EXISTING CONDITIONS - JICAopen_jicareport.jica.go.jp/pdf/11709755_01.pdf · japan international...

JAPAN INTERNATIONAL COOPERATION AGENCY THE GOVERNMENT OF THE REPUBLIC OF INDONESIA THE STUDY ON FLOOD CONTROL AND WATER MANAGEMENT

IN LIMBOTO-BOLANGO-BONE BASIN IN THE REPUBLIC OF INDONESIA

FINAL REPORT

VOLUME-III SUPPORTING REPORT: PART-A

EXISTING CONDITIONS

DECEMBER 2002

NIKKEN CONSULTANTS, INC. AND

NIPPON KOEI CO., LTD.

THE STUDY ON FLOOD CONTROL AND WATER MANAGEMENT IN

LIMBOTO-BOLANGO-BONE BASIN

FINAL REPORT

LIST OF REPORTS

VOLUME-I SUMMARY VOLUME-II MAIN REPORT VOLUME-III SUPPORTING REPORT: PART-A

EXISTING CONDITIONS

VOLUME-IV SUPPORTING REPORT: PART-B FLOOD MITIGATION MASTER PLAN

VOLUME-V SUPPORTING REPORT: PART-C FEASIBILITY STUDY FOR PRIOROTY PROJECTS

VOLUME-VI SUPPORTING REPORT: PART-D EXECUTION OF STUDY

VOLUME-VII DATA BOOK VOLUME-VIII DRAWINGS The costs are estimated based on the price and average exchange rate in November 2001. The average exchange rate is assumed as follows:

US$ 1.00 = Rp.9,600 ¥ 1 = Rp.77.4

Part-A: Existing Conditions

A-i

THE STUDY ON FLOOD CONTROL AND WATER MANAGEMENT IN

LIMBOTO-BOLANGO-BONE BASIN

FINAL REPORT VOLUME-III SUPPORTING REPORT: PART- A

EXISTING CONDITIONS

Table of Contents Glossary A1. TOPOGRAPHY AND GEOLOGY............................................................A1-1 A1.1 Topography ................................................................................................A1-1 A1.2 Geology .....................................................................................................A1-2 A1.3 Geotechnical Conditions ............................................................................A1-4 A2. HYDROLO-METEOROLOGY.................................................................A2-1 A2.1 Overview of Basin and River System ........................................................A2-1 A2.2 Review of Previous Hydrological Studies .................................................A2-2 A2.3 Characteristics of Rainfall and Runoff ......................................................A2-4

A2.3.1 Climate ........................................................................................A2-4 A2.3.2 Rainfall .......................................................................................A2-5 A2.3.3 Runoff .........................................................................................A2-7

A2.4 Existing Hydro-Meteorological Observatory ............................................A2-9 A2.4.1 Rainfall Observation ...................................................................A2-9 A2.4.2 Flow Measurement ...................................................................A2-10 A2.4.3 Availability of Data ...................................................................A2-11

A3. RIVER BASIN AND CHANNEL...............................................................A3-1 A3.1 River Basin ................................................................................................A3-1 A3.2 Principal Channel Features ........................................................................A3-2 A3.3 Flood and Sediment Disasters ...................................................................A3-3


A-ii

A4. NATURAL ENVIRONMENT ....................................................................A4-1 A4.1 Existing Natural Conditions ......................................................................A4-1

A4.1.1 Terrestrial Flora and Fauna ........................................................A4-1 A4.1.2 Aquatic Ecology of Lake Limboto ............................................A4-4 A4.1.3 Endemic and Protected Species .................................................A4-6 A4.1.4 Forest .........................................................................................A4-7 A4.1.5 Physical Conditions of Lake Limboto .....................................A4-10 A4.1.6 Groundwater ............................................................................A4-10 A4.1.7 Water Quality ...........................................................................A4-11 A4.1.8 Other Environmental Issues ....................................................A4-22

A4.2 Legislations for Natural Environmental Conservation ............................A4-23 A4.3 Procedures for Environmental Impact Assessment .................................A4-24 A4.4 NGOs and Other Organizations Acting in Study Area ............................A4-26 A5. SOCIAL ENVIRONMENT ........................................................................A5-1 A5.1 Present Social Conditions ..........................................................................A5-1 A5.2 Land Acquisition Procedures and Compensation ......................................A5-3 A5.3 NGOs and Other Organizations Active in Study Area ..............................A5-5 A5.4 Social Survey .............................................................................................A5-6 A6. SOCIO-ECONOMY....................................................................................A6-1 A6.1 Administration ...........................................................................................A6-1 A6.2 Population ..................................................................................................A6-2

A6.2.1 Basin Population ........................................................................A6-2 A6.2.2 Labor Force ...............................................................................A6-4 A6.2.3 Housing Conditions ...................................................................A6-5 A6.2.4 Poverty Conditions ....................................................................A6-6 A6.2.5 Ethnic Groups ............................................................................A6-7

A6.3 National and Regional Accounts ...............................................................A6-8 A6.3.1 Macro Economy .........................................................................A6-8 A6.3.2 Balance of Payment ..................................................................A6-11 A6.3.3 External Debt and Outstanding .................................................A6-13

A6.4 Economic Profiles ....................................................................................A6-14 A6.4.1 Agriculture Sector .....................................................................A6-14


A-iii

A6.4.2 Industry Sector ..........................................................................A6-16 A6.4.3 Services Sector .........................................................................A6-18 A6.4.4 Family Income and Expenditure ...............................................A6-19 A6.4.5 Price Indices .............................................................................A6-19 A6.4.6 Foreign Exchange Rate .............................................................A6-20

A6.5 Infrastructures ..........................................................................................A6-20 A6.5.1 Educational Facility ..................................................................A6-20 A6.5.2 Medical Facility ........................................................................A6-21 A6.5.3 Road ..........................................................................................A6-22 A6.5.4 Water Supply ............................................................................A6-22 A6.5.5 Electrification ...........................................................................A6-22 A6.5.6 Communications .......................................................................A6-23

A6.6 Public Finance .........................................................................................A6-23 A6.6.1 Natural Revenue and Expenditure ............................................A6-23 A6.6.2 Provincial Revenue and Expenditure .......................................A6-24 A6.6.3 Revenue and Expenditure of Local Governments ....................A6-25 A6.6.4 National Expenditure for Flood Control Project ......................A6-26

A6.7 Development Plans ..................................................................................A6-27 A6.7.1 Natural Development Plan ........................................................A6-27 A6.7.2 Long-Term Development Plan .................................................A6-28

A6.8 Projection of Future Socio-Economic Framework ..................................A6-29 A6.8.1 Population Projection ................................................................A6-29 A6.8.2 GDP and GRDP Projection .......................................................A6-30 A6.8.3 Public Expenditure for Flood Control ......................................A6-31

A7. ORGANIZATION AND INSTITUTION ..................................................A7-1 A7.1 Existing Organizational Setup ...................................................................A7-1 A7.2 Establishment of Gorontalo Province ......................................................A7-18 A7.3 Decentralization Policy ............................................................................A7-19 A7.4 Legal Aspect ............................................................................................A7-24 A8. REVIEW OF PREVIOUS STUDIES AND PLANS .................................A8-1 A8.1 LBB Basin Water Management Master Plan .............................................A8-1 A8.2 Drainage Master Plan of Gorontalo City ...................................................A8-3


A-iv

LIST OF TABLES Table A1.2.1 Geological Stratigraphy of North Sulawesi...................................................A1-9 A2.4.1 Rainfall Data Available for Study................................................................A2-13 A2.4.2 Runoff Data Available for Study .................................................................A2-14 A3.2.1 Characteristics of Existing River Channel.....................................................A3-5 A4.1.1 List of Flora Found in Lowland of Gorontalo Province..............................A4-29 A4.1.2 Urban Vegetation (Crops) Found during Field Reconnaissance in

Gorontalo .....................................................................................................A4-30 A4.1.3 List of Macrophytes.....................................................................................A4-31 A4.1.4 Impacts of Aquatic Macrophytes.................................................................A4-31 A4.1.5 Fish Species reported in Lake Limboto.......................................................A4-32 A4.1.6 Recorded Fish Species during Field Reconnaissance(on Aug 8th,2001) ....A4-32 A4.1.7 Result of Market Survey (on July 28th and Aug 9th,2001).........................A4-33 A4.1.8 Protected Species of Flora and Fauna in North Sulawesi............................A4-34 A4.1.9 List of Conservation Forest in LBB Watershed...........................................A4-36 A4.1.10 Occurrence of Groundwater and Productivity of Aquifer ...........................A4-36 A4.1.11 Average Recharge Coefficient in LBB Areas ..............................................A4-37 A4.1.12 Annual Groundwater Recharge in Limboto-Bolango-Bone Watershed ......A4-38 A4.1.13 Groundwater Balance in Limboto-Bolango-Bone.......................................A4-38 A4.1.14 Lake Limboto Water Quality Data in December 1977................................A4-38 A4.1.15 Laboratory Analysis of Some Water Quality Parameters ............................A4-39 A4.1.16 Summary of Water Quality (in September 2001) ........................................A4-40 A4.1.17 Summary of Water Quality (in December 2001).........................................A4-41 A4.1.18 Summary of Bottom Sediment (in September 2001) ..................................A4-42 A4.2.1 List of Law, Decree, Regulations on Natural Environment ........................A4-43 A4.2.2 Water Quality Criteria .................................................................................A4-44 A4.3.1 List of Law and Regulations, and Technical Guidelines on Environment

Impact Assessment ....................................................................................A4-46 A4.4.1 List of NGOS on Environment in Kabupaten Gorontalo ............................A4-47 A5.1.1 Population of Study Area by Kecamatan.......................................................A5-8 A5.1.2 Population of Study Area by Village .............................................................A5-9 A5.1.3 Number of Villages Which Have Social Institutions (by Type of

Institution) ...................................................................................................A5-14 A5.2.1 Procedure for Land Acquisition...................................................................A5-15 A5.3.1 Number of Youth Associations by Classification ........................................A5-16 A5.3.2 List of NGO Active in Study Area...............................................................A5-17


A-v

A5.4.1 Flood Incidents in Gorontalo Province........................................................A5-20 A5.4.2 Social Survey Sites by Kota/Kecamatan .....................................................A5-21 A5.4.3 Location of Social Survey Sites by Rivers/Lake .........................................A5-21 A6.2.1 Census Population and Labor Force in Indonesia, Propinsi Sulawesi

Utara, Kabupaten Gorontalo and Kota Gorontalo: 1980, 1990 and 2000 .....................................................................................................................A6-33

A6.2.2 Population Growth by Kecamatan Related to LBB Basin: 1980, 1990 and 2000 ......................................................................................................A6-34

A6.2.3 Population Density and Average Family Size in LBB Basin: 2000 ........A6-35 A6.2.4 Number of Gainful Workers in 15 Years Old and Over By Sector: 1990

and 1999 ..................................................................................................A6-36 A6.2.5 Characteristics of Housing Unit in Gorontalo: 1990 Census ..................A6-37 A6.2.6 Sanitary Conditions of Housing Unit in Gorontalo: 1990 Census ..........A6-38 A6.2.7 Energy Conditions of Housing Unit in Gorontalo: 1990 Census ............A6-39 A6.2.8 Poverty Conditions in Sulawesi Utara and Indonesia: 1996 and 1999 ...A6-40 A6.2.9 Welfare Family of Lower Degree in LBB Basin: 2000...............................A6-41 A6.2.10 Population by Ethnic Group in LBB Basin: 2000 .......................................A6-42 A6.2.11 Population by Religion in LBB Basin: 1999...............................................A6-43 A6.3.1 Gross Regional Domestic Product by Economic Sector at Current

Prices: 1994-2000 in Indonesia and Sulawesi Utara ...............................A6-44 A6.3.2 Gross Regional Domestic Product by Economic Sector at Current

Prices: 1994-2000 in Kabupaten/Kota Gorontalo ...................................A6-45 A6.3.3 Percentage Distribution of GRDP by Economic Sector: 1994-2000 .......A6-46 A6.3.4 GRDP per Capita: 1994-2000 ..................................................................A6-46 A6.3.5 Gross Regional Domestic Product by Economic Sector at 1993

Constant Prices: 1994-2000 in Indonesia and Sulawesi Utara ................A6-47 A6.3.6 Gross Regional Domestic Product by Economic Sector at 1993

Constant Prices: 1994-2000 in Kabupaten/Kota Gorontalo ....................A6-48 A6.3.7 Real Growth of GRDP by Economic Sector: 1994-2000 ........................A6-49 A6.3.8 Real Growth of GRDP per Capita: 1994-2000 ........................................A6-49 A6.3.9 Exports and Imports by Major Commodity Group: 1996-2000..................A6-50 A6.3.10 Exports and Imports by Country: 1996-2000..............................................A6-51 A6.3.11 Balance of Payments: 1995/1996-1999/2000 ..........................................A6-52 A6.3.12 Official Development Assistance: 1995-1999 .........................................A6-53 A6.3.13 External Debt: 1994-1999 .......................................................................A6-54 A6.4.1 Production of Major Crops: 1997-1999 ..................................................A6-55 A6.4.2 Production of Food Crops in LBB Basin: 1999 ......................................A6-56


A-vi

A6.4.3 Production of Fruits and Cash Crops in LBB Basin: 1999 .....................A6-57 A6.4.4 Distribution of Manufacturing Establishments in Kabupaten Gorontalo:

1999 .........................................................................................................A6-58 A6.4.5 Performance of Industrial Establishments by Scale of Industry in

Indonesia: 1997 - 2000 ............................................................................A6-59 A6.4.6 Management Indices of Large and Medium Scale Industrial

Establishments in Provinsi Gorontalo: 2000 ...........................................A6-60 A6.4.7 Number of Services Establishments in Kota and Kecamatan Related to

Flood Prone Areas in LBB Basin: 2000 ..................................................A6-61 A6.4.8 Average Monthly per Capita Expenditure in Propinsi Sulawesi Utara:

1999 .........................................................................................................A6-62 A6.4.9 Consumer Price Index and Wholesale Price Index: 1993-2001 ..............A6-63 A6.4.10 Foreign Exchange Rate of Rupiah per US Dollar at End of Period:

1993-2002 ................................................................................................A6-64 A6.5.1 Number of Schools and Enrollments in Kota and Kecamatan Related to

Flood Prone Areas in LBB Basin: 2000 ..................................................A6-65 A6.5.2 Number of Medical Facilities in Kota and Kecamatan Related to Flood

Prone Areas in LBB Basin: 2000 .............................................................A6-66 A6.5.3 Inventory of Road by System and by Surface Type in Kota and

Kecamatan Related to Flood Prone Areas in LBB Basin: 2000 ..............A6-67 A6.5.4 Inventory of Communication System in Kota and Kecamatan Related to

Flood Prone Areas in LBB Basin: 2000 ..................................................A6-68 A6.6.1 Actual Revenue and Expenditure of National Government:

1995/1996-1999/2000 ..............................................................................A6-69 A6.6.2 Budget of National Government: 1995/96-1999/2000 ............................A6-70 A6.6.3 Inventory of National Development Projects in Sulawesi Utara:

1999/2000 ................................................................................................A6-71 A6.6.4 Expenditure for Flood Control in Propinsi Sulawesi Utara:

1996/97-1999/2000 ..................................................................................A6-72 A6.6.5 Project Activity for Flood Control in Gorontalo (LBB) ..........................A6-73 A6.6.6 Actual Revenue and Expenditure of Local Governments: 1997/98 ........A6-74 A6.6.7 Actual Revenue and Expenditure of Kabupaten Gorontalo:

1995/96-1999/2000 ..................................................................................A6-75 A6.8.1 Population and GRDP Projection: 2000 - 2020 .........................................A6-76 A6.8.2 Projection of Investment for Flood Control Schemes in Gorontalo

Province: 2005 - 2020 ...............................................................................A6-77 A7.1.1 Area and Population in Gorontalo Province................................................A7-25


A-vii

A7.1.2 Administrative Features of Kota Gorontalo ................................................A7-25 A7.1.3 Household and Population of Kabupaten Gorontalo...................................A7-25 A7.3.1 Local Government Staff in Gorontalo Province..........................................A7-26 A7.3.2 Regional Revenue Based on Law No.25/1999............................................A7-27 A7.3.3 Actual Revenue of Kabupaten Gorontalo (TA, 1998 / 1999 and 1999 /

2000)............................................................................................................A7-28 A7.3.4 Actual Budget of Kabupaten Gorontalo (TA, 1998 / 1999 and 1999 /

2000)............................................................................................................A7-28 A7.3.5 Regional Income and budget for Public Work O&M in Gorontalo

Province .......................................................................................................A7-29 A7.3.6 Activity of Flood Control in LBB-River Basin Gorontalo Province 2002 .A7-30 A7.4.1 Major Regulations Related to Flood Mitigation..........................................A7-31 A8.1.1 Initiatives for Water Management Master Plan .............................................A8-5


A-viii

LIST OF FIGURES Figure A1.1.1 Topography of Study Area...........................................................................A1-10 A1.2.1 Geological Map of Study Area ....................................................................A1-11 A1.2.2 Schematic Geological Profile of Study Area ...............................................A1-12 A1.3.1 Location of Drilling Holes...........................................................................A1-13 A1.3.2 Geological Map of Toheti-Dehua Dam Site ................................................A1-15 A1.3.3 Geological Profile of Toheti-Dehua Dam Site.............................................A1-16 A1.3.4 Geological Map of Kayu Merah Dam Site..................................................A1-17 A1.3.5 Geological Profile of Kayu Merah Dam Site ..............................................A1-18 A2.3.1 Meteorological Conditions ..........................................................................A2-15 A2.3.2 Monthly Discharges.....................................................................................A2-16 A2.4.1 Location of Hydrological Stations in LBB Basin........................................A2-17 A3.1.1 River Basin Boundaries .................................................................................A3-6 A3.1.2 Overall Longitudinal Profile: Bone-Bolango River System .........................A3-7 A3.1.3 Overall Longitudinal Profile: Lake Limboto System....................................A3-8 A3.1.4 Administrative Boundaries of LBB Basin.....................................................A3-9 A3.2.1 River System in Plain Area..........................................................................A3-10 A3.2.2 Channel Characteristics ...............................................................................A3-11 A3.3.1 Frequently Inundated Areas.........................................................................A3-16 A4.1.1 Forest Classification by Function ................................................................A4-48 A4.1.2 Forest Classification in Study Area .............................................................A4-49 A4.1.3 Investigation Sites for Water Quality and Bottom-Sediment ......................A4-50 A4.2.1 Legislative Structure in Indonesia ...............................................................A4-51 A4.3.1 Procedural Flow of Environmental Impact Assessment..............................A4-52 A5.4.1 Location of Villages Selected for Social Survey .........................................A5-22 A6.1.1 Administrative Boundaries of LBB Basin ...............................................A6-78 A7.1.1 Organizational Structure of KIMPRASWIL ...............................................A7-36 A7.1.2 Organizational Structure of DGWR ............................................................A7-37 A7.1.3 Institutional Organization of Gorontalo Province .....................................A7-38 A7.1.4 Organization of Dinas PU/Kimpraswil Gorontalo Province .......................A7-39 A7.1.5 Organization of Flood Control and Coastal Prevention Gorontalo

Province .....................................................................................................A7-40 A7.1.6 Organization Scheme of Flood Control Region I, Dinas PU Kimpraswil...A7-41 A7.1.7 Organization of Dinas PU Kota Gorontalo..................................................A7-42 A7.1.8 Organization of Dinas PU-Praswil Kabupaten Gorontalo...........................A7-43 A7.1.9 Organization Structure of Flood Control Project in Kabupaten


A-ix

Gorontalo .....................................................................................................A7-44 A7.1.10 Organization of Dinas Sumber Daya Air, North Slawesi Province.............A7-45 A7.1.11 Organization of Water User’s Association (WUA) .....................................A7-46 A7.3.1 Suggested Organization of Dinas SDA Kabupaten/Kota Gorontalo ...........A7-47 A8.2.1 Flood and Land Slide Suffering Areas in Gorontalo City .............................A8-7

GLOSSARY

G-i

GLOSSARY

(ENGLISH ABBREVIATION)

ADB Badan Pembangunan Asia Asian Development Bank

ASTM American Standards for Testing Materials

BCR, B/C Rasio Harga dan Keuntungan Benefit Cost Ratio

BOD Biochemical Oxygen Demand

CEA Badan Pelaksana Kanada Canadian Executing Agency

CIDA Badan Penyandang Dana Kanada Canadian International Development Agency

COD Chemical Oxygen Demand

DD, D/D Disain Teknis/Rencana Teknis Detailed Design

DGWR Direktorat Jenderal Sumber Daya Air Directorate General of Water Resources

DGWRD Direktorat Jenderal Pengairan Dir. General of Water Resources Development

DO Dissolved Oxygen

EIA Analisa/Penelitian Lingkungan Environmental Impact Assessment

EIRR Tingkat Pengembalian Modal Internal Ekonomi

Economic Internal Rate of Return

FAO Organisasi Pangan Dunia Food and Agriculture Organization of the United Nations.

FS, F/S Studi Kelayakan Feasibility Study

FY Tahun Anggaran Fiscal Year

GDP Produk Domestik Bruto Gross Domestic Product

GIS Sistem Informasi Geografi Geographical Information System

GOI Pemerintah Indonesia Government of Indonesia

GPS Penentuan Posisi Global Global Positioning System

GRDP Produk Domestik regional Bruto Gross Regional Domestic Product

IBRD Bank Dunia International Bank for Reconstruction and Development (World Bank)

IEE Initial Environmental Examination

GLOSSARY

G-ii

JBIC Japan Bank for International Cooperation(Former OECF)

JICA Japan International Cooperation Agency

LAN Jaringan Komputer Lokal Local Area Network (Computer)

MCM Juta Meter Kubik Million Cubic Meters

MP, M/P Rencana Induk Master Plan

MSL Tinggi Muka Air Laut Rata-rata Mean Sea Level

NGO Lembaga Swadaya Masyarakat Non-Governmental Organization

NPV Nilai Sekarang Neto Net Present Value

O&M Operasi dan Pemeliharaan Operations and Maintenance

OECF Badan Penyandang Dana Jepang Overseas Economic Cooperation Fund (Japan), Now reorganized JBIC

OJT Latihan di Lapangan On-the-Job Training

PCM Pertemuan Konsultasi Masyarakat Public Consultation Meeting

R Sungai River

S/W Scope of Works

TIU Unit Pelaksana Teknis Dinas Technical Implementation Unit

UNESCO Badan Pendidikan, Ilmu Pengetahuan dan Kebudayaan, P.B.B

United Nations Educational, Scientific, and Cultural Organization

USAID Badan Penyandang Dana Amerika Serikat

United States Agency for International Development

VAT Value Added Tax

WATSAL Wanita dalam Pembangunan Water Sector Adjustment Loan

WID Pengembangan Sumber Daya Air Women in Development

WUA Federasi Petani Pemakai Air Water Users Association

GLOSSARY

G-iii

(INDONESIAN ABBREVIATION)

AMDAL Analisis mengenai Dampak Lingkungan Environmental Impact Analysis

ANDAL Analisis Dampak Lingkingan Environment Impact Statement

APBD Anggaran Pendapatan dan Belanja Daerah

Regional Income and Expenditure

APBN Anggaran Pendapatan dan Belanja Nasional

National Income and Expenditure

Ass. Asisten Assistant

BAKORNAS PBP

Badan Koordinasi Nasional Penanggulangan Bencana dan Penanganan Pengungsian

National Coordination Board of Disaster and Evacuation

BAPEDAL Badan Pengendali Dampak Lingkungan Environmental Impact Management Board

BAPEDALDA Badan Pengendali Dampak Lingkungan Daerah

Regional Environmental Impact Management Agency

Bappeda Badan Perencanaan Pembangunan Daerah

Provincial Development Planning Board

Bappenas Badan Perencanaan Pembangunan National

National Development Planning Board

Binlak Pembinaan & Pelaksanaan Construction Management

BMG Badan Meteorologi dan Geofisika Meteorological and Geophysical Institute

BPS Badan Pusat Statistik National Statistics Office

Bupati Kepala Daerah Tingkat II/Kabupaten Head of District (Regency)

CD, Cabdin Cabang Dinas Branch of Dinas

DATI I Daerah Tingkat I Regional Level I (Province)

DATI II Daerah Tingkat II Regional Level II (District)

DI Daerah Irigasi Irrigation Schemes

DinasPU, DPU Dinas Pekerjaan Umum Public Works Services

DIP Daftar Isian Proyek List of Project Budget

DPR Dewan Perwakilan Rakyat National Parliament

DPRD Dewan Perwakilan Rakyat Daerah Regional Parliament

DPU Departemen Pekerjaan Umum Ministry of Public Works

GLOSSARY

G-iv

DPUP Dinas Pekerjaan Umum Propinsi Provincial Public Works Services

DTP Dinas Tanaman Pangan Office of Food Crops

Kanwil Kantor Wilayah Regional Office (of a Department)

Kaur Kepala Urusan Head of Sub Section

KDH Kepala Daerah Head of Regional Government

KDPP Kepala Daerah Pengamatan Pengairan Head of Water Resources Sub District

Kepmen Keputusan Menteri Minister’s Decree

Keppres Keputusan Presiden Presidential Decree

KIMPRASWIL Departemen Permukiman dan Prasarana Wilayah

Ministry of Settlement and Regional Infrastructure (MSRI)

KSDP Kepala Sub Dinas Pengairan Head of Provincial Water Resources Service

KTL Kegiatan Tindak Lanjut Follow-up Activity

KUD Koperasi Unit Desa Village Cooperative Unit

LBB Limboto-Bolango-Bone Limboto-Bolango-Bone

LSM Lembaga Swadaya Masyarakat Non-Governmental Organization

MONEV Monitoring & Evaluasi Monitoring & Evaluation

O&P Operasi dan Pemeliharaan Operations and Maintenance

P3A Perkumpulan Petani Pemakai Air Water Users’ Association (WUA)

P3SU Proyek Pembinaan Pengairan Sulawesi Utara

North Sulawesi Water Resources Institutional Development Project

PDAM Perusahaan Daerah Air Minum Regional Water Company

PDSA Pengumpulan Data Sumber Air Water Resources Data Collection

PEMDA Pemerintah Daerah Regional Government

PERDA Peraturan Daerah Regional Regulation

Pimpro Pemimpin Proyek Project Manager

Pinbagpro Pemimpin Bagian Proyek Sub Project Manager

PJP Program Jangka Panjang Long Term National Dev. Program

PLN Perusahaan Listrik Negara State Electricity Company

PPTPA Panitia Pelaksanaan Tata Pengaturan Air Basin Water Management Committee

GLOSSARY

G-v

PSDA Pengamanan Sumber Daya Air Water Resources Conservation

PTPA Panitia Tata Pengaturan Air Provincial Water Resources Committee

PU Pekerjaan Umum Public Works

Puslitbang Pusat Penelitian dan Pengembangan Pengairan PU

Institute of Hydraulic Engineering Center (Bandung)

PWS Pengembangan Wilayah Sungai River Basin Development

RKL Rencana Pengelolaan Lingkungan Environmental Management Plan

RPL Rencana Pemantauan Lingkungan Environmental Monitoring Plan

SATKORLAK PBP

Satuan Koordinasi Pelaksanaan Penanggulangan Bencana dan Penanganan Pengungsian

Implementation Coordination Unit of Disaster Mitigation and Evacuation

SATLAK PBP Satuan Pelaksanaan Penanggulangan Bencana dan Penanganan Pengungsian

Implementation Unit of Disaster Mitigation and Evacuation

SDA Sumber Daya Air Water Resources

Sulut Sulawesi Utara North Sulawesi

Tkt. I Tingkat I Level I Administration (Province)

Tkt. II Tingkat II Level II Administration (Region)

UNSRAT Universitas Sam Ratulangi Sam Ratulangi University

UPTD Unit Pelaksana Teknis Dinas Technical Implementation Unit

GLOSSARY

G-vi

(SOME INDONESIAN WORDS)

Desa Village (rural area), The Lowest Administrative Unit, Headed by Kepala Desa or Kades who is elected by the residents

Kabupaten, Kab. Administrative District Headed by Bupati (regency)

Kecamatan, Kec. Administrative Sub District within the Kabupaten

Kelurahan Village (urban area), The Lowest Administrative Unit, Headed by Lurah who is Appointed

Kota Municipality, Administrative District Headed by the Walikotamadya

Kotamadya Municipality, Administrative District Headed by the Walikotamadya

Propinsi Province

Ribu thousand = 1,000

Juta million = 1,000,000

Milyar billion =1,000,000,000

Trilyun trillion = 1,000,000,000,000

Tomini Bay

Lake Limboto

Rintenga RiverRintenga RiverRintenga River

AlopohuAlopohu River RiverAlopohu River

MarisaMarisa River RiverMarisa River

MeluopoMeluopo River RiverMeluopo River BiyongaBiyonga

River RiverBiyonga River

BolangoBolangoRiverRiverBolangoRiver

TamalateTamalate River RiverTamalate River

Bone RiverBone RiverBone River

Tapodu RiverTapodu RiverTapodu River

Alo RiverAlo RiverAlo River

Pohu RiverPohu RiverPohu River

Reksonegoro RiverReksonegoro RiverReksonegoro River

N

NAME OF RIVER

Bridge

① Tenda Bridge ⑨ Biawu-2 Bridge

② Siendeng-1 Bridge ⑩ Tenilo Bridge

③ Siendeng-2 Bridge ⑪ Potanga Bridge

④ Donggala Bridge ⑫ Tapodu Bridge

⑤ Siendeng Bridge ⑬ Tilote Bridge

⑥ (Footpath Bridge) ⑭ Road Bridge ⑦ Biawu-1 Bridge ⑮ (Footpath Bridge) ⑧ (Footpath Bridge) ⑯ Talumolo Bridge

Bolango R.Tapodu R. Bolango R. (Stretch-III) Left Bolango R. (Stretch-IIL)

Siendeng R. or Right Bolango R.

(Stretch-IIR )Lower Bolango R.

Bolango R.(Stretch-I) Bone R.

Low

er Bone R

.

Sea

⑯①

②

⑤⑥⑦⑧⑨

③

④⑩⑪⑬ ⑮ ⑭ ⑫


A1-1

A1. TOPOGRAPHY AND GEOLOGY A1.1 Topography (1) North Sulawesi Sulawesi Island is the third largest in area of the Larger Sunda Islands, following Kalimantan, Sumatra islands, being entirely occupied by mountainous topography. The island consists of four narrow branches or arms, separated by deep gulfs and uniting in a central trunk, stretching in its typical outline of K.

The Sulawesi Island is surrounded by deep basis and troughs namely, the Sulawesi basin in the north, the Makassar trough in the west, Maluku and North Banda basins in the east, and South Banda (Flores) basin in the south. The Study Area of the Limboto–Bolango–Bone basin is located in the central part of north arm (the Minahassa Peninsula) of Sulawesi Island. The Minahassa Peninsula stretches E-W direction in general, with its eastern end in NE-SW direction. The peninsula narrows down to 30km around Dondo Bay in the western end, and changes the trend to N-S direction toward Central Sulawesi. Eastern part of the Minahassa Peninsula, trending NE–SW in direction, has active volcanoes extending onto Mindanao of the Philippine archipelago via Sangihe Islands. The central and western part of the Minahassa Peninsula has an E-W direction. The width of this section changes from 35km in the central to more than 100km in the western part. The whole of the Minahassa Peninsula is mountainous in general, except for sporadic coastal lands and some part of the area where a longitudinal depression stretches between the mountainous ranges of the north and those of the south coast. This longitudinal depression is observed also in the Study Area. (2) Study Area The Study Area is located in the central part of the Minahassa Peninsula covering total area of 2,700 km2 consisting of three major basins such as Lake Limboto, Bolango River and Bone River basins. Topography of the Study Area is dominantly oriented in the E-W direction, bounded by the east-west oriented mountain ranges on the north and the south, and flat lowland plain in-between


A1-2

The basins of Lake Limboto and the Bolango River are located in the western half of the Study Area and the Bone River basin in the eastern half of the area. All rivers flow dawn to the central lowland plain from mountainous area and finally empty into the Tomini Bay at southern most of the Gorontalo City. The Biyonga, Alo, Molamahu, Pohu, Rintenga rivers are the main rivers flowing into Lake Limboto. The Bolango River, joining the outlet channel of Lake Limboto in the lower reaches, flows into the Bone River. The Bone River drains the eastern half of the LBB basin into the sea together with western half of the basin consisting of the Bolango River and Lake Limboto basins. These rivers are dissecting mountains and transporting sediments to lowland plains. It is assumed from the existence of unconsolidated lake deposits found in these basins that there used to be a large scale impounding reservoirs covering these basins. The Limboto Lake appears to be its remnant. The topography of the study area is shown in Figure A1.1.1. A1.2 Geology (1) North Sulawesi Sulawesi appears to be formed by the collisions of two main crustal plates on the surface of the earth. The Australian plate is thrust westwards by sub-crustal magma currents, and it collides with the rigid Asian plate. The collisions were accompanied by considerable crust faulting and rotation of the fragments of the main plates. The Australian plate is being subducted beneath the Asian plate and it causes periodic rifting and separation of the fragments of the plate. The North Sulawesi together with the South Sulawesi is split along the line of Makassar Strait from Asian plate of eastern Kalimantan due to the said tectonic process during the middle of Tertiary. According to the report prepared by Hamilton(1998), the North Sulawesi belongs to the Cretaceous subduction system. The oldest pre-Tertiary basement rocks of a complex of metamorphic and ultra basics are exposed in south western end of the North Sulawesi. Subsequently early-to-mid Tertiary volcanic rocks inter-bedded with sedimentary rocks are distributed covering the said basement rocks. Granite intrusions occurred in Middle and late Tertiary and they are widespread in the North Sulawesi closely associating mineralization.


A1-3

Sandstones, volcanic conglomerates and thin beds of lime stones were formed in late Tertiary. They are mostly observed in the northern part of the North Sulawesi. Relatively less consolidated and gently dipping sedimentary strata called “Celebes Mollasse”, which consists of conglomerates, quartz sandstones, shale, marls, coral lime stones are distributed mainly over granites and granitized rocks. Volcanic rocks of andestic and/or dacitic composition were intruded through the above strata in early Quaternary and they formed the highest mountains in the region. Recent deposits of sands, gravels and coral reefs are distributed covering the said all strata. Stratigraphy of the area is described in Table A1.2.1. (2) Study Area Geology of the study area consists mainly of igneous, volcanic and sedimentary rocks of middle Tertiary to early Quaternary periods. Volcanic and sedimentary rocks formed prior to igneous intrusion are slightly to highly metamorphosed, and the original state of highly metamorphosed rocks are somehow undistinguishable. Some sedimentary rocks are granitized and metamorphosed. The strata of pre-Mid-Tertiary appear to form the basement rocks in study area. They consist of igneous rocks of granites and grano-diorites as well as metamorphosed rocks. Sedimentary rocks of late Tertiary appear not to exist in the area. However, existence of crystallized state of lime stones indicates distribution of Tertiary sedimentary rocks prior to the latest volcanic event of early Quaternary. Sedimentary rocks of late Quaternary are distributed in the Study Area. They are composed of clay stone, sandstone, conglomerate and limestone. Latest volcanic activities of early Quaternary formed the frame of the present topography in the study area. Andestic and dacitic lavas as well as agglomerates spread in high peaks of the area. Non-welded tuffs are also observed along the right bank of the Bone River. Unconsolidated deposits of gravels and sands are widely distributed in the lowland of the basin. Talus and terrace deposits are also distributed in scarps of hilly and as well as mountainous areas covering the older formations. Geological map and schematic profile of the study area are shown in Figures A1.2.1 and A1.2.2, respectively.


A1-4

A1.3 Geotechnical Conditions Geological and geotechnical data obtained during the study period are reviewed and confirmed by the geological reconnaissance. Several dam-site data presented in the previous study reports were included among them. The dams proposed by the previous studies are located in the Bolango, Biyonga, Marisa, Alo and Molamahu rivers. Core drillings were also carried out by the Study Team to obtain geotechnical information for possible dam and structure sites and lowland plain. The geotechnical conditions of the possible structure sites are described below in brief based on the previous study results and the core drilling data obtained by the Study Team. (1) Dam Sites Two dam sites, Toheti-Dehua dam along the Bolango River and Kayu-Merah dam along the Biyonga River have been selected for further flood control study, according to results of previous study by CIDA. These dam sites were selected for geological investigations during the Master Plan study period. Five (5) boreholes were drilled in each proposed dam site. Three (3) boreholes are allocated in dam axis and one (1) borehole each in the upstream and downstream sections as shown in Figure A1.3.1. Toheti-Dehua Dam in Bolango River The dam site is located on the Bolango River just downstream of the confluence with the Monglilo River. The river section of the dam site is relatively wide of nearly 300 m and the slopes of both abutments are moderately steep. Geological map and sections are shown in Figures A1.3.2 and A1.3.3 based on the results of drillings. The basement rock is confirmed to be igneous rocks of granites, grano-diorites and hornfels and/or quartzite. The basement rock is covered with alluvial deposits of maximum thickness of around 35 m according to the drilling results. Top portion of the basement rock is moderately weathered and judged to be CL to CM in rock grade, and moderately large permeability of 5 x 10-4 cm/sec is recorded as the results of core drilling and permeability test performed for this study. Fresh state of the basement rock is sound enough of CM to CH in rock grade and permeability is quite low of 1.0 x 10-5 cm/sec according to the drilling results.


A1-5

Kayu Merah Dam in Biyonga River The dam site is located on the Biyonga River, at around 2 km upstream from the topographical boundary between the flood plain and mountainous area. Geological map and sections are shown in Figures A1.3.4 and A1.3.5 based on the results of drillings. The slopes of abutments are moderately gently in both sides of the river, and river valley is relatively wide. The basement rock confirmed to be igneous rocks of Hornfels and dacite in the area. Basement rock is hard and compact and classified to be CM to CH in rock grade. Permeability of the foundation rock is low of 1 x 10-4 to 3 x 10-5 cm/sec as the result of permeability test. The basement rock is sound enough for dam foundation. Other Dam Sites Discussed in Previous Studies Marisa River: The dam site is located on the Olitabu River 1 km upstream from the junction between Olitabu and Buliyaa rivers, which both rivers are tributaries of the Marisa River. The dam site is situated near the village of Marisa. The slopes of both abutments are moderately gentle and the river terrace is relatively wide. The bedrocks appear to be composed of sedimentary rocks of mudstone alternating with sandstones, however, igneous and volcanic rocks underlying the sedimentary rocks are widely distributed nearby. The sedimentary rocks are relatively soft and highly weathered in general. Unconsolidated deposits, such as riverbed, terrace and talus deposits, are distributed covering the said rocks. The strength of the bedrocks and thickness of unconsolidated deposits shall be examined when the dam is planned. Buhiyaa River: The dam site is located on the Buhiyaa River, around 500 m upstream from the topographic boundary between the lowland plain and hilly terrains. The slopes of both abutments are steep and they consist of coral lime stones. The lime stones of the bed rocks are massive and slightly weathered in dam site. No relatively large-scale cavities were observed in exposed rocks. The bedrock of lime stones appears to have enough strength for dam foundation, however seepage from the reservoir shall be assumed due to cavities which may exist in lime stones in general. Molamahu River: The dam site is located on a tributary of the Molamahu River, where the topographic boundary between flood plains and hilly and mountainous areas. The


A1-6

slopes of the abutments are steep and/or relatively steep in general, however terrace are formed along the river stream in height of around 10 m at places. The bedrock consists of coral lime stones underlying by sedimentary rocks, of which assumed to be sandstones and mudstones. The bedrocks are covered with terrace and present river deposits. The bedrock is relatively soft however it appears to have enough strength for 20 m high concrete structure proposed by CIDA. Coral lime stones of the bedrock have cavities observed in rock exposes. Foundation treatment will be needed as seepage through cavities is envisaged. (2) Lowland Plain Eight (8) boreholes were also drilled to confirm geotechnical conditions of lowland plain during the Master Plan study period. Locations of points A through H are indicated in the Figure A1.3.1. Results of drilling executed in the lowland plain are presented below by the points. Point A: Point A is located in the lowland plain along Biyonga River at the north of Lake Limboto. Topographic boundary between lowland plain and hilly terrain is situated near the point A. Drilling hole was selected to place near the road. As a result of the drilling, recent deposits of around 4 m in thickness was confirmed to reach the foundation rock. The foundation rock of soft sandstone was confirmed in point A. N values of more than 50 were recorded below the depth of 4 m. Sound foundation can be obtained at depth of 4 m below ground surface. Point B: Point B is located in northeast of Lake Limboto in between Bolango and Biyonga rivers, near topographical boundary between lowland plain and hilly terrain. Recent deposits of sandy gravels in thickness of a few meters were confirmed over base rock of volcanic. N-value of more than 30 was recorded in all section as a result of standard penetration tests, and it secures sound foundation for small structures. Point C: Point C is located near Pilohayanga weir on Bolango River in northeast of Lake Limboto. Only river deposits of sandy gravels are confirmed in whole length of the borehole, therefore bedrock lays more than 15 m below the ground surface. N value of less than ten (10) is recorded in shallower portion of 3 m in thickness below the ground surface. N-value of ten (10) to thirty (30) are recorded at depth of below 3 m from ground surface. Attention shall be paid to foundation of structures in such poor geotechnical condition.


A1-7

Point D: Point D is located near northern shore of Lake Limboto. Clay and loose unconsolidated fine to medium sand are distributed in shallower portion of the area, however sand is confirmed at depth of more than 6 m below ground surface. N values of more than 30 are recorded at depth of more than 10 m below ground surface. Relatively poor geotechnical condition is confirmed up to 5 m in depth. Point E: Point E is located near northeast shore of Lake Limboto. No bedrock is confirmed up to 15 m in depth. Loose unconsolidated deposits of clay and fine to medium size of sand are confirmed in shallower and deeper portion of the borehole. Sandy deposits showing N value of more than 30 are distributed at depth between 7 to 10 m below ground surface. Relatively poor geotechnical condition is confirmed up to 5 m in depth. Point F: Point F is located along Bolango River in the east of Lake Limboto. Irrigation canal exists near the drilling hole of this point. River deposits and/or deposits of flood plain are confirmed through drilling works. Bed rock of volcanic is also confirmed at depth more than 6 m below ground surface. N values of more than 50 are recorded in the bedrock layer. Relatively poor geotechnical condition is confirmed up to 5 m in depth, however sound foundation can be obtained in bedrock layer at depth of 6 m below ground surface. Point G: Point G is located at outlet of Lake Limboto along southeast of the lake shoreline. Loose and moderately consolidated deposits of various size of sand are distributed there. Sandy gravel layer is encountered with intercalation of medium to coarse sand deposits throughout the drilling hole. Attention shall be paid to foundation of structures in such poor geotechnical condition. Point H: Point H is located near center of Gorontalo city in the east of Lake Limboto. The area near point H is becoming residential area of Gorontalo city, though the point H is situated in the paddy field. Top soil of the paddy field is relatively loose and shows 14 in N value, however N values of more than 50 was recorded throughout the drilling hole except top soil of 6 m in thickness. Sound foundation for small structures can be obtained at depth of 3 m below the ground surface.


A1-8

(3) Structure Sites During the Feasibility Study period, core drillings were conducted by the Study Team at major structure sites to obtain geotechnical information on subsurface conditions of these structures. In addition, boring was conducted at the estuary of the Bone River to confirm the riverbed conditions which forms abrupt drop facing to the sea. Tapodu Gate: Tapodu gate is located at around 1km downstream of the outlet of Lake Limboto. No base rock was confirmed according to the drilling works. However, recent deposits of sandy gravel are distributed in the river section. Sandy gravel layers of more than 30 in N value appear to have sufficient strength for foundation of the structures. Tamalate Weir: Tamalate weir is planned to build in the inlet of Tamalate Floodway and recent deposits of sand and gravel are distributed around the area. No bedrock was confirmed through drilling works. However, outcrops of tuff breccia are observed around 200m west of the weir site. Base rock of the site appears to be the tuff breccia according to the site reconnaissance of the area. Estuary of Bone River: Borings were conducted at five (5) boreholes in the stretch from river mouth to confluence of the Bone and Bolango rivers. Out of the five, one borehole was extended to 15 m in depth. As a result, no bedrocks were confirmed at any boreholes. The riverbed of the Bone estuary is formed by thick sand and gravel sediments. The abrupt drop of riverbed at the sea front seems to be formed by river sediment and deep seabed like sediment deposition seen in dam reservoirs.

Recent Sand , Gravels , coral reefs

Conglomerates , Quartz , sand-Early stones , Shale , Marls , CoralQuaternary Sedimentary rocks limestones ( Celebes Molasse

gently dipped)

Early Andestic and dacitic lavas , Quaternary Volcanic rocks Tuffs in same composition

Late Quartz sandstone , SilicifiedTertiary Sedimentary rocks sandstone , Volcanic conglomerates

Limestone ( relatively thin )

Mid-Late Igneous rocks Granites , Granodiorites ,Tertiary Gabbros

Middle Volcanic rocks Lavas , Breccias , AgglomeratesTertiary interbedded with sandstones ,

Siltstone , Shales and Limestones

Early Pillow lava , Tuff brecciasTertiary Volcanic rocks Agglomerates interbedded

with Sandstone , ( Red ) Shale ,Limestone , greywacke ,Tuff , Claystone, etc.

Cretaceous Metamorphic complexes Greenshist , Gneiss ,Quartzite , Phyllites ,Biotite-quartz schist, etc.

Table A1.2.1 GEOLOGICAL STRATIGRAPHY OF NORTH SULAWESI

CENOZOIC

MESOZOIC

A1-9

Source: JOG Map - US Army, 1967

05

1015

2025

30 Km

SCALE

LIMBOTO

LAKE

LIMBOTO

ISIMU

GORONTALO

BOLANGO

BONE

RINTENGA

BIYONGA

POHU RIVER

MOLAMAHU

ALO RIVER

RIVER

RIVER

RIVER

RIVER

RIVER

Legend

Elevation (m,MSL)

0 ~ 100

100 ~ 500

500 ~ 700

700 ~ 1000

1000 ~ 1500

The Study on Flood Controland Water Management

in Limboto-Bolango-Bone Basinin the Republic of Indonesia

Japan International Cooperation Agency

Figure A1.1.1

TOPOGRAPHY OF STUDY AREA

A1-10

DANAU

LIMBOTO

GORONTALO

LIMBOTO

ISIMU

BONE

BOLANGO

BIYONGA

ALO RIVER

RINTENGAPOHU

RIVER

MOLAMAHU

RIVER

RIVER

RIVER

RIVER

RIVER

Sand & Garvel

Reef Limestone

Andesit, Decite, Tuff

Sandstone, Claystone

Recent Deposits

Volcanics

Coral LImestone

Sandstone, Conglomerate

Granite Grano-Diorite

Hornfels

Sedimentaty Rocks

Quarternary

Tertiary

(Early Quarternaly)

Metamorphosed Rocks

Ignous Rocks

(Mid-Late Tertiary)

05

1015

2025

30 Km

SCALE




Figure A1.2.1

GEOLOGICAL MAP OF STUDY AREA

A1-11

PIN

OG

UG

OR

ON

TALO

LIM

BO

TO L

AK

EIS

IMU

SU

LAW

ES

I SE

ALI

MB

OTO

LA

KE

TOM

INI B

AYSa

nd &

Gra

vel

Ree

f Lim

esto

ne

And

esite

, Dac

ite, T

uff

Sand

ston

e, C

layd

tone

Cor

al L

imes

tone

Sand

ston

e, C

ongl

omer

ate

Sand

ston

e

Hor

nfel

s

Gra

nite

. Gra

no-d

iorit

e

TERT

IARY

QU

ART

ENA

RY

Lege

nd

N -

S

W -

E




Figure A1.2.2SCHEMATIC GEOLOGICAL PROFILEOF STUDY AREA

A1-12

Shallow core drilling : 8 holes ( A through H)

(for important alternative facilities)

Biyonga River

Bolango River

Core drilling: 5 hole

(for proposed dam)

Core drilling: 5 hole

(for proposed dam)

Notes:

1) Core drilling at 18 holes in total.

2) Exact locations of the boreholes are indicated at site by the Engineer

: Proposed dam site

30m - deep hole

20m - deep hole

15m - deep hole

Sea

Bone R.

Bolango R.

Biyonga R.

Alo R.

Pohu R.

L.LimbotoA

BC

DE F

GH




Figure A1.3.1LOCATION OF DRILLING HOLES(1/2 : M/P STAGE)

A1-13

Date post:	08-Aug-2019
Category:	Documents
Upload:	ngocong
View:	220 times
Download:	0 times

EXISTING CONDITIONS - JICAopen_jicareport.jica.go.jp/pdf/11709755_01.pdf · japan international...

Documents