Question

give reason surface of highway are made ruff and porous ​

Answer 1

hey you here is your answer

Gravel roads can be designed to be porous but unless properly designed and maintained, porous gravel roads can become compacted and their voids clogged with particles creating a surface as impervious as asphalt or concrete. ... No aggregate or sand is used, so costs are less than those of concrete or asphalt are.

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