Description of practice
A trench or infiltration ditch is a deep and narrow ground excavation. Dug along contour lines, trenches and infiltration ditches are used to harvest surface water runoff and trap sediment, limiting soil erosion and often leading to progressive terrace formation.
| Examples of how to use trenches and infiltration ditches | Further information (see Note below) |
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Contour trenches with bundsA 1.5 m wide trench is dug along contour lines with the soil piled in a bund alongside to reduce the velocity of runoff, conserve moisture in situ and increase ground water recharge. It is appropriate for use in light soils. |
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Soil faced deep trench bundsA deep trench is dug along contour lines with the soil piled in a compacted bund on the downslope side to harvest surface water and sediment runoff. |
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Contour tied trenchesTrenches with tied downslope soil bunds are constructed along contour lines to trap surface water runoff and sediment from degraded uplands. |
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Contour tied trenches with uphill bundA contour trench is excavated along contour lines to trap runoff and increase infiltration. The trenches are tied, and the excavated soil piled upslope to speed up terrace formation. |
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Infiltration trenchesA trench with a trapezoidal cross-section is excavated along contour lines to trap runoff and increase infiltration with the aim of improving groundwater recharge and plant growth. |
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Retention ditchesA larger infiltration or retention ditch is constructed to trap runoff and increase infiltration for the benefit of the crops. |
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Infiltration ditches and ponding banksA larger scale construction of contour ditches and ponding banks is made to improve rainwater infiltration, groundwater recharge and enhance plant growth while safely discharging excess water to avoid erosion. |
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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.