lizarB Santa Catarina State PREPARATORY SURVEY FOR THE PROJECT ON DISASTER PREVENTION AND MITIGATION MEASURES FOR THE ITAJAI RIVER BASIN FINAL REPORT VOLUME II :MAIN REPORT NOVEMBER 2011 JAPAN INTERNATIONAL COOPERATION AGENCY NIPPON KOEI CO., LTD GED JR(先) 11-179 lizarB Santa Catarina State PREPARATORY SURVEY FOR THE PROJECT ON DISASTER PREVENTION AND MITIGATION MEASURES FOR THE ITAJAI RIVER BASIN FINAL REPORT VOLUME II :MAIN REPORT NOVEMBER 2011 JAPAN INTERNATIONAL COOPERATION AGENCY NIPPON KOEI CO., LTD GED JR 11-179 FINAL REPORT Composition of Reports VOLUME I EXECUTIVE SUMMARY VOLUME II MAIN REPORT Part II : Master Plan Study Part II : Feasibility Study VOLUME III SUPPORTING REPORT (A) Hydrology (B) Flood Mitigation Plan (C) Natural Condition and Landslide Management Plan (D) Flood Forecasting and Warning System (E) Water Storage in Paddy Fields (F) Environmental and Social Considerations (G) Structural Design and Cost Estimate (H) Economic Evaluation VOLUME IV DATA BOOK CD EXCHANGE RATE The exchange rate used in this Study is: Master Plan (2010/10) Brazilian Real (R$1.0 )=US Dollar (US$0.58 ) = Japanese Yen(Y47.87) Feasibility Study(2011/06) Brazilian Real (R$1.0 )=US Dollar (US$0.63 ) = Japanese Yen(Y50.71) Legend City Road River Dam Basin e r r i v e Location Map of Itajai River Basin Master Plan of Flood Management for Itajai River Basin ■ Characteristics of the flood disasters in the Itajai ■ Flood Prevension and Mitigation Measures for Safety Level of 50-year Flood Project Cost Project Components Location Amount Priority for F/S River basin (R$ 103) Urban areas are developed over flood plain and houses are close to the river. Water storage in rice field All the basin 22,000ha 33,000 ○ This might cause frequent inundation and restriction of flow capacity of the river. Heightening existing flood control dams Taio, Ituporanga 2 dams 33,000 ○ Basin storage (small dams) Upstream area of Rio do Sul 7 locations 211,000 Urban areas extending to mountainous area, where are used as mainly Flood Gates Itajai (Itajai Mirim River) 2 gates 94,000 ○ pastures. This might increase peak discharge such as flash floods and Floodway Itajai, Navegantes ( Itajai River) 10.9 km 593,000 sediment-related disasters. New flood control dam Brusque 1 dam 95,000 River improvement (widening, dyke) Taio 3.7 km 114,000 River improvement (dyke) Rio do Sul 8.2 km 268,000 River improvement (dyke) Timbo 10km1.0 km 22, 000 Composite section with APP Blumenau (Itajai River) 15.8 km 267,000 River improvement (widening) Blumenau (Garcia, Velha River) 7.0 km 196,000 Ring dyke Ilhota 8.0 km 70,000 Modification of operation of existing hydropower dams Rio dos Cedros 2 dams - ○ Strengthening existing FFWS All the basin - 4,000 ○ ■ Structural Measures Modification Discharge of operation of existing Flood control hydropower dams Pre-release Time Heightening of Oeste Dam Composite section with APP ■ Non-Structural Measures : (Heightening by 2.0 m) Blumenau L=15.8 km Floodway, Itajai/Navegantes Strengthening of Existing FFWS L=10.9 km Widening, Dyke Taio L=3.7 km Dyke Timbo L=1.0 km Pinhal dam Rio Bonito dam Widening Garcia, Velha L=7.0 km Benedito Novo Concept of Mater Stations Dyke and Central Station Rio do Sul Indaial L82L=8.2 km Salete Basin storage (small dams) Ibirama Apiuna Gurabiruba 7 locations Flood gates, Itajai N=2 Brusque Mirim Doce Agua Clera Botuvera Pouso Redondo Salseiro Vidal Ramos Department responsible for FFWS Rainfall and Water Level Gauging Station (Defesa Civil or SDS) (ANA, EPAGRI, INMET, CELESC, etc) Management of Rainfall and Water Level Gauging Station (30 stations for FFWS) Meteorological Agency (CIRAM) Observation and Prediction of Rainfal Heightening of Spillway of Sul Dam Flood Forecast (Heightening by 2.0 m) New Rainfall and River Water Level Gauge Saltinho Establishment of Database System Informing to CONDEC and Municipalities New CCTV New flood control dam, Brusque Ringgy dyke, Ilhota L=8.0km Floodway, Itaj ai/Naveg antes L=10.9 km Existing Rainfall and River Water Level Gauge DlDevelopmen tfFldFtiMdlto of Flood Forecasting Model CONDEC and Municipalities 1) Rainfall Prediction Model 2) Runoff Analysis Model Judgment and Execution of Warning and 3) Inundation Analysis Model Evacuation GRAC and Municipalities (DC) Defesa Civils of Municipalities Support of Evacuation Activity Establishmento of Hazard Map and Flood Protection Activity Evacuation Manual Institution of FFWS Master Plan of Landslide Management for Itajai River Basin ■ Result of the Risk Assessment ■ Components of Landslide Management Master Plan Project Cost Purpose Measures Unit：R$×103 Avoidance of (1) Non-structural measures human lives loss a) Formulation of Early warning system for Landslide/Flash flood. 4,000 b) Disaster education Reducing 13 High Risk landslide (2) Structural measures for landslide 19,000 economic losses 54 Medium Risk Structural measures from the priority sites which have high potential annual loss. landslide 35,000 Total 54,000 (3) Sediment yield mitigation by forestation. Forestation of bare collapsed land, prevention of river-bank erosion by river bank ー fores t will be p ro m ot ed. Pr ev enti on of sedim ent yi el d will be secur ed by v eget ati on at structural measures sites for landslide. (4) Flash flood/Flood mitigation by discharge regulation facilities ー Installation of discharge regulation facilities for rainfall runoff . (5) Capacity building for structural measure and support for private self –reliant effort a) Capacity building for structural measure project ー b) Support for private self –reliant effort of structural measures by subsidy. Risk (potential annual loss) Nos of sites ■Non-structural measures Low level（Less than 881 50,000R$/year) Early warning system for Landslide/ flash flood Medium level(50,000‐ 54 500,000R$/year Solar-powered automatic rain High level(over 500,000Rs/year) 14 GPRS /CELESC communication Total 949 Data accumulation by data logger EPAGRI/CIRAM Data Logger - Management of data from the whole SC State Struc tura l measures for lan ds lide - Setting/reviewing of rainfall index criteria for ■ attention and alert Legend Safety level: to ensure half functionality of Internet data uploading - On-time analysis of rainfall index including Road forecasting rainfall by WRF (Weather infrastructures and/or building/lands against heavy rain Research and Forecasting) model of 293 Federal paved roads, two lanes each way of 60 years return period, (heavy rain level in Nov 2008 Each Municipality Federal paved roads - Download data by each municipality Defesa Announcement Public relation of State paved roads, two lanes each way at Blumeau City Civil/CELESC of ttention/alert attention/ alert by to a concerned State paved road television/ radio/ - Announcement/public relation of organizations State unpaved roads gravel base attention and alert to residents/ travelers Web State unpaved roadsnatural by bulletin board, urgent Municipality paved roads communication network, church bell, Defesa Civil SC public relation vehicle Official issue of the attention/alert, preparation Municipality unpaved roads for emergency Boundary - Preparation for emergency Itajai Basin - Evacuation order to designated houses - Traffic regulation to designated Municipality municipality roads sections Drainage DEINFRA - Announcement of attention/ alert Basin by bulletin board of the road - PtifPreparation for emergency measures Each SDR Announcement of the attention/alert to state schools Instruction of temporary close of schools, return home or staying at the schools. Example of landslide risk map Overall Management: Defesa Civil-SC Feasibility Study of Priority Projects for Flood Prevention and Mitigation ■ SELECTION PRIORITY PROJECT Utilization of Existing Hydropower Dams for Installation of Floodgates and To achieve the 50-year flood safety level, a lot of cost and long period of Flood Control Improving Itajai Mirim River implementation will be necessary. It is important to implement step-wise gradually increasing safety level with priority projects including the non-structural measures. The 10-year flood level might be recommended for the target safety level of the first phase, considering the budget of the State Government. The priority flood prevention and mitigation measures for feasibility study were selected as follows: - Water storage in paddy fields - Heightening of existing flood control dam and modification of operation (2 dams) - Utilization of existing hydropower dams for flood control (2 dams) - Strengthening existing flood forecasting and warning system (FFWS) - Installation of floodgates and improving Itajai Mirim River in Itajai city Heightening of Existing Flood Control 589.6 652.2 Constant Gate 589.5 652.0 Opening Operation Inflow=Outflow 589.4 651.8 Inflow ( keep water level at EL.589.5m) Dams and Modification of Operation (m) Level Level (m) Inflow=Outflow =Outflow 589. 3 651. 6 589.2 651.4 Inflow=Outflow Prerelease Prerelease 589.1 651.2 (keep water level at EL.652m) 0.5m 1.0m Constant Gate 589.0 Water Level 651.0 Opening Operation Water Level Reservoir Water Reservoir Water588.9 650.8 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Da y Day Floodgate at Upstream Rio Bonito Dam Pinhal Dam 140.0 inflow 140.0 outflow from Rio Bonito Dam Maximum inflow 125 m3/s 120.0 120.0 Flood control Strage Flood control Strage 3 3 3 3 3200 x 10 m 100. 0 1400x101400 x 10 m 100. 0 3 45m /s 3 3 Maximum outflow 85 m /s /s) Maximum inflow 85 m /s 3 /s) 80.0 3 80.0 25 m3/s Initial 65 m3/s 60.0 Maximum outflow 60 m3/s 60.0 Discharge (m Discharge