Environment Maintenance Low
Construction Construction Present Near Started Completed Future
Figure 14.2 Changes in Peoples’ Awareness on Beach through the Project Period (Source: JICA Expert Team)
14-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(2) Changes in activities related to beach management and beach use
The following three sections show changes in actual activities related to beach management and beach use:
➢ Community started periodic beach cleaning and beach environment was kept in good condition (Figure 14.3)
➢ Illegal activities on the beach had been prevented through multiple measures implemented by the community such as installation of signboard
➢ A new way of beach use became widespread among the public such as beach sports (Figure 14.4)
Figure 14.3 Periodic Beach Cleaning by Community (Source: JICA Expert Team)
(beach sports) (fishing from groins) Figure 14.4 New Types of Beach Use Spread to the Community (Source: JICA Expert Team)
14-6 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
15. Capacity Development and Knowledge Transfer
Programs related to capacity development and knowledge transfer implemented in the Project were summarized in the Table 15.1. Table 15.1 Programs Implemented for Capacity Development and Knowledge Transfer Name of program Timing Overview Technology exchange in Nov. The program was implemented to improve Mauritius on management and 2015 understanding on the know-how of management and maintenance of gravel beach maintenance of gravel beach by site visits and (for the Government officials discussions with relative government organizations and and Funafuti Kaupule) local communities in Mauritius.
The 4th Project Coordination Mar. Monitoring results and observed effects on Project Committee (PCC) 2016 beach after 3 months from completion were presented to stakeholders.
Training in Japan for coastal May The program was implemented to see both success and conservation measures and 2016 failure cases of coastal conservation measures by site management and maintenance visits in japan and to understand the importance of (for the Government officials careful planning and beach management and and Funafuti Kaupule) maintenance.
Seminar on the beach April The seminar was implemented to introduce nourishment (for the 2017 effectiveness of the beach nourishment that was Government officials and concluded from the monitoring results and to explain Funafuti Kaupule) the importance of beach management and maintenance in post construction period.
Technical transfer on 2016- Technologies, which were required for continuous monitoring 2017 monitoring, were transferred to relative stakeholders. Measurement of beach profile for DOLS Wave and current measurement for MET Drone application for DOE and Funafuti Kaupule
Knowledge transfer at GEF July The government officials, JET and JICA participated in workshop in Tonga 2017 the workshop with a purpose of knowledge transfer of the beach nourishment in Tuvalu to UNDP, SGP and officials from Pacific Islands countries.
Preparation and presentation of Oct. Two technical papers of the Project were prepared and technical papers in APAC 2017 presented in the Asian and Pacific Coasts 2017 to introduce technical characteristics of the Project.
(Source: JICA Expert Team)
15-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
16. Technical Guideline
16.1 Overview
The pilot scale project of the beach nourishment using coral gravel and sand was implemented in Tuvalu Country as the first trail of ecosystem-based and user-friendly type of coastal protection.
A lot of know-how and information as outcome of the Project were obtained through the Project, and such know-how and information are expected to serve as a useful reference not only to the related stakeholders in Tuvalu but also to other Pacific Island countries who are facing the similar coastal problem.
Further, JICA has implemented several coastal conservation projects applying beach nourishment in other countries.
From the above background, the obtained know-how and information through the Project and some information from other similar projects were summarized as the technical guideline on titled “Essential Points for Application of Beach Nourishment”
The main objective of this technical guideline is as follows.
➢ To understand the concept of ecosystem-based and user-friendly coastal conservation measure applied in Pacific Island countries
➢ To introduce the basic procedure and consideration for beach nourishment project as case based learning trough the Project in Tuvalu
16.2 Basic Policy
Basic policy of this technical guideline is as follows.
➢ This guideline is not only to the engineers who are engaged in the coastal work, but to wider stakeholders who are related and/or interested in the coastal problems (e.g. government officers, NGO members, donner officers, community members, etc.) in both Tuvalu and other Pacific Island Countries.
➢ This guideline focuses not only “hard point” as “coastal engineering”, “implementation of coastal measure” etc., but also “soft point” as “maintenance and management”, “consensus building”, “public relation and education”, etc.
➢ To achieve an effective expansion of knowledge, it was paid attention to keep “easy”, “simple” and “visibility”. From this policy, one topic was described in one page and not to put too much information for each topic.
16-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
16.3 Table of Contents
Contents of technical guideline are as follows. (Full set of the guidline is refer to the Supporting Report”.
Section 1: Concept of Beach Conservation, Basic Information of Beach Nourishment
1.1 Coastal Problems in Pacific Island Countries
1.2 Importance for Understanding of Long-term Historical Forming of Island and Original Own Function of Beach
1.3 Principle for Planning of Coastal Conservation Measure
1.4 Characteristics of Beach Nourishment
1.5 Example of Beach Nourishment (Based on JICA Project)
1.6 Chronology of Shore Protection Measure in Developed Countries
1.7 Stability of Beach Nourishment after Construction
1.8 Cost and Benefit for Beach Nourishment
Section 2: Planning and Design of Beach Nourishment
2.1 Essential for Layout Planning
2.2 Essential for Beach Profile Design
2.3 Supplementary Coastal Structures to Maintain Nourishment Material
2.4 Identification of Boundary Between Nourishment Area and Existing Property
2.5 Importance of Public Consultation on Planning and Design
Section 3: Construction
3.1 Considerations on Construction Planning for Beach Nourishment
3.2 Environment Monitoring during Construction
3.3 Points to Note on Construction Works
Section 4: Monitoring, Maintenance and Management
4.1 Purpose of Beach Monitoring
4.2 Basic Monitoring by Community and Residents
4.3 Advanced Monitoring by the Government
4.4 Beach Maintenance by Beach Cleaning
16-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
4.5 Rules on Beach Use
4.6 Adaptive Measure and Proposed Beach Management Structure
4.7 Importance of Public Relations and Educational Activities
4.8 PR & Educational Activities Implemented in the Project
4.9 Changes in Public Awareness on Beach through the Project
16-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
17. Future Development of Beach Nourishment Project
17.1 Overview
The Project is the first trial in applying the ecosystem-based and user-friendly type of coastal protection measure in the Pacific island countries, which is beach nourishment using gravel and sand, to recover the original image of the natural beach. Thus, it is required to clarify the level of understanding and get opinion for this new type of coastal protection measure to the government of Tuvalu, community, and Funafuti people.
Even though the government of Tuvalu and/or the public opinion of Tuvalu showed a positive request to apply the same type of protection measures, it is also required to clarify the feasibility for procurement of nourishment materials such as sand and gravel.
This chapter shows the feasibility for future development of same type of protection measures, beach nourishment in Tuvalu and other Pacific island countries.
17.2 Level of Understanding for Nourishment Based on Interview Survey
Interview survey was conducted to evaluate how a concept of beach nourishment had been well spread and made public through the Project. While comprehensive results of the survey are described in Chapter 15 in this report, results related to the level of understanding on beach nourishment are summarized in this section.
From these results, it is concluded that the concept of beach nourishment had been well recognized among the people in Funafuti and they understand the effect of the beach nourishment even this was quite a new coastal conservation measure applied in Tuvalu. As for the results, most of them have requested for the development of beach nourishment in other areas in Tuvalu as well.
17.3 Feasibility for Procurement of Nourishment Material
(1) Types of Nourishment and Required Materials
Several types of beach nourishment methods exist and there are several options of employed material for nourishment. Sand beach is the most popular in nourishment. However, gravel or combined gravel and sand beach are also employed depending on each site condition.
There are also several options for structure type of supplementary coastal structures such as rubble type, concrete block type, concrete type, flexible type (geo-bag, geo-tube, etc.). Even though there are several options; and required material is variable depending on selected type of nourishment and structure type as mentioned above, the procurement for gravel, sand, and armor rock are discussed in this chapter as main representative materials for the future expansion of the same type of coastal adaptation measure in Tuvalu.
17-1 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(2) Gravel
a) Possibility to obtain gravel from Funafuti Atoll
It was not allowed to extract significant quantity of gravel from land side for future full-scale projects considering the possibility of negative impact to the surrounding beach. However, it was found that certain amounts of gravel exist on the seabed at the channel, which is located on the west side of Funamanu Island, as a result of the diving survey in Phase-1. Even though further investigation is required, there is a possibility that this location will become one of potential borrow sites for gravel extraction to be utilized for future full-scale project.
There is another possibility to extract gravel from the seabed in the lagoon. Based on the experience for the borrow pit Project by New Zealand (NZ) Aid and following reclamation project by the government of Tuvalu , it was observed that some portion of gravel contained in dredged sand. Even though further investigation is necessary to identify the quantitative rate of contents of gravel, there is a possibility to obtain the gravel from the dredged sand.
b) Import from other country
In case that the possibility to procure the gravel in Tuvalu is low, another option is to import from other countries. Basically, it is difficult to obtain the natural produced coral gravel from other countries due to environmental issue as same as the Tuvalu case. Thus, the imported gravel will be a volcanic one or crushed rock from land quarry site. Considering the increase in transportation cost, it is better to import nearby country from Tuvalu. Even so, the material cost will significantly become high.
(3) Sand
The seabed of Funafuti Atoll consists of coral sand with some contents of coral gravel. Tuvalu country consists of five atolls and four islands. Basically, the seabed condition at the other atolls is also expected to be at the same situation as Funafuti Atoll. Thus, coral sand is only the material to be utilized as coastal protection measures.
However, the grain size of sand is very important for stability of nourished beach. Further detailed investigation is required to identify the quantity and quality of sand with certain accuracy.
In case that the dredging area is close to the beach and depth is shallow, the dredging activity may cause a negative impact to surrounding beach, namely, further beach erosion might be occurred. Thus, it is very important to select the dredging site taking into account the presumed impact to the beach. In general, the depth of dredging is recommended to be set more than 15 to 20 m. Beach monitoring at the surrounding coast is also required to assess the
17-2 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
impact after the dredging activity if the dredging area is close to the beach or shallow water area.
(4) Armor Rock
As Tuvalu Island was formed by accumulated coral gravel and sand, it is impossible to obtain armor rock with certain size and weight. Even if the construction site will be on the lagoon
side, where the wave condition is calm and the design wave height (H1/3 for 30-year return period) is about 1.6 m based on the design calculation in Phase-1 Stage, about 1 ton size of armor rock for rough shape is required to secure the stability of rubble type groin (refer to Progress Report). The only possibility to procure the armor rock is to import from outer countries.
According to the design standard for armor type of structure, the required stability weight for armor is significantly different between rough shaped armor and rounded one. It is recommended to apply the armor rock with rough shape for economical design.
17.4 Possibility for Implementation of Beach Nourishment Project in Tuvalu
(1) Basic Idea for Potential Project Area
The basic ideas to examine the implementation plan for beach nourishment project are described as below, taking into account the necessity and possibility of beach nourishment measure in Tuvalu Island based on the obtained information through the Project.
➢ Main target island for the implementation of coastal adaptation measure using beach nourishment may be Fongafale Island, which has been threatened by the risk of coastal disaster due to coastal erosion by anthropogenic land alternation and increase of environmental load due to rapid population growth in the recent ten years.
➢ Other coastal issues have been also identified on other islands, Nulufetau, Nanumea and Nanumaga in Tuvalu. However, the United Nations Development Programme (UNDP) has already implemented the coastal protection in Nulufetau, while Nanumea and Nanumaga have also covered by the “Tuvalu Climate Adaptation Project (TCAP)” as implemented project site. For this moment, it seems that there are no other sites that urgent remedy is required.
➢ Beaches on the ocean side of Fongafale Island were covered by natural gravel and this condition has been maintained until now because of no anthropogenic land alternation on the ocean side. Furthermore, no sandy beach exists on the ocean side ever since. Thus, the required and potential area for applying the beach nourishment measure might be the coastal area on the lagoon side.
17-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
➢ Two coastal projects have been undertaken in the central part of Fongafale Island, which are the “Pilot Gravel Beach Nourishment by JICA” and the “Reclamation and Nourishment Project by the government of Tuvalu”, as shown in Figure 17.1. Furthermore, the coastal area from the Funafuti Wharf to the south with approximately 1 km alongshore distance will be covered by the TCAP. On the other hand, serious coastal erosion problems have been identified on both further north and south coasts on the lagoon side with roughly 3 km and 1.5 km, respectively. The hinterland on these coasts are also highly utilized as residential and public area. From this, the potential area for future coastal adaptation using beach nourishment is assumed in these two coasts.
Figure 17.1 Existing and Potential Area for Beach Nourishment Project (Source: Google Earth Pro arranged by the JICA Expert Team)
(2) Expected Implementation Schedule
One ideal implementation schedule for the future potential project of beach nourishment in the next ten years is shown in Table. 17.1, taking into account the tentative schedule for the TCAP, which was presented in the inception meeting in August 2017. Even if it is difficult to say the expected funding body for this moment, it is suggested to consider the future image of coastal adaptation in Tuvalu to ensure to mitigate the coast against future risk on coastal disaster.
17-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
Table 17.1 Ideal Implementation Schedule for Beach Nourishment Project
Project Locatiion Planned Area Activity 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028
Coastal Assesment From the TCAP Funafuti Wharf to about 1 km Construction (by GCF) the south Maintenance & Management
Planning & Design From the about 3 km (Project A) Funafuti Wharf to Construction (assumed) the north Maintenance & Management
Planning & Design
South of about 1.5 km (Project B) Construction Fongafale (assumed) Maintenance & Management
(Source: JICA Expert Team)
17.5 Subject and Consideration Point
Based on the results of Section 17.2 and 17.3, the subject and consideration point for maintenance and management of pilot gravel beach project and future expansion of full-scale project for beach nourishment are summarized in this section.
(1) Maintenance and Management for Pilot Gravel Beach
Subject 1) Concrete adaptive measure for abnormal condition (possibility for drastic change of beach condition due to abnormal wave condition)
Almost two-year beach monitoring was conducted and characteristics of beach behavior for seasonal change and high wave condition have become clear. On the other hand, even though several high wave conditions were experienced, e.g., during Cyclone “Ula” in January 2016, Cyclone “Winston” in February 2016, extreme condition under combined abnormal wave and tide conditions has not been experienced. The maintenance work and procedure of the project beach as adaptive measure was also recommended and executed in the Project. However, the recommended maintenance was based on the limited monitoring period and not for abnormal external condition. Therefore, there is a possibility to require the different adaptive measures for abnormal external condition.
2) Maintaining basic understanding, procedure and taking realistic action of Kaupule and Funafuti communities on beach maintenance and management
Continuous beach maintenance and management has been undertaken for two years after the construction mainly by Funafuti Kaupule and the community, and successive results for community-based beach maintenance and management have been obtained. However, even
17-5 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
though the action on beach maintenance and management has been undertaken by Tuvaluan side through the Project, and they have committed to take action continuously after the Project, it is uncertain that they surely carried out or not. Especially, it is uncertain in case of after retirement of present members of Kaupule who have been related to the maintenance and management work in the Project. Because, the replaced new members might not be so familiar and capable to maintain the beach due to less experience on beach maintenance and management work.
3) Maintaining the required equipment for maintenance in Kaupule
Special equipment is not required for the beach maintenance work of the pilot gravel beach. Based on the experience of undertaking beach maintenance in the Project, it was realized that excavator and wheel loader were contributed mainly to the beach maintenance work. Kaupule has owned such two equipment, which were procured from the contractor after the completion of construction. However, several parts have already been damaged and it is not sure in securing of durability of the equipment. It is necessary to consider securing the equipment for continuous beach maintenance after the completion of the Project.
4) Securing sand for maintenance of the Project beach
As the monitoring result, total volume of filled sand has been decreased a little by continuous wave action, even though the beach could be maintained in stable condition. Stocked sand with roughly 80 m3 was employed for adaptive measure in September 2017 with acceptance of the government of Tuvalu. According to the information from the government of Tuvalu, the stocked sand will be mostly utilized in the maintenance of reclamation area (Elizabeth Park) and material for planned building construction. At this moment, there is no sufficient sand to be used for other purpose. From such current condition, it might be difficult to obtain the acceptance of the government of Tuvalu for the use of stocked sand in the next time for maintenance of the Project beach.
Consideration Point
1) Necessity of continuous monitoring by the Tuvaluan side and sharing of information of beach condition to related parties
The necessity to execute the adaptive measure after acting the abnormal external condition will be judged based on actual beach condition. Thus, the continuous beach monitoring carried out by the Tuvaluan side is strongly requested to know the relation between acting wave and tide condition and resulting beach change. Further, it is important to share such information to the related stakeholders in Tuvalu and other parties who are interested in the same coastal issue.
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2) Necessity to establish the “interactive activation structure” on beach maintenance and management between beach users and management side
It is necessary to establish an inevitable system on beach maintenance and management among related stakeholders both beach users (Funafuti people) and management side (Funafuti Kaupule and Tuvaluan government) in order to achieve the community-based beach maintenance and management. In the Phase-3 stage of the Project, the set of “organizing of community participated beach sports events” and “implementation of adaptive measure” was conducted for the purpose of achieving such structure on beach maintenance and management. Continuing such events based on strong request from the community is expected to lead the driving force to ensure the realization of community-based beach maintenance and management by Funafuti Kaupule sustainably maintaining their passion and motivation, even if the present members will be changed.
3) Consideration for procurement of required equipment for beach maintenance
It is hard to do such adaptive measure proposed in the Phase-3 stage of the Project without the excavator. Also, the condition of present excavator is getting worse due to damage of several parts. It is requested to consider the possibility of procurement of new excavator for maintenance work in the future.
4) Securing of sustainable sand stock through the planned coastal project
Sand for maintenance about the order of 100 m3/year is recommended to maintain the Project beach in good condition. This required quantity is very small from the existing volume of stocked sand. It is requested to the government of Tuvalu the use of small amount of sand for the maintenance of the Project beach in the future.
On the other hand, the big-scale coastal protection project, which is the “Tuvalu Coastal Adaptation Project (TCAP)” using the Green Climate Fund (GCF) will commence in 2018. The provision of new sand stock into the TCAP is recommended to secure the sand for beach maintenance not only for this pilot project, but also for future full-scale project for beach nourishment.
(2) Expansion of Full-scale Project for Beach Nourishment
Subject
1) Uncertainty for provision of large amount of coral gravel as full-scale project
As presented in Section 17.3, there are two possibilities to obtain gravel in Tuvalu, which are obtaining from the deep channel on the west side of Funamanu Island (Case-1) and obtaining from the seabed on the lagoon (Case-2). However, there is the difficulty for the construction method in Case-1 for taking gravel from the deep seabed under existence of swell wave and
17-7 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
strong tidal current. Also, there is no sufficient information about the potential volume of gravel for both cases at this moment.
2) Economical method to secure sand stock for maintenance
If the sand for maintenance will be procured in different timing from the initial construction in Tuvalu, the newly mobilized dredger is required and it causes high construction cost. Basically, it is required to stock sand, which will be utilized as future maintenance for nourishment during the initial construction.
3) Declaration for intention of public opinion for demand of nourishment as coastal protection measures
The Funafuti people and the government of Tuvalu have realized the effect and advantage of beach nourishment method through the Project. However, it seems that the common opinion of desirable coastal protection measure in Tuvalu is still “hard structure measures”, such as revetment, seawall, breakwater, etc. One of the reasons might be that; this was based on their long-term understanding in Tuvalu. On the other hand, the beach nourishment method was just newly applied in the Project and Tuvalu people have no experience of this until now. Even though it has been tried to share and expand the knowledge for ecosystem-based and user-friendly type of coastal protection measure, it seems that it is still not sufficient to change their mind. As a result, there is a possibility to apply the hard structure measures without sufficient consideration for the use of coastal area and hinterland, difference of wave condition between the lagoon and ocean side, environmental impact to surrounding beach, etc.
4) Reality of sustainable beach management and maintenance in Tuvalu for full scale project
Ongoing community-based beach maintenance and management is for the limited pilot project area with 180 m alongshore distance. On the other hand, the required area of beach maintenance and management for full-scale project will increase drastically. The expansion of the project area might induce the difficulty of community-based beach maintenance work.
Consideration Point
1) Necessity of further study for potential volume, construction method, and cost for gravel
Further study is required to identify the potential volume of gravel for two possibilities, which are obtaining from the deep channel on the west side of Funamanu Island (Case-1) and obtaining from the seabed on the lagoon (Case-2). Also, the construction method especially for Case-1 is required taking into account the wave and current condition on site. Finally, the cost shall be compared for both imported and procured case in Tuvalu.
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2) Implementation of sand stock and establishment of management system for sand stock
It is important to consider securing sand stock while the big dredger stay in Tuvalu for large-scale coastal protection project, such as TCAP. Also, appropriate management of stocked sand is required taking into account the future plan for the use of sand not only for the beach protection project but also for other purpose.
3) Necessity of continuous knowledge transfer and PR activity
The understanding and knowledge for beach nourishment is still not enough to Tuvalu people. Continuous knowledge transfer in Tuvalu is requested to be considered, for example, holding the seminar, site visit to beach nourishment project in other countries, etc. PR activity to show the difference of function from other hard structure type protection is also requested to be considered to expand the information. Conducting beach sports event annually is one of the effective PR activities.
17-9 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
18. Conclusion and Suggestion
18.1 Conclusion
(1) Effectivity and validity of beach nourishment using coral gravel and sand were proved
The beach nourishment using coral gravel and sand was proposed as the first trial of ecosystem-based and user-friendly type of coastal protection measure in Tuvalu, and applied to the central area on the lagoon side (Tausoalima) in Fongafale Island. Based on a two-year monitoring result, it was proven that the required three functions, which are “protection function”, “beach use”, and “coastal environment”, as ecosystem-based and user-friendly type of coastal protection measure could be fulfilled. There are no other protection measures to fulfill such three functions except for the beach nourishment.
(2) No adverse impact on the surrounding coasts at both the gravel borrow site and the Project site was identified based on the monitoring result
The influence on surrounding beach due to construction activities at the gravel borrow site (Funamanu and Papaelise islands) and the Project site was monitored for two years by visual checking, comparison of beach profile, and aerial photo. The result showed that no adverse impact on the surrounding coasts at both sites was identified.
(3) Community-based beach management was successfully established
It was realized that the initial constructed beach was flexible due to wave action. Thus, beach maintenance and management is important in order to maintain a comfortable condition especially on “beach use”. As the Project beach is utilized as public beach for Funafuti people, who are the main beach users, they have frequent opportunities to identify the beach condition on a timely manner. From this, it was realized that “community-based beach management” not the “government-based beach management” is necessary to maintain its sustainability. To achieve this, beach management consists of “beach cleaning”, “self-control for beach use”, and “executing adaptive measure for beach maintenance”, was carried out by Funafuti Kaupule with public participation. The result showed that the community-based beach management was effective and realistic for sustainable beach management with Tuvalu ownership.
(4) Adaptive management based on monitoring result was implemented
It was proven that conducting appropriate adaptive measures after initial construction was both effective in the improvement of the beach condition for beach use and enhancement of
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the life period of the beach. To ensure action by the community in Tuvalu will be sustainably done, the proposed adaptive measure shall be “simple and easy with low technology only”. Furthermore, the “integrated inevitable system”, which consists of “execution of adaptive measure”, “active use for events using improved beach” and “educational activity” as one set activity, will be required to accelerate public participation in beach maintenance and awareness of responsibility on beach maintenance and management by the local government (Funafuti Kaupule), and finally to ensure the sustainable execution of future community-based beach management by the Tuvaluan side.
(5) Public awareness on beach conservation was significantly improved
Improving public awareness on beach environment is one of the urgent issues to be accomplished in terms of beach management because it was directly related to people’s behavior on the beach such as dumping rubbish, illegal activities, and so on. Several public relation (PR) and education activities were applied through the Project for this purpose. As presented in Chapter 14 from the interview survey results, it was confirmed that public awareness on the beach, especially for beach environment and beach use, was significantly improved due to PR and educational activities and these contributed to maintain the beach area in good condition for almost two years after the implementation.
(6) Capacity of stakeholders on beach nourishment was developed through the Project
Since the Project goes through a whole process on coastal conservation, which are investigation, planning, design, construction, monitoring, and adaptive management, knowledge on coastal conservation of the counterpart (C/P) had been developed with the Project progress. In addition, several programs such as technical exchange in Mauritius and training in Japan contributed in the improvement of stakeholders’ understanding on beach nourishment through the lessons learned from other countries.
18.2 Suggestion
For Beach Maintenance and Management
(1) “Interactive Activation Structure” is requested to establish a sustainable community-based beach management by the Tuvaluan side
As mentioned above, continuous execution based on the “interactive activation structure”, consists of “execution of adaptive measure”, “active use for events using improved beach”, and “educational activity” was requested to ensure a sustainable execution of community-based beach management by the Tuvaluan side. Beach sports event was one of
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the effective approaches to enhance both people’s awareness on beach environment and maintenance and the responsibility of Funafuti Kaupule on beach maintenance and management. It is expected that Funafuti people and primary schools continue to organize such event using the beach annually, and coordinate with Funafuti Kauple and the Government of Tuvaluan. This will be a driving force to ensure the sustainability and realization of community-based beach maintenance and management by Funafuti Kaupule maintaining their passion and motivation, even if the present members of Funafuti Kaupule will be changed.
(2) Procurement of the equipment for beach maintenance will be considered
It is also necessary to consider maintaining the equipment for beach maintenance. It was proven that the excavator was useful in implementing the proposed adaptive measure to take gravel from the foreshore area and return to the original backshore area. It is recommended to consider the procurement of equipment for beach maintenance in the near future by the Japan International Cooperation Agency (JICA) or other donors.
(3) Securing of sand provision for maintenance is requested by the Tuvaluan government for the first two to three years.
In the monitoring result, the filled sand moved to the south; and the total volume of sand has been decreased a little by continuous wave action, even though the beach could be maintained in stable condition. It is preferable to re-fill of the sand as one of the adaptive measures as an undertaking in the Phase 3 of the Project. As the required volume is very small about the order of 100 m3/year based on these monitoring result, it is requested to the Tuvaluan government for the use of such small amount of sand in the maintenance of the Project beach for the first two to three years until the next opportunity comes to stock sand.
(4) Taking photo continuously from fix point after the Project is requested
Continuous monitoring of the beach is important to know the beach behavior for both normal and extreme wave conditions and to plan for suitable adaptation measure as required. Beach profile monitoring was carried out throughout the Project as well as taking photos from the fix point to know the beach behavior in detail. However, it might be difficult to enforce such complicated monitoring on the Tuvaluan side from now. Taking into account the possibility and sustainability for implementation of beach monitoring by the Tuvaluan side, taking photo from the fix point will be feasible. And if possible, checking the backshore width at several representative lines is also recommended to be carried out together with taking photo.
18-3 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(5) Continuous wave observation is effective for beach monitoring and other purpose
Accumulation of continuous wave and tide observation data will become very useful not only for beach monitoring but also for planning of future coastal and marine projects and other meteorological purpose. The bottom-mount type wave-current meter (Wave Hunter) was handed over to the Tuvalu Meteorological Service. It is strongly recommended to carry out the wave observation continuously by Tuvalu Met Office.
For Future Expansion of Beach Nourishment
(1) It is recommended to apply ecosystem-based and user-friendly type of protection measure on the lagoon side
It is important to keep the concept of “selection of right protection measure at the right place” in coastal adaptation. In case that the targeted project area is located at the residence or public area where people commonly gather, it shall be considered three functions on the selection of coastal protection measures, which are “protection function”, “beach use”, and “coastal environment”. The request to consider such three points was also shown in the result of the interview survey with Tuvalu people. From this point of view, it is basically recommended to adopt the same type of ecosystem-based and user-friendly type of protection measure, “beach nourishment” on the lagoon side, where coastal area is highly utilized as the residence and public area. The Tuvalu Coastal Adaptation Project (TCAP) is planned to implement at the area of lagoon side from the north of the Project site to Funafuti wharf with approximately 1.0 km. It is expected to select the ecosystem-based and user-friendly type of protection measure at the Project area.
(2) Holding of beach sports event as annual event is strongly recommended
Even though the understanding of beach nourishment for Tuvalu people could be enhanced by implementation of the Project, the present situation is just to stand in the same field as other coastal protection measures. Continuous PR and promotion activity to enhance the knowledge and experience for this ecosystem-based and user-friendly type of coastal protection measure are requested. As the result of the Project, it was realized that the conducted beach sports event greatly contributed on public relation (PR) effect as well as in enriching the understanding for beach nourishment through the actual activity on the beach. Thus, it is strongly recommended to hold the same beach sports event as an annual school event.
18-4 Project for Pilot Gravel Beach Nourishment against Coastal Disaster on Fongafale Island in Tuvalu Summary of Final Report
(3) Implementation of future sand stock is requested to consider in full-scale coastal project and establishment of a management plan for sand stock is requested
To consider the future expansion of beach nourishment measure in Tuvalu, there are mainly two subjects for implementation, that is “securing of gravel for full-scale project” and “securing of sand for future maintenance”. Even though a further study is required to ensure the potential volume of gravel as mentioned in Chapter 17, there is another option to use only sand. However, as sand is easier to move due to wave action, appropriate design including supplementary coastal structures is requested based on the detailed study for drift of sand. Securing of sand for future maintenance is requested to maintain the nourished beach sustainably. Preparing of management plan for sand stock is required taking into account the future plan for the use of sand not only for the beach protection project but also for other purpose. It is also necessary to consider the appropriate timing for the implementation of sand stock taking into account the cost efficiency. At least, sand stock is recommended to implement during the full-scale coastal project such as Tuvalu Climate Adaptive Project (TCAP). However, attention will be on the selection of the location of sand mining area so as not to cause new coastal erosion problems.
(4) Technical guideline is expected as reference for the appropriate selection of coastal adaptation measures and its implementation
The technical guideline for beach nourishment was prepared as one of the results of the Project. This guideline shows the basic idea for consideration on the selection of coastal adaptation measure and for planning and design of beach nourishment. It is expected to refer this guideline to the persons who are related to planning, design, and implementation of the coastal project in Tuvalu and other Pacific Island countries.
(5) It is recommended to take opportunities to learn about coastal conservation from other countries.
To learn from case examples in other countries, such as technical exchange in Mauritius and training in Japan implemented in the Project, it is very useful to improve the understanding on planning and design of coastal conservation measures. Therefore, it is recommended, especially for key personnel who will be in charge of coastal conservation in the government and Kaupule, to keep taking opportunities to learn from other countries as much as possible. One opportunity can be the JICA’s knowledge co-creation program (group and region) on coastal conservation, which will be implemented this coming two years, 2018 and 2019 respectively.
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