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

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)

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

2.1 Short description of the Technology

Definition of the Technology:

Local materials and knowledge can be used to construct low-cost structural measures that help to prevent the erosion of riverbanks and the loss of agricultural and residential land.

2.2 Detailed description of the Technology

Description:

Riverbank cutting occurs naturally along the rivers that run along the foothills of the Chure (Siwalik) range in Nepal when the stream collides with the river bank or the bank is eroded by water coming from agricultural land above the affected area. When riverbank cutting occurs, it leaves behind an eroded area shaped like a small cliff. This erosion takes place naturally and is difficult to stop because the site is devoid of natural vegetation. It is important to undertake conservation measures because when the riverbank is eroded it damages agricultural land and decreases soil fertility. When the productivity of the land is decreased it affects the lives and livelihoods of nearby communities most of whom are subsistence farmers.

Purpose of the Technology: Communities have developed local measures to help protect the riverbanks and to prevent further erosion and cutting. This technology uses both structural and vegetative measures to help control the erosion and protect both agricultural land and settlement areas from flooding. Check dams are placed at intervals to divert water, additional support is provided by spurs. Bamboo rhizomes are planted between them and Napier grass (Pennisetum purpureum) is planted at the back of the structures so that as the plants grow their roots help to anchor the structure. The washed out areas can be used to generate some income by planting them with greenery and fruit trees. The site needs to be monitored annually and where necessary the structures either need to be repaired or supplemented by building additional structures.

Establishment / maintenance activities and inputs: This technology is a blend of local skills and expertise with some external technical input. The key features of the technology are as follow:
• It uses locally available construction materials, tools, equipment, and vegetation.
• It is easy to replicate.
• It is affordable for local people.
• It is environmentally friendly.
A demonstration plot was established by the District Soil Conservation Office (DSCO) in Dang, but the technology needs to be replicated in other areas with action research and experience

2.3 Photos of the Technology

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

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• through projects/ external interventions

3.1 Main purpose(s) of the Technology

• reduce, prevent, restore land degradation
• protect a watershed/ downstream areas – in combination with other Technologies
• reduce risk of disasters

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

Cropland

• Annual cropping

Number of growing seasons per year:

• 2

Forest/ woodlands

Products and services:

• Fuelwood
• Grazing/ browsing

Comments:

Major land use problems (compiler’s opinion): The land is degraded by riverbed cutting and nearby villages are threatened by flooding. The amount of land available for agriculture decreases annually giving rise to a food security problem. Entire villages may have to move to avoid being flooded.

Forest products and services: fuelwood, grazing / browsing

Livestock is grazing on crop residues

3.5 SLM group to which the Technology belongs

• surface water management (spring, river, lakes, sea)

3.6 SLM measures comprising the Technology

vegetative measures

• V2: Grasses and perennial herbaceous plants

structural measures

• S5: Dams, pans, ponds

3.7 Main types of land degradation addressed by the Technology

soil erosion by water

• Wr: riverbank erosion

Comments:

Main causes of degradation: floods

3.8 Prevention, reduction, or restoration of land degradation

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

• prevent land degradation
• reduce land degradation

4.1 Technical drawing of the Technology

Technical specifications (related to technical drawing):

A low cost riverbank protection scheme that can be implemented using mostly local materials.

Technical knowledge required for field staff / advisors: low

Technical knowledge required for land users: moderate

Main technical functions: control of dispersed runoff: impede / retard, control of concentrated runoff: impede / retard

Secondary technical functions: improvement of ground cover, stabilisation of soil (eg by tree roots against land slides)

Author:

Bhojdeo Mandal, AK Thaku

4.2 General information regarding the calculation of inputs and costs

Specify how costs and inputs were calculated:

• per Technology area

Specify currency used for cost calculations:

• USD

4.3 Establishment activities

4.4 Costs and inputs needed for establishment

If land user bore less than 100% of costs, indicate who covered the remaining costs:

The gabion boxes, the transportation costs, and some skilled labour by DSCO, Dang; whereas, the costs for the tools, local materials, and all of the unskilled labour were borne by the local community

4.5 Maintenance/ recurrent activities

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

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

The costs for the gabion boxes, the transportation costs, and some skilled labour, were borne by the DSCO, Dang; whereas, the costs for the tools, local materials, and all of the unskilled labour were borne by the local community.
All costs and amounts are rough estimates by the technicians and authors.

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 very low

Soil drainage / infiltration is good

Soil water storage capacity is very low

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: 100-200 persons/km2

Annual population growth: 2% - 3%

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:

• communal (organized)

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Socio-cultural impacts

Ecological impacts

Soil

Climate and disaster risk reduction

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)

Hydrological disasters

Comments:

Previously, the problem was tackled using traditional techniques alone but the results were not wholly satisfactory. After modifying (as discussed below) the structures are more robust and can withstand greater floods.

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)?

6.5 Adoption of the Technology

• > 50%

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

47 households in an area of 10 ha

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

• 0-10%

Comments:

There is a little trend towards spontaneous adoption of the Technology

Comments on adoption trend: A community of 47 households has agreed to use this technology to help prevent soil erosion caused by flooding. The community had started to implement local measures to minimize riverbank cutting but the efforts were not successful. The systematic introduction of well-planned gabion spurs and bamboo check dams constructed using only locally available materials, has been successful. The community is convinced that this technology is beneficial and they will continue to propagate it themselves as needed.

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:

District Forest Office, Dang; Soil Conservation and Watershed Management Measures and Low Cost Techniques; Environment Statistics of Nepal, Annual Report (2065/66)

Available from where? Costs?

Available at DSCO, Dang and DCSWM, Kathmandu