How hydropower operations can accommodate local livelihoods
1. How hydropower operations can
accommodate local livelihoods?
Presenter: Guillaume Lacombe
Synthesis of results from two interlinked studies:
Evaluating Land and Water Resources available to communities living around
reservoirs in the Mekong Basin: case of the Nam Gnouang reservoir in Lao PDR
Kam SP, Teoh SJ, Metzger L, Hoanh CT, Reis J, McCartney M, Lacombe G
Adjusting hydropower dam operation to complement livelihood strategies in
the Lower Mekong Basin
Reis J, Culver T, Lacombe G, Hoanh CT, Keophoxay A, Douangsavanh S, Teoh
SJ, Kam SP, Sellamuttu SS
Third Mekong Forum on Water Food and Energy
19-21 November 2013 - Hanoi, Vietnam
2. Key messages
• Livelihoods constrained by several factors:
– Steep slopes, protected areas, travelling cost
• Altering dam operations to complement
livelihoods is not realistic in the studied site
• Better to adapt to new hydrological reality
that prioritizes generation of hydro-electricity
– constructed wetlands for fisheries and irrigation
• Today’s livelihood sustained by lacustrine
fisheries. And tomorrow ? Off-farm activities?
3. Case of the Nam Gnouang storage reservoir
Keosaenkham
Nam Gnouang Dam
Typical cross section
Seasonal
variations of
flooded area:
15 – 105 km2
4. We use a Decision Support System (DSS) tool to
answer the following questions:
1. How affected communities can best use land and
water resources under new resettlement conditions ?
2. Can reservoir operation rules accommodate livelihood
needs while preserving hydropower generation ?
a) Recession agriculture on seasonally-exposed garden in
draw-down areas of reservoir
b) Fish resources enhanced with constructed wetlands
Modeling, simulations and optimization to explore
options
5. A suite of modeling and simulation tools
Land use planning & analysis system (LUPAS)
To explore cost-effective options of livelihood
activities based on available land and labor resources
Examine the interaction between reservoir operation & livelihood opportunities
Reservoir model (HEC-ResSim)
To simulate & optimize dam operation
(water level variations and hydropower
production)
GIS modelling
To evaluate accessibility to land
resources supporting livelihoods
(spatial analysis and mapping support)
6. HEC-ResSim
Lowering reservoir water level to allow dry season vegetable growing
(eggplant, chili and green vegetable)
A1 and A2 lower overall hydropower generation by 3% and 8%, respectively, allowing crop
production in limited area. Agricultural gains result in significant loss of power production.
Constructed wetlands for fisheries and small-scale irrigation
Connected or adjacent to reservoir. They would
- provide benefit to fishermen (full ponds year-round), potentially enhancing fishing
livelihoods,
- Provide water irrigation, even during dry years, for vegetable garden closest to village
7. Seasonally-exposed land analysis
1 Exposure period
2 Slope suitability
3 Physical access
Least
Least
Most suitable
Most suitable
30%
50%
Water body
20%
Weighted linear
combination of factors
Water body
GIS
modelling
Overall
suitability for
recession
agriculture
KSK
8. (land-use planning and analysis system)
$1,800
$1,700
$3,600
Community
Household
LUPAS
$2,300
Year 1
$2,300
$4,000
Year 2
When fish available, shoreline farming has little effect on net gain,
Expected fish decline (eutrophication): need for farm productions diversification,
Pilot program (irrigated gardens) allows flexibility in livelihoods and increases net gain,
Sharing resources is the most important factor for increasing the overall net gain.
Year 5
9. Conclusion
• Uncertain future/expected fish decline &
limited land and water resources→ need for
diversification in off-farm activities,
• Important to consider replications of this
study in areas with larger affected population
Editor's Notes
This presentation summarizes the work done in the DSS component of the MK1 project which explores how hydropower reservoir operation and management can accommodate local livelihoods.This research was conducted as part of two interlinked studies.- One focused on quantifying accessibility of land resources to villagers,And the other one looked at alternative hydropower reservoir operating options to complement livelihood strategies.
1/ Our case study is located in a mountainous area and slope steepness significantly reduce farming opportunities.Part of the surrounding forest and lakeshore are protected and it not possible to access to these areas
NG dam built in 2010-11 to double capacity of the downstream Theun-Hinboun extension dam after inflow from Nam Theun River was reduced because of NT2 dam. 15-105 km2, huge seasonal variations of water level and flooded area.4 upstream villages were resettled into one village that is our case study site.
Question:ANALYSING HYDROPOWER RESERVOIR OPERATION AND MANAGEMENT OF RURAL LIVELIHOODSHow reservoir management may accommodate fishers and farmers in resettled villages for farming on the banks and diversify fish habitat.
Lower water level during cultivation period to expose shoreline gardens during longer period to match crop calendars/Constructed wetland adjacent and connected to reservoirs to enhance fisheries How to allocated resources to maximize net gains, between various activities including fisheries, rice farming, vegetable gardening, NTFP collection, extensive livestock)
GIS-based analysis was carried out to determine and mapseasonally-exposed land for recession agriculture:Three factors are taken into account:1.The exposure period of the seasonally-flooded land – this is based on the results of the ResSim modeling of water level fluctuations in the reservoir. The fluctuations vary from year to year, rating is done based on average exposure period over a 12-year simulation period (1999-2010)2. The slope steepness, based on the 30-m DEM 3. Physical accessibility to the seasonally-exposed land – this is modeled using GIS accessibility analysis to map the cost distance (i.e. difficulty of travel), taking account of boat travel up-river (slower speed) and down-stream into the reservoir (faster speed) from the Keosaenkham fish landing site.Based on the focus group discussions with villagers in August 2012, unequal weights are assigned to the three factors in the conducting the multiple criteria evaluation using weighted linear combination of factors. The area extent of the “water body” is the 420masl elevation, which is taken as the lowest water level to be reached with the NG dam in operationThe overall suitability map shows there are potentially more areas downstream from KSK village suitable for recession agriculture. However substantial parts of may not be available for reasons indicated in the slide. Furthermore it would probably take a number of years more for the reservoir operation to regularize and the water level fluctuation to be more stable before the villagers will have confidence to commit to recession agriculture in new areas. Presently many of them still go upriver to farm at their former village locations where they are familiar with the soil and water regimes. It should be noted that there are stretches where the grid cells immediately adjacent to the river are rated unsuitable even though those further back are rated suitable (as pointed out in the inset map, zoomed in on the part of the river between Keosaenkham and Saensi). Would this mean that areas further in from this “unsuitable” rim may not be all that suitable after all? One obvious case we are familiar with is the area at the KSK fish landing site where the immediate bank of the river at the low water level may be too steep. Created on: 02 Nov 2012
household- or community-level optimization (resources shared),5-year periodmodel excludes non-agricultural and non-fishery activities.Geospatial analysis previously described was used to account for farming areas and travel cost.Accounting for farming areas created by THPC to prevent deforestation and protect access to the reservoir,Accounting for seasonal variations of fish productivities.Net gain calculated by optimized model should be compared to company-set income target of 1,813 USD/householdModel = resource allocation model (linear programming)Model optimizes labor allocation measured in man-days1 household = two adults full-time workers5-year baseline.Account for cost and time related to distance, fish availability, labor hired, 5 experiments: steady fish response, food security, irrigation pilot, high water (above 75th percentile) and community level (labor and investment shared among households).