Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

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A Partne r 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

description

by F. Kizito, E. Obuobie, J.P. Venot, C. Le Page and W. Daré Presented at the Final Volta Basin Development Challenge Science Workshop, September 2013

Transcript of Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Page 1: 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

Page 2: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Presentation outline1. Key message2. Background and Purpose3. Methodology4. Findings5. Lessons 6. Recommendations

Page 3: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

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

Page 4: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

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

Page 5: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Background

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5Nangodi on Red Volta

Yarugu on White Volta

BANSI BAWKU

TILLI

BIDURI

BINABA

TIMONDE

KOSANABA

WIDENABA

NAFKULIGA

ZONGOYIRI

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±0 7 14 21 283.5

Kilometers

V4 Watershed

5 V4 Communities

White Volta Basin Boundary

_ Small reservoirs

#* Flow Stations

Rivers

Page 6: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Methodology

Hydrological modeling

GEOSFM

Wet season Dry season

Participatory methods

Page 7: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Findings

Page 8: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Findings

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Page 9: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Findings

Major contribution: Upstream catchments

Page 10: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Findings

- NE portion is most vulnerable- Highly linked to landscape

attributes

Page 11: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

Andes • Ganges • Limpopo • Mekong • Nile • Volta

Findings

- With vegetative buffers in place- Erosion reduction by up to 15%

Page 12: Targeting interventions to reduce catchment sedimentation sub watershed in the White Volta basin

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