Illustrate the “Contour bund” and “Farm pond” with neat sketch.
1 Answer
Answer :
Contour Bund:
1) Contour bunds are effective methods to conserve soil moisture in watershed for long duration.
2) Contour bunds are suitable in low rainfall areas where monsoon run-off can be impounded by
3) constructing bunds on the sloping ground all along the contours of equal elevation.
4) Flowing water is intercepted before attains the erosive velocity by keeping suitable spacing between the bunds.
5) Spacing between two contour bunds depends on the slope, the area and permeability of the soil.
6) If permeability of the soil is less, then spacing of bunds is kept less.
7) Contour bunding is suitable on lands with moderate slopes without involving terracing.
Farm Pond
1) A farm pond is a large hole dug out in the earth. It is square or rectangular in shape.
2) It harvests rain Inlet water and stores it for future use.
3) It has an inlet to regulate the inflow and an outlet to discharge excess water.
4) The farm pond is surrounded by a small bund which prevents erosion, on the banks of the pond.
5) Ideally, the farm pond should be dug in to the ground in a naturally low lying area.
6) Some of the soil that is removed for digging the pond can be used to construct an earthen berm around the pond. Trees can be planted on this earthen berm for stability.
7) Greater depth of the pond and less surface area will also reduce evaporative losses. However, depth of pond shall not be more than 5 m, else the cost of excavation will increase.
8) A small settling at the inlet will help to remove silt and the whole pond can be cleaned more easily.
9) The sides of pond should be sloped for stability.