Rehabilitation of Small Tank Catchment Areas [Sri Lanka]

  • Creation:
  • Update:
  • Compilador/a:
  • Editor:
  • Reviewer:

Reporting Entity: Sri Lanka

Clarify if the technology described in the template, or a part of it, is covered by property rights: Não

Completeness: 91%

General Information

General Information

Title of best practice:

Rehabilitation of Small Tank Catchment Areas


Sri Lanka

Reporting Entity:

Sri Lanka

Property Rights

Clarify if the technology described in the template, or a part of it, is covered by property rights:



Prevailing land use in the specified location

  • Other (please specify)

Catchment area of the tank feeding the tanks

Contribution to Desertification, land degradation and drought (DLDD) measures

  • Mitigation
  • Rehabilitation

Contribution to the strategic objectives

  • To improve the living conditions of affected populations
  • To improve the conditions of affected ecosystems

Linkages with the other best practice themes

  • Capacity-building and awareness-raising
  • DLDD and SLM monitoring and assessment/research
  • Participation, collaboration and networking


Section 1. Context of the best practice: frame conditions (natural and human environment)

Short description of the best practice

The hydraulic civilization of the ancient Sri Lanka, built many small tanks in the Dry Zone of Sri Lanka to retain water to be used in the dry season for agriculture, domestic  consumption and for the domestic animals. These tanks formed a seperate micro environment.


Anuradhapura District (The Dry Zone District of Anuradhapura comes within the North Central Province in Sri Lanka)

If the location has well defined boundaries, specify its extension in hectares:


Estimated population living in the location:


Brief description of the natural environment within the specified location.

This area is part of the lowest peneplain moving from the coast and altitude is 0-125msl. However, there are undulating parts and isolated mountains within the area.|
Specific Soil Type: Reddish Brown
The temperature falls within the range of 25C-37C and the annual rainfall is less than 1500mm.The rainfall is restricted to 3-4 months and the remaining months experiences dry weather.The hydraulic civilization in these areas built small tank systems to retain water for the dry season.

Prevailing socio-economic conditions of those living in the location and/or nearby

The main sources of income is the income received from agriculture. Agricultural practices include paddy and vegetable crop cultivation. Paddy is grown in lowlands with water from the tank and vegetables are grown in "Chenas" (slash and burn)in highlands.
Land tenure system in these areas has led to land fragmentation, specially paddy fields. The paddy lands have been fragmented to the extent of being economically non-viable. This has become a bottleneck in introducing new agricultural practices.
These areas are predominantly agricultural areas and the average income is far below the per capita GDP, which is US$ 2050 in 2009. Contribution to GDP in these district in the North Central Province is only 2.7% and therefore, these people receive minimum income (less than 100US$ a month)|

On the basis of which criteria and/or indicator(s) (not related to The Strategy) the proposed practice and corresponding technology has been considered as 'best'?

The practice can be considered "best" due to the following.
1). Stakeholder participation ensured 2). Minimum cost 3).Environment friendly 4). It has multiple effects 5). Could be early replicated 6). Generates sense of ownership.

Section 2. Problems addressed (direct and indirect causes) and objectives of the best practice

Main problems addressed by the best practice

1). Further degradation of the catchment area and soil erosion 2). Lowering of the water retention capacity of the tank 3). Deterioration of the environment and associated ecosystem services 4). Water scarecity in the dry season 5).Lowering of farmer income and partly malnutrition
6). Conservation of the micro environment   

Outline specific land degradation problems addressed by the best practice

Soil erosion due to clearing of the catchment area for cultivation and other purposes was the main environmental issue. The soil erosion could be mitigated through the adoption of the strategies given in this document.

Specify the objectives of the best practice

1). To mitigate soil erosion in the catchment area of the tank
2). To restore the catchment area
3). To restore micro-environment of the area
4). To avoid water security

Section 3. Activities

Brief description of main activities, by objective

Tree planting in the catchment area with inadequate spaces and adoption of soil conservation measures
Through the adoption of soil erosion practices, and tree planting, it was expected that water retention capacity will increase and the natural environment retain excessive water and release gradually. |
Adoption of conservation practices and awareness on environmental conservation to farmers
With the interaction of activities referred to above 1 and 2, it was expected to restore the micro-environment in the area. Minimal disturbance to the natural environment was the key "slogan" in this exercise.|

Short description and technical specifications of the technology

The activity comprises a mix of activities;
1). Land use planning 2). Identification of suitable crop species, 3). Adoption of soil conservation measures
4). Obtaining stakeholder support. |
The success of the activity was a result of the adoption of a scientific approach for conservation of the catchment that is using land use planning for optimal utilization of land.

Section 4. Institutions/actors involved (collaboration, participation, role of stakeholders)

Name and address of the institution developing the technology

Ministry of Environment
82, "Sampathpaya"
Rajamalwatta Road

Was the technology developed in partnership?


List the partners:

Partners 1). Land Use Policy Planners
        2). Forest Department
        3). Farmer Organizations    

Specify the framework within which the technology was promoted

  • Local initiative

Was the participation of local stakeholders, including CSOs, fostered in the development of the technology?


List local stakeholders involved:

1).  Farmer Organizations

For the stakeholders listed above, specify their role in the design, introduction, use and maintenance of the technology, if any.

The farmers have indigenous knowledge and it has optimally used in this exercise. They were able to assist in demarcating areas, identification of plant species, adoption of soil conservation measures.There were, the real "implementers" of the activities. |

Was the population living in the location and/or nearby involved in the development of the technology?


By means of what?
  • Participatory approaches


Section 5. Contribution to impact

Describe on-site impacts (the major two impacts by category)

The ecosystem will provide shelter for wild fauna and protect animal biodiversity.
With the ecosystem restoration, agricultural production will be increased, increasing productivity of agricultural lands. At the same time, the ecosystem will be restored and nutrient and energy transfers within the ecosystem will be re-established.  |
The improved micro-environment in the area will provide ecosystem services rapid.  As a result, the tank system will receive continuous supply of water thereby increasing agricultural productivity. |
As described in the text, the catchment area restoration will allow to re-generate the system as it was. The micro-environment will start producing ecosystem services.This is extremely important since, about 8 months remain dry in these areas.|
The increased income will increase the purchasing capacity of framers and will increase Physical Quality of Life (PQL) and reduce Human Poverty Index (HPI) and increase their socio - economic level.
The agricultural production will generate more incomes to the farmers thereby uplifting their standard of living

Describe the major two off-site (i.e. not occurring in the location but in the surrounding areas) impacts

The increase in the water retention capacity of the tank will reduce the threat of floods in the lower parts and/or in the tanks located in the down stream. Sometimes tanks are located as a chain, the upper ones feeding the lower ones.|
The ecosystem will have a "spread effect". Other neighboring villagers will start thinking replicating the experiences.

Impact on biodiversity and climate change

Explain the reasons:

Sri Lanka is one of the biodiversity hotspots in the world. Since many floral species and faunal spp. are endemic to Sri Lanka, there is possibility of these species being destroyed, if the catchment area is disturbed  |

Has a cost-benefit analysis been carried out?

Has a cost-benefit analysis been carried out?


Section 6. Adoption and replicability

Was the technology disseminated/introduced to other locations?

Was the technology disseminated/introduced to other locations?



To serve other districts

Can you identify the three main conditions that led to the success of the presented best practice/technology?

The strong commitment from the government side was another reason for the success. The Ministry officials, forest officers,and Officers of the Land Use Policy Planning Department of the district were highly involved and dedicated for the activity. |
The main reason for the success this initiative is the stakeholder participation. In this context, the farmer organization acted as implementer of the programme.They were able to obtain support of all the framers and their contribution was in the form of labour.
The end- results could be seen in the short run, preferably   with a period of 1-2 years. However, it takes years for this
ecosystem to be restored.  |


In your opinion, the best practice/technology you have proposed can be replicated, although with some level of adaptation, elsewhere?


Section 7. Lessons learned

Related to human resources

1). Stakeholder participation is essential for the success of country based activities. Their involvement should be obtained for planning, implementation and monitoring of projects.2). Top-down approach is unsuccessful in activities where strong country participation is needed
3). Through a well coordinated approach and guidance, we can develop country leaders. |

Related to financial aspects

1). Costs could be minimized with strong stakeholder participation. 2).Impacts of these projects cannot be measured properly on cost- benefit analysis  eg. aesthetic value of a tank system and associated environment and fresh air. 3). However, finance becomes a limiting factor. Therefore, mobilization of resources is necessary  |

Related to technical aspects

1). Adoption of scientific approaches in every activity is essential. In this case, the project became successful since the area was mapped using modern land use planning techniques 2). The technology should be people friendly and people centric. Then the technology is well received by the community 3). Technology should be simple to the extent possible to be understood by the people.

Links and modules

Expand all Collapse all