Section 165(9) in West Bengal Municipal (Building) Rules, 2007
(9)(a)An internal road must be so constructed as to have a slope inwards towards the hillside. Such slope must be not less than the gradient of the road;(b)Where required, the inner and outer edges of an internal road must be protected by protective walls of such number and placed in such positions as the Board of Councillors may direct and constructed in accordance with the specifications in this rule.
