Sewer rehabilitation, is defined as the process of repairing, replacing or upgrading existing sewer pipelines by methods such as pipe relining, curing and sealing. Trenchless technology utilizes methods that do not require open excavtaion to replace or repair pipes and has become a method of choice when it comes to rehabilitating sewer pipelines.
Sewer rehabilitation involves methods such as pipe bursting, mechanical spot repair, grout-in-place pipe, thermoformed pipe, shotcrete, cured-in-place pipe (CIIP) and sliplining which require little or no excavation. Thermoformed pipe and cured-in-place pipe are examples of methods utilized where an existing pipe needs repair. These methods are relatively simple but may cause loss of hydraulic capacity. Other methods of repair are used to repair weak spots and leaks where damage has not compromised the entire pipe.