Description of practice
Intercepting or cut-off drains aim to control soil moisture in fields by bypassing water flow before it enters the field. Cut-off drains in saline areas can divert and remove surface water that would otherwise recharge groundwater. Surface drains should be stabilized with fencing and vegetation cover.
| Examples of how to use intercepting drains | Further information (see Note below) |
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Gravel curtain drainsGravel is laid in a ditch (often combined with a perforated pipe) to form a curtain drain that acts like a gutter system removing water from a protected area. |
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Seepage interceptor drainsDrains are dug at the bottom of a sloping field to intercept the downhill flow of subsurface water. At these locations water can be pushed to the surface due to the sudden gradient change and differences in soil type. |
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Cut-off drainsA cut-off drainage ditch is dug by hand hoe with a gradient of 15-50% to facilitate water removal from sloping agricultural land without scouring the soil. |
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Anti-salt dikeA retention dike is constructed to avoid the intrusion of saline estuary water into paddy fields during the dry season. The dike is equipped with a sluice that is opened in the wet season so that excess water can flow to the river. |
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Note: Most of the Further information links are to a full description of the example in the WOCAT database. However sometimes the link may be to similar practices or a research paper. Occasionally the link is to a commercial product in which case it should be understood that this does not imply any endorsement of the product by iSQAPER.