1.2 Contact details of resource persons and institutions involved in the assessment and documentation of the Technology

Name of project which facilitated the documentation/ evaluation of the Technology (if relevant)

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

1.3 Conditions regarding the use of data documented through WOCAT

The compiler and key resource person(s) accept the conditions regarding the use of data documented through WOCAT:

Yes

1.5 Reference to Questionnaire(s) on SLM Approaches (documented using WOCAT)

Participatory approach [Rwanda]

This approach is a contribution of different stakeholders and land users in the identification and resolution of a particular crop land problems, which implicate at the end different stage of intervention by all stakeholders to resolve the problem.

• Compiler: Desire Kagabo
• 02/09/2013 midnight

2.1 Short description of the Technology

Definition of the Technology:

Lining geomembrane plastic for water harvesting and storage is a rainwater harvesting technique used by land users to collect rain water or runoff from a concave watershed to a common well-structured plastic-lined pond for agricultural, domestic and other use.

2.2 Detailed description of the Technology

Description:

Rainwater harvesting initiatives were introduced in Rwanda in 2007, through a government-supported project on a pilot basis in three districts (Ruhango, Bugesera and Kirehe). By 2011, the technology had expanded at exponential rates such that the demand has exceeded the supply. Now the supply policy has shifted from government to private still there is a shortage of plastic lining. The typical design of each pond is trapezoidal in shape, measuring 10.5 by 9 meters top-width, 6.5 by 5 meters bottom width and 2 meters depth and a total storage volume about 120 m3. The plastic lining is factory–manufactured with standard shape and size to fit these dimensions. The ponds are made with this standard design to enable bulk purchase and supply of geo-membranes, to make use of economies of scale. The cost of the geo-membranes was subsidized by up to 100% by the government until 2010 but now only 20% are provided by the government. When this project was initiated, activities related to soil excavation was done by the government. However, with time the government pulled out and farmers are now covering the total cost of excavation and the government intervenes only for the technical compliance. The government provides technicians to train farmers on the safety and management of ponds. The volume of water harvested and stored in the ponds is on average 90 m3. However, water retention within the ponds over time differs with from farm to farm as affected by usage, evaporation and seepage losses. Treadle pumps are sometimes used to lift water by some of the farmers. Among most households, the water from the pond is used for domestic, livestock and supplemental irrigation, especially of horticultural crops. About 20% of the water is used for seedling and fruit production, 75% for livestock watering and 5% for domestic use. When the excavation of the pond is complete, the beds as well as sides of the pond have to be leveled and prepared for laying the lining plastic. Any rocks, large stones or other projections, which might damage the lining plastic, should be removed from the beds and sides of the excavated ponds.

Purpose of the Technology: Lining geomembrane plastic for water storage is designed to reduce seepage losses in ponds. This water is used by smallholder farmers to cope with the beginning of dry season and enhance crops to reach the maturity stage safely.

Establishment / maintenance activities and inputs: A periodical inspection is required for better life of the pond, thus timely maintenance hold the key of success for longer time. The maintenance includes inspection, repairing damages. Regular investigations are required on the pond sides, bottom, the inlet and the emergency outlet. In addition, the pond should be protected from intrusion of animals by constructing a fence around the pond. It is also important to remove aquatic vegetation, silt and sediment periodically that accumulate on the bottom of the pond.

2.3 Photos of the Technology

2.5 Country/ region/ locations where the Technology has been applied and which are covered by this assessment

Country:

Rwanda

Region/ State/ Province:

Rwanda

Further specification of location:

Kayonza District (East provice)

Specify the spread of the Technology:

• evenly spread over an area

If precise area is not known, indicate approximate area covered:

• < 0.1 km2 (10 ha)

Comments:

The area was estimated.

Map

×

2.6 Date of implementation

If precise year is not known, indicate approximate date:

• less than 10 years ago (recently)

2.7 Introduction of the Technology

• Government

Comments (type of project, etc.):

the technology was initiated in 2008

3.1 Main purpose(s) of the Technology

• access to water

3.2 Current land use type(s) where the Technology is applied

Cropland

• Annual cropping

Annual cropping - Specify crops:

• cereals - maize
• legumes and pulses - beans
• vegetables - other

Specify:

Longest growing period in days: 150; Longest growing period from month to month: September – February; Second longest growing period in days: 120; Second longest growing period from month to month: March – July

Comments:

major cash crop: Vegetables
major food crop: Beans
other: Maize

Major land use problems (compiler’s opinion): There were poor yields of crops caused by elongation of dry season and increase of runoff soil erosion (intensive rain during rainy seasons) at the previous season.

Major land use problems (land users’ perception): Low crop production, soil erosion

Livestock is grazing on crop residues

3.4 Water supply

Water supply for the land on which the Technology is applied:

• mixed rainfed-irrigated

3.5 SLM group to which the Technology belongs

• water harvesting

3.6 SLM measures comprising the Technology

structural measures

• S5: Dams, pans, ponds

3.7 Main types of land degradation addressed by the Technology

soil erosion by water

• Wg: gully erosion/ gullying
• Wo: offsite degradation effects

water degradation

• Ha: aridification

Comments:

Secondary types of degradation addressed: Ha: aridification

Main causes of degradation: deforestation / removal of natural vegetation (incl. forest fires), other natural causes (avalanches, volcanic eruptions, mud flows, highly susceptible natural resources, extreme topography, etc.) specify (Steep slopes in many cases over 60%), population pressure (Rwanda’s natural resource is subject to a high density of population with an average of 400 people per ha)

Secondary causes of degradation: overgrazing, urbanisation and infrastructure development, poverty / wealth (Farmers have low income and have less access to off farm income or remittances), education, access to knowledge and support services (High rate of irriteracy)

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:

• reduce land degradation

4.1 Technical drawing of the Technology

Technical specifications (related to technical drawing):

Surface runoff water storage pond have got a reservoir of 10.5m x 9.5m at top and 6.5m x 5m at bottom and a depth of 2m with side slope of 1:1.5. The capacity of one pond is estimated about 120m3.

Location: Kabarondo. Kayonza/West/Rwanda

Date: 2013

Technical knowledge required for field staff / advisors: high (The technology need skilled engineers)

Technical knowledge required for land users: moderate (It need moderately skilled labor to construct the technology under supervision of engineers.)

Main technical functions: control of concentrated runoff: retain / trap, water harvesting / increase water supply

Secondary technical functions: water spreading

Dam/ pan/ pond
Vertical interval between structures (m): 2
Spacing between structures (m): 20
Depth of ditches/pits/dams (m): 2
Width of ditches/pits/dams (m): 9.5
Length of ditches/pits/dams (m): 10.5

Construction material (earth): the original land is digging

Construction material (stone): stones are used to concrete the pond inlet and outlet

Construction material (concrete): Cements, sand

Construction material (other): fencing wire and waterproof steering(plastic sheet)

Lateral gradient along the structure: 0%

Specification of dams/ pans/ ponds: Capacity 120m3

Catchment area: 6ham2

Beneficial area: valleym2

Slope of dam wall inside: 50%;
Slope of dam wall outside: 50%

Dimensions of spillways: 0.8m x0.6mm

For water harvesting: the ratio between the area where the harvested water is applied and the total area from which water is collected is: 1:0.25

Author:

Kagabo Desire and Ngenzi Guy, RAB, 5016 Kigali

4.2 General information regarding the calculation of inputs and costs

other/ national currency (specify):

Rwandan francs

If relevant, indicate exchange rate from USD to local currency (e.g. 1 USD = 79.9 Brazilian Real): 1 USD =:

640.0

4.3 Establishment activities

4.4 Costs and inputs needed for establishment

Comments:

Duration of establishment phase: 2 month(s)

4.5 Maintenance/ recurrent activities

4.6 Costs and inputs needed for maintenance/ recurrent activities (per year)

Comments:

Machinery/ tools: hoes, meter, clinomrter, ect....

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

The most factors that affects the cost is the construction materials and labor.

5.1 Climate

5.2 Topography

5.3 Soils

If available, attach full soil description or specify the available information, e.g. soil type, soil PH/ acidity, Cation Exchange Capacity, nitrogen, salinity etc.

Soil fertility is medium - high

Soil drainage / infiltration is medium

Soil water storage capacity is very high - high

5.4 Water availability and quality

5.5 Biodiversity

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Population density: 200-500 persons/km2

Annual population growth: 3% - 4%

55% of the land users are average wealthy and own 60% of the land.
45% of the land users are poor and own 40% of the land.

Market orientation of production system: (Begetables)

5.7 Average area of land used by land users applying the Technology

5.8 Land ownership, land use rights, and water use rights

Land ownership:

• individual, titled

Land use rights:

• individual

Water use rights:

• open access (unorganized)
• communal (organized)

5.9 Access to services and infrastructure

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Socio-cultural impacts

Ecological impacts

Water cycle/ runoff

Soil

Biodiversity: vegetation, animals

6.2 Off-site impacts the Technology has shown

6.3 Exposure and sensitivity of the Technology to gradual climate change and climate-related extremes/ disasters (as perceived by land users)

Gradual climate change

Gradual climate change

Climate-related extremes (disasters)

Meteorological disasters

Climatological disasters

Hydrological disasters

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?

Comments:

It require light labor during the maintenance activities

6.5 Adoption of the Technology

• > 50%

If available, quantify (no. of households and/ or area covered):

260 household covering 90 percent of stated area

Of all those who have adopted the Technology, how many did so spontaneously, i.e. without receiving any material incentives/ payments?

• 0-10%

Comments:

250 land user families have adopted the Technology with external material support

10 land user families have adopted the Technology without any external material support

There is a little trend towards spontaneous adoption of the Technology

6.7 Strengths/ advantages/ opportunities of the Technology

6.8 Weaknesses/ disadvantages/ risks of the Technology and ways of overcoming them

7.1 Methods/ sources of information

7.2 References to available publications

Title, author, year, ISBN:

Kagera TAMP project website

Available from where? Costs?

http://www.fao.org/nr/kagera/en/