When a drain rods and the mechanical rodding may not be able to reach and to clear the blocked manhole Holloway, then it is time to try out the high pressure water jetting. When there is the limited access in the system or in multiple bends that have to be negotiated, the drain jetting can be an answer. Drain jetting is not the tool to clear the blocked drainage only but it can be used in maintaining the sewer system and to remove the debris or the still. It is important for the tree root cutting drain and for discaling the pipe work that was constructed using the materials like the cast iron. The jetters are found in different sizes and shapes using small power washers that the user has in the garage, others are trailer jetter, large volume tanker and van packs that can be used for municipal or industrial sewer system. There is also high pressure water jetter with the hot water jetting units with the jetters that had been adapted for the sand blasting operation. As the time passes and the manholes get increasing in need of the repair, the manhole rehabilitation had become the commonplace. Large city may have to work on many manholes in a year. It is less expansive to unblock the blocked manhole Holloway, instead of replacing and excavating them and it may be expected that the manhole rehabilitation may continue to grow in the segment and in the trenchless sector. To be able to make the highest quality of the manhole rehabilitation, a designing engineer has to combine the knowledge of a manhole conditions and it will be available for the technology and the materials. Engineer has to know which condition of a manhole in order to guide the entire unblocking program. The blocked manhole Holloway has to match with the current manhole conditions or else it may fail.