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SUSWA GULLY CONTROL AND
REHABILITATION IN NAROK COUNTY
Dr P.T.Gicheru
ECONOMICS OF LAND DEGRADATION NATIONAL CONSULTATIVE WORKSHOP
Nairobi, 15 April 2014
Introduction
Narok District has an area of 15,088 km2 located in SW Kenya
Two zones: the highland over 2,300 and lowland 1000 - 2300 meters ASL
Highlands have rich volcanic soils good for intensive agriculture with large-scale farms
Lowlands have high potential for livestock rearing but fragile soils and unreliable rains.
Have Nomadic pastoralism and small-scale subsistence farms
Land degradation Loss of land cover Soil erosion Lack of enough and good quality water
Reduced water catchment areas Reduced soil nutrient availability Polluted water bodies
From 1980 - 2007, soil erosion rate increased from 50% to 80%,
Water availability reduced from 90% to 55% in Suswa
Consequence-reduced crop and livestock productivity
Land Privatization Policy, the Wildlife and Tourism Policies
Land Privatization Policy has changed the land tenure system to private ownership
It has facilitated the immigration of people from other areas
Pastoralism moved to more marginal areas Wildlife and livestock pasture land lost to
agricultural production The local people benefit little from
agriculture and wildlife
Policies as drivers to LD
Indicators
Environmental indicators for land degradation
Reduction of forested areas High amount of soil lost thro erosion Number of Rills and Gullies increased Negative soil nutrient balances Poor water quality
Economic indicator Low household Incomes
Social IndicatorFood insecurity – low average staple food consumption/farm household/year
Drivers of Land Degradation
Population growth rate Increase of off-farm income/annum Land sub-divisions of less than an acre Overstocking and free range grazing
systems Encroachment of forests and water
catchments for settlement Charcoal burning as source of livelihood Inadequate soil conservation measures and
minimum planting of trees. Lack of land proper land use policies
Opportunities On-farm soil and water conservation and
riverbank protection by pegging, tree planting, fallowing and fencing – off the main waterways that are practiced to counter the effects of environmental degradation
Capacity building of farmers on benefits of soil and water conservation.
Take conservation programs to farmers e.g. woodlot establishment, agro-forestry, drip irrigation, soil conservation structures, roof water harvesting and riverbank protection
OLESHARO (SUSWA) GULLY EROSION CONTROL -A CASE
STUDY
Olesharo gully
Train the local community and extension staff in gully control and rehabilitation.
Conduct baseline survey involving the local community in the affected area.
Determine the climatic, soil and land use characteristics that contribute to gully erosion and assess land use and land use cover change over the last few years using remote sensing and GIS.
Conduct resource mapping with the local community using participatory GIS (P-GIS) tools.
Design and implement gully control measures appropriate for the affected area.
Disseminate research findings (publications in scientific and popular journals, policy briefs, mass media, participation in local, national and international conferences and workshops)
The Major objective was to rehabilitate the Olesharo Suswa gully
Methodology
Approaches to gully control and rehabilitation
Identify the gully catchment and define the drainage pattern
Identify the source of runoff causing gully erosion Survey the profile of the gully Design gully control structures Implement construction of proposed structures Monitoring the gully healing progress
A meeting with stakeholders and gully control and structures
Results
Water Pan
Cutoff drain or diversion ditch constructed at the top end of the catchment above gully head to divert runoff from entering the gully.
Retention ditch and semi circular bund constructed within the catchment to hold runoff and reduce the flow to the gully. The runoff held in the ditches will increase soil moisture in the catchment suitable for re-vegetation and planting of trees. The ditches also act as soil erosion control measures.
STRUCTURE TARGET ACHIEVEMENT
Water pan One water pan with a capacity of 20,000 cubic metres
One water pan completed
Retention ditches 10,400 metres 16,300 metres
Semi-circular bands 400 metres 450 metres
Check dams(using gunny bags)
315 metres 450 metres
Check dams(using brushwood)
250 metres 360 metres
Brushwood strips 500 metres 750 metres
Cut-off Drains 280 metres 210 metres
Socio-Economic Impacts
Re-stocking livestock through purchase of 100 sheep, 2 cows and 20 goats
Construction of three small water pans of 100 cubic metres at household level by individual households
Paying school fees to their children and medical bills for some family members
Purchase of foodstuffs and clothing for the family
Over 5 small groups were formed by the casuals working in the catchment
Most of the members pooled up their proceeds from the work and contributed to members on a merry-go-round basis.
Soil and Water Conservation structures
Conclusion The rehabilitation of the Olesharo (Suswa)
gully was treated as phase I and the team has identified some other two areas (Phases II and III) which require to be rehabilitated urgently
Thanks for listening
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