Lao Mekong Pak Beng Hydropower Project Table of content Project - PowerPoint PPT Presentation

Lao Mekong Pak Beng Hydropower Project

Table of content • Project Brief • Hydrology • Sedimentation • Geology and exploration • Design Layout • Dam safety • Fish Pass facility • Navigation • Water quality • Sustainable Operation and Management 2

Project Brief CHARACTERISTIC OF PROJECT INSTALLED CAPACITY 912 MW NUMBER OF UNITS 16 47.65x10 8 KWh AVERAGE ANNUAL OUTPUT ANNUAL OPERATING HOURS 5225 h TONNAGE OF SHIP LOCK 500t 3

Project Brief • MOU signed August 2007 • FS Report (FSL 345m, installed capacity 1230MW) December 2008 • PDA signed December 2012 • ESIA approved by GOL March 2014 • FS Report (FSL 340m, installed capacity 912MW) July 2014

2 Hydrology 5

Hydrology Meteorological data Analysis of Data natural Data collect Hydrological data assessment geography Hydrology survey Meteorological Climate condition elements Runoff Runoff characteristic Analysis calculate Design Flood Flood characteristic Rating curve ……. ……

Hydrology

Hydrology Hydrol rologi ogica cal data avai aila labl ble e Area （ km 2 ） Station Stage Flow Chiang Saen 189,000 1960-2014 1960-2014 201,000 Sop Kok 1972-1987 1972-1987 204,000 Chiang Khong 1972-2014 1976-1981 、 1985 、 1989-1990 、 1992- Pak Beng 218,000 2008-2014 1993 、 1999- 2006,2008-2014 Laungprabang 268,000 1960-2014 1960-2014

Hydrology Discharge Gauge Station A Gauge Station C Measurement 325 H （ m ） 320 315 Dischareg Measured in 2008 Discharge Measured in 2009 Discharge Measured in 2010 310 Discharge Measured in 2011 Dischareg Measured in 2012 Discharge Measured in 2013 Discharge Measured in 2014 305 Gauge Station B Gauge Station D 300 0 1000 2000 3000 4000 5000 6000 7000 8000 Discharge （ m 3 /s ）

Hydrology Rating curve of Gauge station D 345 H （ m ）  Rating Curve 340 335 330 Measure discharge 325 Rating Curve at D Gauge Station 320 Discharge Measured in 2008 and water level Discharge Measured in 2009 315 Discharge Measure in 2010 Discharge Measured in 2011 310 Rating Discharge Measured in 2012 Hydraulic Discharge Measured in 2013 305 Discharge Measured in 2014 curve formula 300 longitudinal and 295 0 5000 10000 15000 20000 25000 30000 35000 Discharge （ m 3 /s ） cross section Rating curve of dam site 水 345 位 （m） 340 335 330 325 320 315 310 305 300 0 5000 10000 15000 20000 25000 30000 35000 流量（m 3 /s）

3 Sedimentation 11

Sediment  Sedim iment ent inve vest stig igati ation on KHIDI have carried out sediment investigation from Yunjinghong to Luang Prabang hydrological station, river diagram shows in the picture. 12

Sediment  Sedim iment ent inve vest stig igati ation on Yunjinghong - Referenced sediment Adopted sediment Pakbeng Drainage area Main stream Branches transport modulus transport modulus Intervals of Damsite (km 2 ) (t/km 2 .a) (t/km 2 .a) (t/km 2 .a) Yunjinghong 149100 726 726 Nanban River 7679 747 750 Exit of Lancang River 163000 (Guanlei) 350 300 ～ 500 Chiang Saen 189000 250 Nam Ing River 9750 53 Namtha River 8990 156 Pakbeng Damsite 218000 Nam OU River 19258 233 (Muong Ngoy) 13

Sediment  Sediment Amount at the Dam site Sediment data of W sJing hydrological station Data assessment Sediment investigation of M s mainstream and tributaries Sediment Calculated formula of Sediment amount of Pak Amount Beng Dam Site Consider Natural US dam condition Suspended load: Suspended load: 37.99×10 6 t 142.68×10 6 t Bed Load: Bed Load: 4.28×10 6 t 1.034×10 6 t 14

Sediment  Sediment sampling Suspended load Bed load 15

Sediment  Sediment Deposition Siltation Incoming Siltation Sediment Losing Rate of Losing Rate of Period Sediment Amount Delivery Storage below Normal Effective (10 6 t) (10 6 t) Rate (%) Water Level (%) Storage (%) (Year) 0 0 0 5 195 42 78.59 5.15 0.49 10 390 81 79.22 9.77 1.23 15 585 117 80.03 13.87 2.11 20 780 148 81.07 17.35 3.05 30 1171 191 83.66 22.15 4.72 40 1561 224 85.64 25.72 6.06 50 1951 252 87.10 28.62 7.16 60 2341 272 88.36 30.77 8.07 70 2732 224 89.48 32.21 8.73 80 3122 298 90.44 33.27 9.30 90 3511 307 91.26 34.06 9.80 100 3901 314 91.95 34.69 10.24 16

Sediment  Sediment Deposition This shows the siltation thickness changes. Siltation thickness in front of the dam increase year by year when the power station putting into operation. 17

Sediment  Sediment Flushing In order verify the flushing effect of the discharging sluicing gates, we simulate the Siltation thickness changes in the front of the dam before and after the gates open. Plant operation for 5 years Plant operation for 5 years before discharging gates open after discharging gates open 18

Sediment  Model test Sediment before Sediment before powerhouse discharge sluices 19

Sediment  Reservoir Operation Mode 20

4 Geology and exploration 21

Geology and exploration Catalogue of Strong Earthquakes  Earthquake safety with Intensity ≥V Degree Occurred in the Project Area Earthquake Earthquake No. Place name Magnitude intensity in the time project area Ⅴ 1 19251222 Laos 6.8 Ⅶ 2 19340212 West Laos 6 At the border Ⅶ 3 19350513 6.5 between Thailand and Laos Ⅴ 4 19370921 Northwest Laos 6 Ⅴ 5 19961221 Thailand 5.6 Ⅴ 6 20000119 Laos 5.8 Ⅴ 7 20000331 5.4 Laos Vieng Phoukha, Ⅵ 8 20070516 6.6 Laos Northeastern Ⅴ 9 20110324 6.8 Myanmar 22

Earthquake From the above maps, Orange area corresponds to Severe zone Yellow area corresponds to Middle zone 500 Green area corresponds to Moderate zone Km water and blue area corresponds to Minor zone Nam Ngum 0.03 (Moderate Zone) Source : International Seismological Centre (U.K.) Nam Leuk 0.10 (Moderate Zone)

Geology and exploration  Earthquake safety Seismic Dynamic Parameter Values of Bedrock in the Project Area 100-year 50-year exceeding Designed seismic exceeding probability dynamic probability parameter 10% 5% 2% A max (gal) 154 209 365 β 2.0 2.0 2.0 T g (sec) 0.25 0.25 0.25 a h (g) 0.157 0.213 0.372 24

Geology and exploration  Exploration (Rock mechanics test) 25

Geology and exploration  Exploration (Drill core) 26

Design Layout Project Layout Fish way lock powerhouse discharge sluice 27

Design Layout  Powerhouse Number of Units 16 Type of unit bulb Unit capacity 57MW Total capacity 912MW Height of plant 64m Length of plant 410m 28

Design Layout  Discharge sluices Number of sluices 14 Type of weir broad-crested Size of gates 15m × 23m Elevation of weir 317m Energy dissipation hydraulic jump Operation opened and closed in dynamic water 29

Design Layout  Ship lock Number of steps 1 Max. tonnage 500t Max. working head 32.38m Size of chamber 120m × 12m × 4m 1.5×10 6 t/year Total tonnage 30

Design Layout  Fish way Length 1.6km Slope 1.85% Width 10m 31

Dam safety  Safe passage of flood Flood Release Structures Check flood 8 sand outlets, size 30200m 3 /s 2.5m×5m Design flood 14 sand outlets, size 26800m 3 /s 15m×23m 32

Dam safety （ Construction ）  Cofferdam safety  First-Stage Diversion Structures include dry season cofferdam, longitudinal concrete cofferdam and R/B upstream and downstream transversal cofferdams .  protection against 20 years return period flood with discharge of 18,700 m 3 / s  Construction period of First stage foundation is 33 months, ranging from January of the Second year to December of the fourth year. 33

Dam safety （ Construction ）  Cofferdam safety  Second-Stage Diversion Structures include longitudinal concrete cofferdam ,L/B upstream and downstream transversal cofferdams  protection against 50 years return period flood with discharge of 21,100 m 3 / s  Construction period of Second stage foundation is 33 months, ranging from December of the fourth year to August of the seventh year. 34

Dam safety （ Construction ）  Cofferdam safety • The slop Stability and seepage stability of the first-stage and the second stage cofferdam have been calculated. The results show that they can meet the specification requirements. USACE Slope Stability EM_1110-2-1902 35

7 Fish Pass facility 36

Fish Pass facility  Fish investigation Dam site 6 stations for survey, sampling and Keng lae Ban Hom Pak Beng Xai observation Ban Luang Houay Tong Kan Ban Pak Ngua 37

Fish Pass facility  Design Principle 4 1 5 2 3 Upstream Fish Fish habits and investigatio target fish investigatio Monitoring downstream migration n n design 38

Fish Pass facility  Design Consideration( Upstream migration) Fish way Navigation lock( part) 39