(2)Covering over drains shall be flush with the top of the retaining walls of the drains provided that the depth of the drain below the coverings is considered sufficient by the Executive Officer to carry the storm flow. A covering slab may be laid on the top of the retaining walls in rate cases.where it may be necessary to do so in order that water-way of the drain may not be restricted or in cases where the Executive Officer has no objection, provided that the previous sanction of the Council obtained and that a suitable concretes ramp is constructed on the street side the raised slab leading from the level of the top of the slab to the street level.
