CHENNAI: The Greater Chennai Corporation (GCC) has directed its engineers to mandatorily mill existing bituminous road surfaces before relaying roads wherever n. It also directs officials to strictly avoid raising road levels through repeated bituminous relaying and to maintain the approved finished road level.Under the new instructions, engineers must inspect and document the existing pavement condition, road levels, camber, cross-fall, longitudinal profile, drainage and adjoining property levels before relaying.