What is the Difference Between Contour Bunding and Graded Bunding?

By Ritika Pant|Updated : November 8th, 2022

The primary difference between Contour Bunding and Graded Bunding is that Contour Bunding is built along shape or contour lines. The graded bunds commonly used in India, on the other hand, are similar to the narrow base balconies. Though both are types of land management practice, Contour bunding is a management technique for borderline, slanted, and hilly land where the soil productivity is very low.

Difference between Contour Bunding and Graded Bunding

The major differences between Contour Bunding and Graded Bunding are given in the table below:

Contour Bunding 

Graded Bunding

Low annual rainfall (< 600 mm) 

They are used in areas having annual rain greater than 700 mm.

Suitable for permeable soils such as alluvial, red/laterite brown soil, and shallow and medium black soil.

Good for impenetrable soil. 

It is commonly used on farming land up to 6% slope.

Not appropriate on land slopes less than 2% or on slopes greater than 8%.

Found in Maharashtra, Gujarat, Tamilnadu, Karnataka, and Andhra Pradesh.

Found in hilly areas, like Dehradun.

Contour Bunding vs Graded Bunding

Contour Bundin aids in the capture and retention of rainfall before it becomes runoff. Graded bunding is used to create obstacles across the path in order to retain water flowing through the watershed and thus help control soil erosion.

Contour Bunding entails constructing earthen dams across the slope of the land, as closely as possible following the Contour. The area is divided into strips by a series of bunds, which reduces the velocity of the water runoff.

Graded bunds, graded terraces, or channel balconies are laid along a pre-determined longitudinal incline near the Contour but not precisely along the shape. These terraces act as drainage canals to control and conduct runoff at non-erosive velocity.

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FAQs on Difference between Contour Bunding and Graded Bunding

  • The significant difference between Contour Bunding and Graded Bunding is that Contour bunding reduces the slope length, reducing soil erosion. In contrast, Graded Bunding removes excess water, which is not required by the crop. Both types of bunding create barriers across the path to controlling water running in the watershed, thereby preventing soil erosion.

  • The contour bunds are suggested for areas with low annual rainfall (< 600 mm), agricultural fields with permeable soils, and a land slope of less than 6%. In contrast, graded bunds are used for secure disposal of excess runoff in areas with high precipitation and relatively impermeable soil.

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