Problem: MidCoast Council is a small local government area in New South Wales, Australia, responsible for public infrastructure in its region, including the raising of manholes to grade after new paving. Typically, this has been a slow, labor-intensive process due to the weight, relative fragility and imprecision of concrete rings. This wasn’t an attractive solution for MidCoast when faced with dramatically failing pavement in a heavy-use intersection with lots of bus and large truck traffic — the cracked and subsided roadway exposed 2 inches of manhole rim, creating an obvious safety hazard. They had to act quickly to repair the roadway, using a fast and durable technology that would permanently fix the intersection and expose the public and repair crews to minimal risk.

Solution: The council chose a Cretex PRO-RING supplied by ISC Services to make the repair. The manhole grade adjustment system is based on rings made from high-strength lightweight expanded polypropylene. The rings are precisely-sized, lightweight — 14 pounds rather than 240 pounds for a typical concrete ring — and much more efficient to install, usually saving hours of labor and requiring smaller crews. Like concrete, EPP rings have a 100-year lifecycle and don’t degrade or deform under load.

Result: In one morning, MidCoast excavated and installed a 4-inch finish ring (secured and sealed with M1 adhesive) and placed a new heavy-duty cover and frame on top of the Pro-Ring. After backfilling, compaction, and cold mix, the rehabilitated intersection was immediately opened for use by heavy vehicles. 800-345-3764; www.cretexseals.com