As road surfaces age, deteriorate, and go through resurfacing cycles, maintaining manholes and keeping them at the proper grade becomes increasingly difficult.
Nearly 20 years ago, the Illinois Department of Transportation approved the use of adjustable riser rings when raising utility and manhole rims to grade after pavement lifts. Formal language describing acceptable riser rings was soon included in Illinois DOT’s continually updated Standard Specifications for Road and Bridge Construction — for example, the April 2016 version says:
“… the adjustment of frames and grates may be accomplished through the use of adjusting rings that fit on top of the frame. These
