Astandard burnt clay brick is 10 inches x 5 inches x 3 inches. Thus, one brick requires 150 cubic inch, or 0.0024 cubic metres, of top soil.

A manufacturing unit produces, on average, nearly 20 thousand bricks per day (mean of 10,000 and 30,000). If such a unit functions for six months in a year, it will produce 3.6 million bricks. For this, the unit will remove 3.6 million x 0.0024 cubic metres=8,640 cubic metre of topsoil every year (or, 0.5684 hectares of topsoil 5 feet (1.52 metres) deep). [Volume /depth=area, or 8,640/1.52=5,684 square metres (0.5684 hectare)]

Now, if there are 60,000 such units in India they would be making 60,000 x 3.6 million=200 billion bricks per year. This eats up nearly: 0.5684 hectare per unit x 60,000 units = 34,104 hectares of prime agricultural land.

Total agricultural land in India: 187 million hectares in 2000-2001*.