Manhole Rehabilitation

Manholes plays an important part in waste water collection system since they provide access for pipes, but just like pipe system, concrete structures and manholes deteriorates causing infiltration and inflow which will eventually require repair or rehabilitation. Some of the factors that causes this manhole deterioration are corrosion, hydrogen sulfide, and other harmful chemicals. Before undergoing the whole process, a video camera is use to inspect and survey any problems or structural failures on manholes. Once confirmed, the interior surface of the manhole is thoroughly clean by using high pressure jet this is to ensure that it is free from debris, or any foreign materials. After cleansing coatings are applied depending on the choice of method.e process it is important to check the condition of the manhole to know what method to use. Manhole Grouting is a good option to prevent runoff and groundwater from draining into the manhole. Prior to grouting, the manhole is thoroughly clean, after cleansing, a grout is applied from the inside. The applied grout readily mixes with the surrounding soil, and manhole materials creating a water tight seal. Grouting can be completed with a few hours without interrupting service. Manhole Lining is another technique used when there is a need for structural reinforcement, runoff and groundwater seepage, and protection from corrosive gases. Manholes are only replaced when all options have been exhausted. This is done by completely removing the old manhole and replacing it with a new one.