Nature based solutions as regional initiative towardsustainable river basin development
From DPRI Japan:
Prof. Tetsuya Sumi
A/Prof. Sameh Kantoush
Dr. Doan Van Binh
June 14-17, 2021

From TLU Vietnam
A/Prof. Nguyen Canh Thai
Dr. Pham Hong Nga
Dr. Truong Hong Son
Dr. Dinh Nhat Quang
Mrs. Nguyen Phuong Mai

TLU and DPRI collaboration under JASTIP:
reflection of Phase 1 & direction of Phase 2

Expertise exchange: workshop, field trips
Joint research, Lab establishment
Joint publication
Capacity building: PhD supervision, post doc
Student exchange

Joint activities in at TLU’s Hanoi campus

MOU Signing

Visitingmaindrainage
sluice gate
Bac Hung Hai Irrigation system in the RedRiver DeltaJoint activities in at TLU’s Hanoi campus• International Workshop on Sedimentation Management Sep
2019: participants from academic organizations,hydropower sector and government authorities from 4countries (Japan, Vietnam, Laos, Netherlands and France).
• Field trip in Vu Gia Thu Bon basin to prepare future research
proposal• Working closely with lined agencies of Vietnam andinternational donors

Joint activities in at TLU’s HCMCity campus
Kyoto University’s office at
Thuyloi University, Vietnam

Instrument installations

Data collection at monitoringstations
Salinity collection at AnLacTay station

Turbidity collection at VamNao station

Suspended sediment concentation at
VamNao station

250 mg/l

Joint activities in at TLU’s HCMCity campus

Annual International exchange course“Conflict Management (Global Water Issues)”

Ongoing research initiative under JASTIP –Nature based Solution(s) (NbS) to river bank protection
and long tern resilience• Mekong Delta

Vu Gia Thu Bon BasinWater resource and its role in socioeconomic development in Vietnam
 Dense river basin network throughout the country.
 Annual rainfall: 1,500mm  2,000mm, out of which
80% concentrates during July to October.
 Over 3400 km of coastline.
 63% of water resources is originated beyond theborder.
• Role of water resources in Vietnam: denselyorganised around two deltas: Red River in the North, Mekong in theSouth; vital resource for all development sectors and population
growth:- 30 years of uninterrupted GDP growth GDP x 10 (from $23 to $ 230 billion, average annual growth of 6%), poverty rate decreasedfrom 58% in 1993 to 6% in 2020.
-High demographic growth (from 62M in 1986 to 96M in2018), urban population x 3 (11M in 1986 to 33M in 2018) and young

Main river basins in Vietnam

Vietnam is facing serious environmental
challenges
Critical consequences:• Subsidence of ~2cm / yr, increasing risk ofpermanent inundations• Flash flood and inundation are more frequent andextreme• Coastal erosion• Drought episodes (groundwater at its lowest level
since 1926 !)• Increase of the soils salinity, up to 100 km upstream

Typhoon tracking chart (1988-2017)

River bank and coastline erosion

Dien Hoa commune, Dien Ban DistCua Dai beach, Hoi An

Embankment along Cu Lao Cham coastline

Sedimentation issues

No sedimentation measurement at Song Tranh
2 Dam (2010, CAP:729MCM)
Uncontrolled sand mining

Uncontrolled coastal development tointerrupt natural longshore sedimenttransport

The Mekong Delta - Initial result
Causes and drivers: Subsidence, land use changes, sea level rise etc.
Effect: Mangroves lost and coastal erosion.

Initial result -The Mekong Delta - Initial result
Experiment set up

Vu Gia Thu Bon (VGTB) basin• Serious coastal erosion in the central coast in Vietnam• Large dam catchment area and Sand mining in Vu Gia-Thu Bon river
may cause decrease of sand supply from river estuaryUpstream dam and reservoir cascadeSerious erosion in the downstream

Cua Dai Beach in Quan Nam ProvinceProposed initiative approach for VGTB: Mangrove restoration as nature-based solutions
to riverbank protection
 Practiced oriented study approach and follow up
based on strong partnershipRESEACHERS –TLU, DPRIPOLICY MAKING and DONOR:
Ministry of Agricultre and Rural Development,
local authority

PRIVATE SECTOR:

dam owner, environmentalist group2

Demonstrating selected NbS
Permaculture / On-shore
Sustainable Farming
will consolidate riberbank/ coastal shoreline.

The erosion issues identified by scientists focused mainly on water
courses/currents and sedimentation matters, however, the quality of soil
profile/structure of riverbank/shoreline also depends on the way humanbeings do farming that has impacts on the root’s structure of vegetation,consequently on the quality of soil structure – the factor plays animportant role in resilient and adaptive capacities of the ecosystem.
Permaculture or sustainable farming on-shore will be a decisive andsustainable solution.

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Non-structural Techniques:Bio-logs
Bio-logs (coir & fiber logs, bamboo or live-stakesblankets)
This amazing technique combines plantings with erosion-control
products made of natural, biodegradable materials, such as fiber or coirlogs and fiber blankets. These logs are made of compact fiber wrapped ina netting to hold the fiber in place. The biodegradable logs are placed
closely along shorelines, typically staked into place to prevent being
moved by waves and currents, and will naturally assimilate into thesurrounding habitat over time (usually between 1 and 2 years dependingon the density and type of fiber used). They are used to temporarily
contain soil or sand fill and protect the shoreline until planted sites
establish root systems and become stabilized.
This technique is most effective for salt marsh restoration and protectionin the face of storms and sea level rise. It is best in sites that are relatively
protected from boat wakes and waves. Other considerations when using
bio-logs include constructing the logs to hold up to wave energy and tidal
elevations, as well as ensuring marsh grasses are at an optimal height
above water.

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5Cam Kim (Hoi An) riverbank after 2 years of applying this hybrid NbS

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6

Management issues

1985

2021

2

Management issues

2014

2021

2

Squeeze2

Tools• Nearshore wave
transformation• Wave – vegetationinteraction• Suspended sediment

Cu Lao Cham

SWASH
Quang Hue

DELFT3D

Cẩm KimSWAN•

Offshore wave
transformation

DELFT3D + SWAN

• Flow – vegetationinteraction• Bed load & Suspendedsediment• Flooding3

Predictive model with vegetation

CanopyStemRhizophoraceae

ModelRoot31

Main Objective & Data Collection• Build Eco-Morphodynamics model•
•••••
••

Bathymetry (d)River discharge (Q)Water level (H)Waves (W)
Flow (U)Sediment (S)Vegetation characteristics
Other data: sediment load, annual
dredging, Precipitation (P),…

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Next steps• TLU is keen to continue fruitful collaboration with DPRI and ASEAN partners
on this initiative, e.g sharing experiences and case studies, student
exchange etc.
• Continue to work closely with practical partners to demonstrate research
results in practice to make the tangible impacts on the ground.
• Recommendation for roll out