1. COASTAL EROSION IN MEKONG DELTA & PROTECTION SOLUTIONS
Thong NGUYEN et al.
Tel
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2. Assoc. Prof. Nguyễn Thống Dr. Hồ Tuấn Đức Dr. Lưu Xuân Lộc
MSc. Lê Ngọc Anh
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3. Overview & Methodology Region zone Local & study zone
CONTENT
Overview & Methodology
Region zone
Local & study zone
Results and discussions
Perspectives & Conclusion
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4. 1. OVERVIEW & METHODOLOGY
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5. Research group was involved in:
Work package 4.1: Wave calculation in regional and local zone for U Minh, using TOMAWAC module;
Work package 4.2: Calculation of coastal currents in regional and local zone for U Minh, using TELEMAC (driven by wind, wave, tide and flow from estuary)
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6. Work package 5.2: Hydrodynamic model for studied area in U Minh
Work package 5.1: Simulation of suspension and sediment transport at Mekong Delta’s estuaries and coastal area near Cà Mau-U Minh (TELEMAC + SYSIPHE).
Work package 5.2: Hydrodynamic model for studied area in U Minh
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7. Work package 5.3: Understand the erosion process at coastal area of U Minh-Cà Mau by numerical model.
Work package 6.2: Evaluate the shore protection works by using TELEMAC + SYSIPHE
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8. METHODOLOGY
Numerical model.
Hydrodynamic model for southern area of East Sea: Telemac2D + Tomawac (region zone).
Hydrodynamic model & morphology for local & study zone: Telemac2d + Tomawac + Sisyphe.
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9. Study zone COASTAL AREA IN THE DOWNSTREAM OF MEKONG RIVER (LMDCZ) 9
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10. (region zone) 2. COASTAL AREA IN THE DOWNSTREAM OF THE MEKONG RIVER
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11. Study zone: Region zone
Vũng Tàu
Vĩnh Long
Cần Thơ
Cà Mau
elements
Max = 9km
Min = 8m
Coastal = 250m
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12. BOUNDARY CONDITIONS
East Sea
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13. Bathymetry & bound. cond.
- Coastal: SIWRR
- Offshore: ETOPO1 with x=900m.
Liquid bound.: Astronomical tide from TPXO with 9 main tides:
K1, O1, P1, Q1 , S2, N2, K2, M2 và M4.
Wind, wave: Data from NOAA.
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14. Model calibration & validation
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15. Wind (1-2014)
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16. Wind (8-2014)
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17. Boundary Q1 & Q2 (1-2014)
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18. Tidal boundary (1-2014)
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19. Wave boundary HM0 (1-2014)
T (ngày)
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20. Wave boundary HM0 (8-2014)
T (ngày)
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21. TRẦN ĐỀ
Tidal (  )
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22. GÀNH HÀO
Tidal (1/1/2014  15/1/2014)
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23. RẠCH GIÁ
Tidal (1/1/2014  15/1/2014)
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24. Preliminary results
Hydrodynamics
Wave
Sediment transport
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25. Mean velocity field (1-2014)
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26. Mean velocity field (8-2014)
Site U Minh
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27. Mean velocity field (8-2014)
Local U Minh
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Animation: SIWRR_Hydro.avi

28. Comments
Mean velocity field in January 2014 is quite large comparing to that in August 2014
Formation of coastal currents toward the south during January 2014
Mean currents in August 2014 is minor.
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29. Wave field HM0 at 12H, 13/1/2014
Vĩnh Long
Cần Thơ
Cà Mau
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30. Average wave field HM0 in January 2014
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31. Wave field HM0 at 24H, 15/8/2014
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32. Average wave field HM0 in August 2014
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Animation: SIWRR_Wave.avi

33. Waves in Jan. 2014 tends to be larger than in August 2014.
COMMENTS
Waves in Jan tends to be larger than in August 2014.
Waves in the West tends to be intensified by Southwest wind.
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34. WAVE HM0(t) (1-2014)
HM0 (m)
T (ngày)
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35. WAVE HM0(t) (8-2014)
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36. COMMENTS
In Jan. 2014, NorthEast wind is dominant  waves in East Sea are intensified.
In Aug. 2014, SouthWest wind is dominant  waves in East Sea are reduced.
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37. 5. RESULTS & PERSPECTIVES
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38. Southwest winds intensify the waves in the West Sea.
CONCLUSIONS
Wind direction affects significantly the distribution of wave intensity in the East Sea and West Sea.
Southwest winds intensify the waves in the West Sea.
The sediment transport rates are important in estuary area and in the main rivers in Mekong.
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39. In addition to the sediment from the upstream of the Mekong river, the sediment transport due to morphology changes also plays an important role.
The coastal erosion / acrreation rate at U Minh is less than in other areas.
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40.  Hydraulic regime in the West Sea is quite complex.
Simulation results and observation are quite different.
could be the complexity of bathymetry and tidal conditions.
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41. Develop the own grid system for U Minh area.
WHAT TO DO NEXT ...
Develop the own grid system for U Minh area.
Simulation for the years with available flow and stage data (2015, 2016).
Impact assessment of mangrove and maleleuca fences.
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42. Update and complete the coastal bathymetry.
WHAT TO DO NEXT ...
Update and complete the coastal bathymetry.
Simulation of shore protection works: semi-submerged groyne.
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43. THANK YOU for your attention!
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