By the time a manhole is corroded enough that you can see the damage, the utility already has a decision to make: patch it, coat it, line it, or replace it. That decision - and the odor control infrastructure that prevents the next manhole from getting to that point - is where system optimization work happens. This guide covers the standard rehabilitation methods and odor control system components a Class 3 operator needs to evaluate and help specify.
Manhole Rehabilitation Methods
Rehabilitation methods generally fall into two purposes that are easy to confuse: structural renewal (rebuilding load-bearing capacity and shape) and corrosion protection (sealing the surface against further chemical attack). A badly deteriorated manhole often needs both, applied in sequence.
Cementitious liners. Fast-setting, high-strength corrosion-resistant mortars, applied by low-pressure