David Corderi Novoa

Department of Agricultural & Resource Economics

University of California – Davis, United States

In collaboration with:

Jeffrey Williams1, Jay R. Lund1, Richard E. Howitt1 and Do Duc Dung2

1 University of California Davis – United States2 Dong Nai River Basin Planning Commission, Southern Institute for Water Resources Planning (SIWRP) - Vietnam

Motivation

Studies of adaptation in different scales of analysis such as economy/sector-wide but not at the River Basin Level.

Studies at river basin level do not fully incorporate economic analysis for decision making (more details on biophysical aspects)

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Previous Studies…

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Expected Impacts

Economic analysis to inform decision making at river basin level.

Incorporating Autonomous (water user) and Planned Adaptation (government) at the River Basin Level

Focus on Hydrological Extremes (Dry Season and Wet Season Changes)

Economics of Uncertainty (risk based CBA, real option analysis)

Timing and Sequencing (beyond static scenarios) of Adaptation

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Project Design Climate Change Projections

Rainfall/Runoff + Hydrodynamic Model Projections

Adaptation Dry Season: Salinity Changes(focus on agriculture)

Adaptation Wet Season: Flooding Changes(urban and rural areas)

Economic Model Risk-Based Optimization (Flood Infrastructure Investments

Economic Model Water Infrastructure and Agriculture Production

RISK Probability Consequences

Identify Climate Change Impacts

Identified Adaptation Options

Jonkman et al. 2008Moser 1997

Crop Cost & Return Studies

Agriculture Land Use Plans

AgronomicSalinity-yieldField Exper.

Water Infrastructure Plans (Cost & Benefits)

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Study Area: Lower Dong Nai DeltaThe Map of Vietnam

Ha Noi

Ho Chi

Minh City

Dong

Nai RB

Mekong

Delta

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Dong Nai Basin Facts

Characteristics:

- Population: 18 million (20%) - Area: 55,439 km2 (17%)

- GDP~48% of National GDP*

* 28% Agriculture/ 63% Industry/41% Services

- River Basin Organization (DNRBO, created in 2001)

Previous studies:

Economic model for water allocation (Ringler 2004)

Irrigation, flood control assessments, water resources planning.

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Current Dry Season-Salinity

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Current Areas Experiencing Flooding

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Da D en Res er .

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Tu yen La m Res er .

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BA R IA

DA TEH

CU C HI

DA LA T

LAM HA

HA M TA N

DI LINH

BAO LAM

BAO LOC

DA HOAI

TA N PHU

GIA RA I

BU DANG

BEN C AT

DUC H OA

CA N GIO

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LONG D AT

DUC LI NH

XU AN LO C

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LOC N INH

TA N BIE N

TA Y N INH

PH UO C LY

TA N UY EN

VINH C UU

THU AN A N

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VUNG TAU

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CHAU DU C

XUYEN M OC

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BINH LONG

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TUY PHON G

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DON DU ONG

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CHAU THANH

TR ANG BAN G

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THONG NHATPHAN THIET

NI NH P HUOC

LIEN K HUO NG

HA M TH UAN NAM

HA M THU AN BA C

DUONG M IN H CHAU

HO CHI MI NH C ITY

Lower Da Nhim reservoirMiddle Dong Nai river

Lower La

Nga riverLower Dong Nai-

Sai Gon rivers

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Progress so far…

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Climate Change Impact & Adaptation Assessment

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

90,000

1 3 5 7 9 11 13 15 17 19 21

Lan

d V

alu

e (

mill

ion

VN

D)

Salinity Concentration (g/l)

Region 1

Region 6

Region 5

Region 7

Region 8

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2,000

4,000

6,000

8,000

10,000

12,000

1 4 7 10 13 16 19 22 25 28 31

Cro

pp

ing

Pat

tern

s (h

a.)

Salinity Concentration (g/l)

W-S Rice

S-A Rice

Sugarcane

Vegetables

Investment Timing and NPV

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Identified Adaptation Options

Be

Riv

er

La

Nga

Riv

er

Dong Nai River

Don

g N

ai R

iver

Tri An

Dau

Tieng

Thac MoDa

Nhim

Can Don

Ham Thuan

Sai Gon River

East V

am C

o River

West Vam Co River

Dai Ninh

SRFu

Mieng

Constructing Sluice Gates Changing Cropping Patterns

Changing Upstream Reservoir OperationConstructing/Upgrading Dykes

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Main Questions How the Dong Nai Basin Can Adapt Economically to

changes in the Dry Season?: Tradeoffs between changing cropping patterns, changing

reservoir operations and the timing of “irreversible" infrastructure investments to maintain agricultural productivity.

Sea level rise, trade-offs between protecting downstream coastal areas versus upstream.

How to re-design flood protection infrastructure in a context of changes in flood frequency and increasing urbanization and value at risk (what areas to protect?, when?)

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Project ChallengesData availability and data quality

(weather stations, gauge stations)

Wilby and Dessay 2010

Uncertainties at all levels (simplification)

Integrating different temporal, spatial scales, units of analysis (RB, admin units)

Collaboration among experts of different backgrounds

Lund et al. 2010

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Lessons Learnt Despite data limitations, results from analysis can be useful for

river basin planning.

Changes in hydrologic extremes have more implications than changes in average hydrology when planning for adaptation.

Economic analysis can be useful for decision making at the river basin level:

Analyze tradeoffs inherent to investment planning.

Suitable to analyze uncertainty, timing and sequencing of adaptation

It is not the only approach… (MCA, etc.)

Collaboration between multi-disciplinary teams (economists, hydrologists, engineers,…) builds capacity (integrative approaches and common understanding)

Transboundary coordination is also important for RB planning.

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Thank You & Discussion

More from: David Corderi (dcorderi@primal.ucdavis.edu) et al.:

“The Economics of Climate Change in River Deltas: Adapting to Increased Salinity.” forthcoming in Proceedings of the 17th ISDRC Conference,

“Moving Towards a Sustainable Future: Opportunities and Challenges.” May 8-10, 2011, New York, United States.

“The Economics of Climate Change, Urbanization and Long Term Flood Protection in the Lower Dong Nai Delta.” forthcoming in Proceedings of

the KLIMA 2011 Conference, “Climate Change and Disaster Risk Management.” November 7-12, 2011, Bonn, Germany.

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Extras…

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Planned Sluice Gates

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Planned Dykes

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Cropping Calendar and Crop Water Demand

Crop Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total (m3/ha)

Winter-Spring Rice 2653 2537 2683 912 0 0 0 0 0 0 0 2239 11023

Summer Autumn Rice 0 0 0 0 1731 1843 1377 1611 477 0 0 0 7038

Seasonla rice (single rice) 596 0 0 0 0 0 0 0 1146 1249 1487 2314 6792

Winter-spring upland crop (Maize, soybean, bean,…) 2766 1288 0 0 0 0 0 0 0 0 644 950 5648

Summer-autumn upland crop (Maize, soybean, bean,…) 0 0 0 0 909 2809 124 529 0 0 0 0 4370

Seasonal upland crop (Maize, soybean, bean,…) 0 0 0 0 0 0 0 172 1120 44 505 0 1841

Winter spring vegetable 2003 1136 0 0 0 0 0 0 0 0 448 1138 4725

Summer- autumn vegetable 0 672 1459 2144 755 0 0 0 0 0 0 0 5030

Seasonal vegetable 0 0 0 0 0 0 340 767 1164 405 0 0 2676

Sugarcane 1384 1911 2084 1938 2057 1548 1350 1653 1121 1227 2274 1287 19832

Coffee/Peper 998 934 995 875 3194 336 286 798 423 549 643 998 11029

Fruits 998 934 995 875 3194 336 286 798 423 549 643 998 11029

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Salinity Dynamics

Salinity projections Seasonal Salinity

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Alternative Flood Control Strategies

Source: PPIC (2011)

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