1.2 Coordonnées des personnes-ressources et des institutions impliquées dans l'évaluation et la documentation de la Technologie

Nom du ou des institutions qui ont facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Soil Conservation, Land Use and Water Adminstratio (Soil Conservation, Land Use and Water Adminstratio) - Soudan

1.3 Conditions relatives à l'utilisation par WOCAT des données documentées

Le compilateur et la(les) personne(s) ressource(s) acceptent les conditions relatives à l'utilisation par WOCAT des données documentées:

Oui

1.4 Déclaration sur la durabilité de la Technologie décrite

Est-ce que la Technologie décrite ici pose problème par rapport à la dégradation des terres, de telle sorte qu'elle ne peut pas être déclarée comme étant une technologie de gestion durable des terres?

Non

1.5 Référence au(x) questionnaire(s) sur les Approches de GDT

2.1 Courte description de la Technologie

Définition de la Technologie:

Water Spreading (or Spate Irrigation system) conducted through the construction of earth dam structures at the khor cross section.

2.2 Description détaillée de la Technologie

Description:

Water Spreading (or Spate Irrigation) can be done through the construction of an angled bank or weir – with a spillway in case of excess flow – to divert a “khor” (ephemeral stream) and spread it (using spaced contour bunds) for crop production.

Water Spreading from khors or wadis where channelized runoff/ floodwater is diverted onto plains which are then cultivated on residual moisture. An example of a scheme which was constructed in 1999 is located at Hashitribab, some 7 km from Sinkat on the road towards Kassala. This scheme, comprising a stone-pitched earth diversion barrier across a khor (an ephemeral water course), is documented by using among others the WOCAT Questionnaire and WOCAT’s QA. While the diversion is still intact and provides water to the fields about one kilometre downstream (there were young sorghum plants growing at the time of the visit in November 2011) maintenance will be needed.
There was only a very small input of voluntary labour in its original construction (comprising a contribution in terms of stone pitching).

Construction by the Government, using machinery, with little local contribution might explain why voluntary maintenance of the structures has been negligible. Water spreading schemes have gradually expanded in number over the last 20 years in Red Sea State (according to Sayed Dabloub’s personal comment). Currently it was confirmed that there are new sites under planning and construction.

The purposes of diversion dam construction was to divert the main water course to take its way in the crop growing area replacing the old one and being controlled by small diversion dams (terraces to spread water for even water distribution through the original land. These terraces remarkably reduce gully formation.
Most important purpose is to provide water to growing crops in an area which is too dry for rain fed production and where no source for irrigation is available. It secures moisture during the growing season, by allowing more water to penetrate soil and to preserve moisture for a longer period at plant root zone.
The decrease of flood water velocity leads to silt accumulation and other debris materials which increase soil capability in providing moisture, nutrients and maintain soil structure and conservation.

For the earthen/stone-pitched diversion structure with spillway and small haffir alongside machines have been used (mainly loaders provided by the government) which excavated and built the bund. In addition local communities were involved in some aspects of the establishment (mainly stone pitching) supported/subsidized with incentives. The structure/scheme at Hashitribab (close to Sinkat) was built in 1999 (and no maintenance has been done since that time). It helps in watering about 500 feddan (c. 200 hectares) of agricultural area where water is spread by the use of small contour bunds: these were also constructed using subsidies and machines.
Terraces are usually used to control water spreading along the cropped area. Those terraces usually receive the water at low speed velocity. For that reason they are very small in size and volume. Usually they are located in very gentle and uniformed areas. The terraces can be constructed by simple hand tool and tractors accessories. But the prolonged drought makes the maintenance difficult as the dry soil is more susceptible to wind erosion and sand accumulation on both sides of the dam and the bottom of the bund is one of several desertification phenomenon in the region. But the wind-blown sand is one of the most serious one especially in the dry lands of the Red Sea State. Contour survey for land leveling slope identification and location is an important step before implementation.

The study site is located in the arid region of Red Sea State where steep hills from north-south inland mountains are interrupted by arid plains. The population density is low and the population depends on both cropping and livestock with high incidence of poverty. For this reason there should be a clear plan for construction and community extension approach to care about the maintenance of the technology. About 120 families live in Hashitribab area. All the year round they secure their provision by storing food crops in particular sorghum.

2.3 Photos de la Technologie

2.5 Pays/ région/ lieux où la Technologie a été appliquée et qui sont couverts par cette évaluation

2.6 Date de mise en œuvre de la Technologie

Si l'année précise est inconnue, indiquez la date approximative: :

• il y a entre 10-50 ans

2.7 Introduction de la Technologie

Spécifiez comment la Technologie a été introduite: :

• grâce à l'innovation d'exploitants des terres

Commentaires (type de projet, etc.) :

This scheme was built – in 1999 - on the site of a smaller traditional diversion

3.1 Principal(aux) objectif(s) de la Technologie

• améliorer la production
• réduire, prévenir, restaurer les terres dégradées

3.2 Type(s) actuel(s) d'utilisation des terres, là où la Technologie est appliquée

Commentaires:

Major land use problems (compiler’s opinion): Soil vulnerability to erosion due to rainfall irregularity and characterized by drought cycles; in some years rainfall recorded complete absence. Bare and and dried soils are easily affected by erosion agents (wind and water erosion) as these soils are weakly tolerant. Soils in plains are very poor, not renewable and are affected more than soils in seasonable rivers which are renewable with high soil water moisture.
Major land use problems (land users’ perception): Rain fed soils are weak in moisture holding capacity contrast to soils in flush irrigation soils and preferably used for seasonal cultivation by users and producing stable food crops with good productivity besides all underground water for human consumption and livestock through wells at reasonable depths are to be found.
Future (final) land use (after implementation of SLM Technology): Cropland: Ca: Annual cropping

3.3 Informations complémentaires sur l'utilisation des terres

autre (par ex., post-inondation):

• post-flooding

Nombre de période de croissance par an: :

• 1

Précisez:

Longest growing period in days: 90

3.4 Groupe de GDT auquel appartient la Technologie

• mesures en travers de la pente
• dérivation et drainage de l'eau

3.5 Diffusion de la Technologie

Spécifiez la diffusion de la Technologie:

• répartie uniformément sur une zone

Si la Technologie est uniformément répartie sur une zone, indiquez la superficie couverte approximative:

• 1-10 km2

Commentaires:

This covers just one example of water spreading within the State: there are many but their exact extent is not known. The 2.5 km2 covers the area of the spate water diversion structure in the upper/ mid-stream and the zone where the crop is grown closer to the coastal area. The same is practiced throughout the area in the Red Sea State (It is over 100 and crop are approximately range between 20,000 to 30,000 feddans as an average in the State)

3.6 Mesures de GDT constituant la Technologie

3.7 Principaux types de dégradation des terres traités par la Technologie

Commentaires:

Main causes of degradation: crop management (annual, perennial, tree/shrub) (Clearance of land from resdues to mitigate erosion), overgrazing (Stocking at trees and shrubs continue during the flowering stage preventing seeds production.), industrial activities and mining (To manage mining activities.), change in temperature (Reduced rainfall rate and more affection by wind erosion.), change of seasonal rainfall (More unpredictable and uncertain), Heavy / extreme rainfall (intensity/amounts) (affect in water erosin), droughts (affect passively on the vegetation cover and disintegration of rural families.), poverty / wealth (Not able to conserve resources)
Secondary causes of degradation: soil management (Breaking and blanking soil clods, and leveling and furrowing to increase soil roughness specially at wet seasons to reduce water erodability.), deforestation / removal of natural vegetation (incl. forest fires) (excessive use of tree products), over-exploitation of vegetation for domestic use (Rising population and thus more resource requirements. This is typically is round growing population at urban at centres unlike to people in rural areas except at rainy season where they are gathered), urbanisation and infrastructure development (Sequence to absence of infrastructures and related problems of drought increased rural migration to urban areas.), wind storms / dust storms (Erosion of top soil by wind blown.), floods (unless controlled), inputs and infrastructure: (roads, markets, distribution of water points, other, …) (Blocking water flow in some areas), education, access to knowledge and support services (Low environmental awareness and preparedness.)

3.8 Prévention, réduction de la dégradation ou réhabilitation des terres dégradées

Spécifiez l'objectif de la Technologie au regard de la dégradation des terres:

• prévenir la dégradation des terres
• restaurer/ réhabiliter des terres sévèrement dégradées

4.1 Dessin technique de la Technologie

4.2 Spécification/ explications techniques du dessin technique

Drawing shows the diversion dams, reservoir (hafir) and channal
Location: Hshateribab. Sinkat Locality
Date: 1998

Technical knowledge required for field staff / advisors: moderate (Agriculture extension)
Technical knowledge required for land users: low (Raising community technical capacity)
Main technical functions: control of raindrop splash, control of dispersed runoff: retain / trap, control of concentrated runoff: retain / trap, improvement of ground cover, increase of surface roughness, increase of infiltration, increase of groundwater level / recharge of groundwater, water spreading

Dam/ pan/ pond
Width of ditches/pits/dams (m): 9
Height of bunds/banks/others (m): 2.5
Width of bunds/banks/others (m): 6
Length of bunds/banks/others (m): ˃100

Wall/ barrier
Height of bunds/banks/others (m): 2.5
Width of bunds/banks/others (m): 6
Length of bunds/banks/others (m): ˃100

Lateral gradient along the structure: 0.5 - 1%

4.4 Activités de mise en place/ d'établissement

	Activité	Type de mesures	Calendrier
1.	Excavation of foundation trenches.	Structurel	1 week
2.	Backfilling with heavy soil	Structurel	1 day
3.	Establishment diversion structure	Structurel	8 weeks
4.	Stonepitching by hand	Structurel	3 weeks
5.	Construction of spillway	Structurel	2 weeks

4.5 Coûts et intrants nécessaires à la mise en place

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% des coût supporté par les exploitants des terres
Main d'œuvre	labour	ha	1,0	57,0	57,0
Equipements	machine use	ha	1,0	355,0	355,0
Coût total de mise en place de la Technologie					412,0

4.6 Activités d'entretien/ récurrentes

	Activité	Type de mesures	Calendrier/ fréquence
1.	Tillage	Agronomique	before fluding period

4.7 Coûts et intrants nécessaires aux activités d'entretien/ récurrentes (par an)

Commentaires:

For the diversion structure and spillway at time of construction (1999)

4.8 Facteurs les plus importants affectant les coûts

Décrivez les facteurs les plus importants affectant les coûts :

The slope and depth of the wadi/ khor to be diverted

5.1 Climat

5.2 Topographie

5.3 Sols

5.4 Disponibilité et qualité de l'eau

5.6 Caractéristiques des exploitants des terres appliquant la Technologie

Indiquez toute autre caractéristique pertinente des exploitants des terres:

Land users applying the Technology are mainly disadvantaged land users
Population density: < 10 persons/km2
Annual population growth: 2% - 3%
100% of the land users are poor.
Off-farm income specification: Other activities include casual labour and livestock raising

5.7 Superficie moyenne des terres détenues ou louées par les exploitants appliquant la Technologie

5.8 Propriété foncière, droits d’utilisation des terres et de l'eau

Propriété foncière:

• communauté/ village
• individu, avec titre de propriété

Droits d’utilisation des terres:

• communautaire (organisé)
• individuel

5.9 Accès aux services et aux infrastructures

6.1 Impacts sur site que la Technologie a montrés

Impacts socio-économiques

Production

Disponibilité et qualité de l'eau

Revenus et coûts

Impacts socioculturels

Impacts écologiques

Cycle de l'eau/ ruissellement

Sols

Autres impacts écologiques

6.2 Impacts hors site que la Technologie a montrés

6.3 Exposition et sensibilité de la Technologie aux changements progressifs et aux évènements extrêmes/catastrophes liés au climat (telles que perçues par les exploitants des terres)

Changements climatiques progressifs

Changements climatiques progressifs

	Saison	Type de changements/ extrêmes climatiques	Comment la Technologie fait-elle face à cela?
températures annuelles		augmente	bien

Extrêmes climatiques (catastrophes)

Catastrophes hydrologiques

	Comment la Technologie fait-elle face à cela?
inondation générale (rivière)	bien

Commentaires:

Construction of water spreading devices serves to preserve water, reduce the waste, increase soil moisture capacity and raise soil fertility (silt accumulation)

6.4 Analyse coûts-bénéfices

Quels sont les bénéfices comparativement aux coûts de mise en place (du point de vue des exploitants des terres)?

Commentaires:

no maintenance carried out so not applicable here

6.5 Adoption de la Technologie

• plus de 50%

Commentaires:

75% of land user families have adopted the Technology with external material support
102 land user families have adopted the Technology with external material support, scheme construction subsidised by Government
15% of land user families have adopted the Technology without any external material support
18 land user families have adopted the Technology without any external material support
There is no trend towards spontaneous adoption of the Technology. People cannot construct khor/ wadi diversion barriers themselves by hand

6.7 Points forts/ avantages/ possibilités de la Technologie

Points forts/ avantages/ possibilités du point de vue du compilateur ou d'une autre personne ressource clé
Useful and important in the area where floodwater harvesting/ spate irrigation is the only option for crop production. No rain fed irrigation system on the Red Sea State unlike to other Sudan.

6.8 Faiblesses/ inconvénients/ risques de la Technologie et moyens de les surmonter

Faiblesses/ inconvénients/ risques du point de vue de l’exploitant des terres	Comment peuvent-ils être surmontés?
SLM not falls under the community responsibility. They believe SLM is completely Gos role.	Land users awareness and involvement
They don’t think that community plays a role in the ongoing soil and vegetation degradation	Rotational grazing and seed broadcasting
They also say no regular concern by the government is given in relation to land reclamation	A location of budget and equipment to reclaim land and natural vegetation conservation.
They confirm that the physical conditions played a great role in land degradation e.g. drought aridity and high temperatures .	To ensure water harvesting and without waste.

Faiblesses/ inconvénients/ risques du point de vue du compilateur ou d'une autre personne ressource clé	Comment peuvent-ils être surmontés?
High cost (needs machinery to move earth)	More support from Government and outside
Not enough trained personnel	More up-grading skills are required
Very little data available (apart from construction details)	Better system of monitoring and evaluation
Low technical capacity of the community	Capacity building and training

7.1 Méthodes/ sources d'information