Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin
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Transcript of Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin
A Partner of
Targeting interventions to reduce catchment sedimentation: The case of a sub-watershed in the
White Volta Basin
Kizito F., Obuobie, E., Venot J.P., Le Page C., and Daré W
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Presentation outline1. Key message2. Background and Purpose3. Methodology4. Findings5. Lessons 6. Recommendations
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Key message
- Study illustrates the relevance of distributed erosion models to target erosion control measures
- Illustrates the use of vegetative buffer strips to reduce erosion rates by 10-20%
- Importance of community involvement
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Background and Purpose
- Study area lies in the White Volta Basin - Coverage of sub-basin is about 2,400
sq.km- Major issues relate to climate variability,
poor soil functions, and reduced storage capacity of reservoirs
- Intervention: landscape management to reduce erosion and sedimentation
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Background
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#*
#*
5
5
5
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55
5
5
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5Nangodi on Red Volta
Yarugu on White Volta
BANSI BAWKU
TILLI
BIDURI
BINABA
TIMONDE
KOSANABA
WIDENABA
NAFKULIGA
ZONGOYIRI
0°0'0"
0°0'0"
11°0'0"N 11°0'0"N
±0 7 14 21 283.5
Kilometers
V4 Watershed
5 V4 Communities
White Volta Basin Boundary
_ Small reservoirs
#* Flow Stations
Rivers
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Methodology
Hydrological modeling
GEOSFM
Wet season Dry season
Participatory methods
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
19681970
19721974
19761978
19801982
19841986
19881990
19921994
19961998
20002002
20090.00
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600.00 0
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Rainfall Confidence band Observed Flow Simulated Flow
Disc
harg
e (m
3/s)
Rain
fall
(mm
)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
Major contribution: Upstream catchments
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
- NE portion is most vulnerable- Highly linked to landscape
attributes
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
- With vegetative buffers in place- Erosion reduction by up to 15%
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Recommendations
- Explore linkage with V1 on scaling out interventions
- Targeted interventions are context specific dependent on the biophysical characteristics as well as social dimensions
- Intervention need to consider associated environmental consequences, use of ecosystem based approaches would be appropriate