Sediqi Ali Ahmad
Helvetas Swiss Intercooperation
Helvetas Swiss Intercooperation
Sourakhak Watershed Committee, Kahmard
有助于对技术进行记录/评估的机构名称（如相关）HELVETAS (Swiss Intercooperation)
A traditional underground water tank carved out of rocks to collect rainfall and snow water and reduce evaporation losses.
Kanda is an indigenous technology for collecting rain and snow melt. The technology comprises an underground tank carved out of rock (limestone), channels to convey the runoff into the underground tank or kanda and a rocky catchment from where runoff is collected. Kanda technology is applied in Afghanistan in many places, particularly in areas which experience scarcity of water for human beings, livestock and irrigation.
Purpose of the Technology: Due to high evaporation rates and low precipitation, harvesting runoff in open tanks is not an efficient way of water harvesting. HELVETAS Swiss Intercooperation is implementing community based watershed management projects in Kahmard district of Bamyan province (Afghanistan) since 2008 with financial support from the International Swiss Re Award for sustainable watershed management (2009) and the Swiss Agency for Development and Cooperation (SDC). One of the activities for sustainable watershed management is plantation of fruit and non-fruit trees in the selected watersheds (upland areas) which were used for grazing and extraction of vegetation for domestic use. Due to water scarcity in the upland areas, irrigation of the planted saplings becomes very difficult and water has to be transported on donkey from far locations. To overcome this constraint, Kanda was identified as the most potent technology for harvesting runoff and snow melt.
Establishment / maintenance activities and inputs: For constructing Kandas, Kanda makers from Dara-e Suf district in Samangan province had to employed as there are no experts in Kahmard. Based on feasibility studies, eight kandas have been constructed including 4 kandas in Sourakhak wa-tershed and 4 in Baqa Kushta watershed. The size of each kanda is 6 m length, 6 m in width and 3 m in height. To convey the runoff into the tank, 10-20 m long graded channels were carved out of the rocks. The establishment cost of one Kan-da was approximately US$ 7163. Kanda making requires special skills, especially when it is carved out of rocks. A kanda maker has sound understanding of the area’s geology, and this wisdom is gained through learning by doing and ances-tors.. In Kahmard, 2-3 experts worked for 4-5 months for one Kanda.
Natural / human environment: In 2012, due to sufficient rains, 2 Kandas which did not have leakage problems in Sourakhak watershed got full with runoff water, which was then used for irrigating 6500 saplings seven times during the year. Kahmard district has a semi-arid cli-mate. Some years are dry with rainfall of about 190 mm. Considering this context, it becomes very necessary to tap rainwater, especially in the rainfed uplands, and use it for irrigating saplings or for livestock.
Total area covered by the SLM Technology is 0.005 km2.
Kanda technology is an age old water harvesting traditional technology.
- access to water
Major land use problems (compiler’s opinion): Scarcity of water in the upland makes plantation activities and livestock productivity difficult. Carrying water from far places for irrigating plants is an expensive activity.
Major land use problems (land users’ perception): Degraded upland watershed resulting severe flash flood.
Forest products and services: timber, fuelwood, fruits and nuts, grazing / browsing, nature conservation / protection, protection against natural hazards
Other forest products and services: flash flood
Future (final) land use (after implementation of SLM Technology): Grazing land: Gi: Intensive grazing/ fodder production
Longest growing period in days: 90; Longest growing period from month to month: March-July
- Extensive grazing
Specification of other structural measures: Under ground cistern
Secondary types of degradation addressed: Wt: loss of topsoil / surface erosion
Main causes of degradation: over-exploitation of vegetation for domestic use (Bush collection for fire wood), overgrazing (By sheep and goets), droughts (Natural climate phenomenon), land tenure (Common land without good management), poverty / wealth, governance / institutional (Lack of organizationals for organization for supporting management of common resources.)
Secondary causes of degradation: crop management (annual, perennial, tree/shrub) (Rainfed agriculture), Heavy / extreme rainfall (intensity/amounts) (Change in climate patterns), population pressure (Fast increasing population which depands on natural resources for livelihoods), war and conflicts (Leading to uncontrolled cutting down of trees and shrubes)
Technical drawing of a Kanda constructed at Baqa Kushta watershed in Kahmard district (Bamyan province).
Size of one Kanda tank:
108 cu.m water can be stored in one Kanda.
Location: Baqa Koshta watershed. Kahmard
Technical knowledge required for field staff / advisors: high
Technical knowledge required for land users: high
Main technical functions: control of concentrated runoff: retain / trap, water harvesting / increase water supply, Reduction in evaporation and seepage losses
Secondary technical functions: improvement of ground cover
Structural measure: cistern(from rock)
Depth of ditches/pits/dams (m): 3
Width of ditches/pits/dams (m): 6
Length of ditches/pits/dams (m): 6
Construction material (other): Constructed from rock
Helvetas Swiss Intercooperatio, Kabul Afghanistan
Duration of establishment phase: 0 month(s)
|1.||Cleaning of the canals and Kanda||once/year|
|劳动力||Cleaning of the canals and Kanda||persons/day/kanda||2.0||5.0||10.0||100.0|
The kanda is for water collection which runoff and snow melt. The usage of water for sapling irrigation because there is upland and no water resources.
- < 250毫米
- > 4,000毫米
Thermal climate class: temperate
- 0-100 m a.s.l.
- 101-500 m a.s.l.
- 501-1,000 m a.s.l.
- 1,001-1,500 m a.s.l.
- 1,501-2,000 m a.s.l.
- 2,001-2,500 m a.s.l.
- 2,501-3,000 m a.s.l.
- 3,001-4,000 m a.s.l.
- > 4,000 m a.s.l.
- 非常深（> 120厘米）
Soil depth on average: Because there is fully of rocks.
Soil texture: Mostly rocky
Topsoil organic matter: Because there is erosion
Soil fertility is low (Loss by wind and water erosion)
Soil drainage / infiltration is poor because there is fully of rock
Soil water storage capacity because of rocky catchment
Difference in the involvement of women and men: Because there is to much workload
Population density: 10-50 persons/km2
Annual population growth: 2% - 3%
10% of the land users are rich.
40% of the land users are average wealthy.
50% of the land users are poor.
- < 0.5 公顷
- 0.5-1 公顷
- 1-2 公顷
- > 10,000公顷
expense for construction
livelihood and human well-being
Increased availability of water for small scale irrigation such as trees, sapling and livestock and increase successful afforestation in dry land areas which in the longer term will lead to increased income, fuel wood and timber for land user and greener watersheds
aesthetic value due to greener watershed
due to water harvesting
sediments due to excavation of rocks
Contributes to flash flood risk reduction by supporting regreening effort
This technology is very positive and useful for land users and collected the water for irrigation and livestock.
Comments on acceptance with external material support: It is an indigenous technology applied in many other districts of Afghanistan in Dara-e Suf and Ruy-i Doab districts of Samangan province by several families either collectively or privately without external support. In Dare-e Suf are not constructed inside of rocks but in soil.
The technology supports plantation activities in sites which are far from perennial water sources
How can they be sustained / enhanced? The collected water should be used efficiently during irrigation by combining with conservation measures like mulching, drip or pitcher irrigation
As the kanda catchment is rocky, infiltration losses are minimized and most of the surface runoff is harvested
How can they be sustained / enhanced? The channel must be constructed properly so that all runoff is trapped and conveyed to the Kanda.
An indigenous multipurpose technology
How can they be sustained / enhanced? Kanda size can be improved if the catchment area and precipitation amount are considered. This also depends on availability of long-term rainfall data.
Requires minimum maintenance when constructed properly
How can they be sustained / enhanced? Kanda, conveyance canals, sediment pits and catchment areas should be cleaned. If any leakages occur in the tank, they should be sealed.
|Due to a lack of geological and hydro-meteorological information, it is not possible to prepare precise and cost-effective kanda proposals||Make best use of traditional wisdom, install hydro-met stations if possible and make adjustments based on regular monitoring.|
|If the kanda and sediment trap tanks are not cleaned regularly and the kanda opening is not covered, sedimentation can be problem leading to reduced Kanda capacity and also animals could fall||Cleaning and maintenance works must be carried out by the local people every year before spring rains. The openings must be covered.|
|Due to availability of water, there can be grazing pressure near the Kanda||Watershed committee members and guards should ensure that the site is protected from over grazing. Construct Kandas outside the selected watershed for livestock purposes.|
|Establishment cost is high if the catchment is rocky||Needs external support during the establishment phase|
|Lack of kanda makers in some districts like Kahmard||Get kanda makers from other districts and build capacities of interested local people.|
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