Public Disclosure Authorized Final Report – phase 2 Public Disclosure Authorized Public Disclosure Authorized Public Disclosure Authorized December 2014 FHM – Technical review and support Jakarta Flood Management System Including Sunter, Cakung, Marunda and upper Cideng Ciliwung diversions and Cisadane Technical review and support Jakarta Flood Management System Final Report - phase 2 © Deltares, 2014 December 2014, Final Report - Phase 2 Contents 1 Introduction 1 1.1 Background 1 1.2 Introduction to the project 2 1.3 Polder systems 2 1.4 Project Tasks 4 1.5 Report outline 5 2 Kamal / Tanjungan polder 7 2.1 Description of the area 7 2.2 Pump scheme alternatives 8 2.2.1 A1 – Kamal and Tanjungan as separate systems, no additional storage 9 2.2.2 A2 – Combined Kamal and Tanjungan system, storage reservoir 45 ha 12 2.2.3 A3 – Kamal-Tanjungan with 90 ha storage 14 2.3 Verification with the hydraulic model and JEDI Synchronization 15 2.3.1 Introduction 15 2.3.2 Results 16 2.3.3 Impact of creation of western lake NCICD 18 2.4 Synchronization with other hydraulic infrastructure 19 3 Lower Angke / Karang polder 20 3.1 Description of the area 20 3.2 Pump scheme alternatives 21 3.2.1 B1 – Lower Angke/Karang, no additional storage 22 3.2.2 B2A – Lower Angke/Karang, new reservoir at Lower Angke 23 3.2.3 B2B – Lower Angke/Karang, 30 ha waduk and 12 ha emergency storage 25 3.2.4 B3 – as B2B, but with all possible green area as emergency storage 27 3.2.5 B4 –Splitting the polder in two parts, no additional storage 29 3.2.6 B5 –Splitting the polder area in two parts, additional storage 33 3.2.7 Other possible options 37 3.3 Verification with the hydraulic model and JEDI Synchronization 37 3.3.1 Introduction 37 3.3.2 Results 38 3.3.3 Impact of creation of western lake NCICD 40 3.4 Synchronization with other hydraulic infrastructure 41 4 Marina/Sentiong polder 42 4.1 Description of the area 42 4.2 Pump scheme alternatives 44 4.2.1 C1 – Marina/Sentiong, no additional storage 45 4.2.2 C2 – Marina/Sentiong and Sunter Utara, no additional storage 47 4.2.3 C3 – Marina/Sentiong and Sunter Utara extra open space 49 4.2.4 C4 – Marina/Sentiong, including Sunter Utara and a Marina retention 51 3 4.2.5 C5 – Marina/Sentiong, as C2 plus continuous 70 m /s Ciliwung Lama 53 4.2.6 C6 – Marina/Sentiong, as C5, but inflow Ciliwung Lama after local rainfall 55 4.3 Verification with the hydraulic model and JEDI Synchronization 57 4.3.1 Introduction 57 4.3.2 Results 59 Technical review and support Jakarta Flood Management System i December 2014, Final Report - Phase 2 4.3.3 Impact of creation of western lake NCICD 60 4.4 Synchronization with other hydraulic infrastructure 60 5 Sunter polder 63 5.1 Description of the area 63 5.1.1 Introduction 63 5.2 Pump scheme alternatives 64 5.2.1 Sunter drain outlet 64 5.2.2 Sunter drain design 64 5.3 Verification with the hydraulic model and JEDI synchronisation 65 5.3.1 Introduction and results 65 5.3.2 NCICD developments 65 5.3.3 Catchment boundaries and connections 66 6 Cakung polder 67 6.1 Description of the area 67 6.2 Pump scheme alternatives 69 6.2.1 Cakung drain outlet 69 6.2.2 Cakung drain design 69 6.3 Verification with the hydraulic model and JEDI synchronisation 70 6.3.1 Introduction and results 70 6.3.2 Cakung Lama system 71 6.3.3 Secondary systems 71 6.4 Alternatives for further development under future scenarios, including NCICD 72 3 6.4.1 No plan integration: increasing pump-capacity to 250m /s 72 6.4.2 Using 445ha retention pond to extend retention volume 72 6.4.3 Integrate pump scheme in NCICD phase 3 72 7 Marunda polder 74 7.1 Description of the area 74 7.2 Pump scheme alternatives 75 8 Upper Cideng - Setiabudi 76 8.1 Introduction 76 8.2 Modelling 79 8.3 Conclusions 81 9 Review of the proposed Ciliwung-BKT and Cisadane diversions 82 9.1 Diverting flow from the Ciliwung 82 9.1.1 Ciliwung – BKT diversion 83 9.1.2 New flood strategy for the Ciliwung – BKB system 84 9.1.3 Katu Lampa – Cisadane diversion 84 9.2 Ciliwung-BKT diversion 84 9.2.1 Introduction 84 9.2.2 Improvements required at the BKT and Cipinang 85 9.2.3 Diversion capacities 87 9.2.4 Effect of diversions on Ciliwung and Banjir Kanal Timur water levels 88 9.2.5 Towards “equal distribution” 92 9.2.6 Prefer ability of alternative 93 9.3 Alternatif Diversion Channel (Sudetan) Ciliwung - BKT 94 ii Technical review and support Jakarta Flood Management System December 2014, Final Report - Phase 2 9.3.1 Ciliwung (Jembatan Kampung Melayu) – Banjir Kanal Timur (Jl. Basuki Rachmad) 94 9.3.2 Opsi Pembuatan Sudetan Ciliwung-Banjir Kanal Timur 97 9.3.3 Opsi Alternatif Outlet Diversion 99 9.3.4 Pengaruh sudetan alternatif 1 pada muka air Ciliwung dan Banjir Kanal Timur 103 9.4 Preliminary review Ciliwung – Cisadane diversion 107 9.4.1 Diversion Katu Lampa-BKT, Nikken 1997 107 9.4.2 Diversion Katu Lampa-Cisadane, Deltares 2014 110 10 Extension of the Jakarta FHM modelling framework 116 10.1 History of Jakarta FHM modelling framework 2007 – 2013 116 10.2 The Jakarta SOBEK modelling system 118 10.3 The Jakarta FHM- modelling framework 118 10.3.1 Overview 118 10.3.2 The rainfall-runoff model 119 10.3.3 The 1D-2D Flow schematization 120 10.4 Extension with Cisadane and Bekasi river systems 121 10.4.1 First overview of the Cisadane and surrounding catchment 121 10.5.1 Model setup 123 10.5.2 Model calibration 123 10.5.3 First overview of the Bekasi and surrounding catchment 125 10.5.4 Model setup 126 10.5.5 Model calibration 126 11 Updating JFM and FMIS databases 128 11.1 Processing of Digital Elevation Map 128 11.2 Description of Lidar based DEM 128 11.2.1 Origin of retrieve data 128 11.2.2 Projection and datum 128 11.2.3 Review on filtering 129 11.3 Comparison of Lidar with 1D geometry 131 11.4 Lidar derivatives 131 11.4.1 Streamlines for sub-catchment delineation 131 11.4.2 Updating the FHM framework databases 132 Appendix A – Methodology 134 Appendix B – Sobek and the Jakarta FHM framework 149 Technical review and support Jakarta Flood Management System iii December 2014, Final Report - Phase 2 1 Introduction 1.1 Background Greater Jakarta is the political and economic centre of Indonesia. With an estimated population of over 28 million, it accounts for a quarter of the nation’s non-oil GDP. The Province of Jakarta (Daerah Khusus Ibukota or DKI) lies in the delta of the Ciliwung River and has a population of about 10 million. About 40% of the city is below sea level and large areas are flooded during the rainy season each year. Especially severe floods occurred in February 2002, February 2007, and again in January 2013 and 2014, when more than 25% of Jakarta was inundated, flooding up to a depth of 5 meters in places, causing deaths and displacing of more than 100,000 inhabitants. The economic costs were significantly higher considering loss of life, health costs, and disruption to trade and industry. The severity of floods in the capital has become a national issue given the huge financial losses and the impacts on communities in the greater Jakarta area. For this reason, the Ministry of Public Works and the provincial government of DKI Jakarta are jointly embarking on an extensive flood management initiatives. DKI and the Ministry of Public Works has designed and prepared a program to normalize and improve the existing canal system by returning it to original design through Central Government and DKI Jakarta own sources as well as Bank’s financing through Jakarta Urgent Flood Mitigation Project/Jakarta Emergency Dredging Initiatives Project (JUFMP/JEDI Project). The dredging initiatives will transcend beyond structural works to ensure that there are proper additional measures to build capacity through programs, studies, and technical assistance in order to address the problems comprehensively, especially in terms of sustainability for ensuring long-lasting flood management systems known as non-structural measures. The sustainable effort of flood mitigation in Jakarta require substantial financing for investment, rehabilitation, operation and maintenance (O&M), and non-structural measures including capacity building, programing, improvement of technology and institutional arrangement. Especially on construction and O&M, sufficient financing strategy and availability will be the key for flood mitigation effort in Jakarta. The ongoing subsidence of Jakarta is causing problems for the water system of Jakarta. The plans for sea defence developed in JCDS (Jakarta Coastal Defence Study) are now being worked out in the NCICD (National Capital Integrated Coastal Development) project. However, the sea defence is not the only problem related to subsidence. The subsidence also poses problems for the drainage system of large parts of northern Jakarta. The drainage is at present mostly by gravity, but this is getting more and more difficult due to the sinking of the land. Therefore large parts of Jakarta need to become polder systems like the existing Pluit polder. The water level will be controlled by pumps which pump the drainage water to the Java Sea.