Changes

no edit summary
__NOTOC__
[[Image:contour trenches trch icon.png|right]]
[[Image:contour_trench.JPG|thumb|right|300px| Contour trench under construction and measuring contours with hose pipes. Photo: WTC.]]
At its simplest, contour trench construction is an extension of the practice of plowing fields at a right angle to the slope. Contour trenches are ditches dug along a hillside in such a way that they follow a contour and run perpendicular to the flow of water. The soil excavated from the ditch is used to form a berm (a narrow shelf) on the downhill edge of the ditch. The berm can be planted with permanent vegetation (native grasses, legumes) to stabilize the soil and for the roots and foliage in order to trap any sediment that would overflow from the trench in heavy rainfall events.
Akvopedia-spade, akvouser, bureaucrat, emailconfirmed, staff, susana-working-group-1, susana-working-group-10, susana-working-group-11, susana-working-group-12, susana-working-group-2, susana-working-group-3, susana-working-group-4, susana-working-group-5, susana-working-group-6, susana-working-group-7, susana-working-group-8, susana-working-group-9, susana-working-group-susana-member, administrator, widget editor
30,949
edits