Trenchless Technology Center
Louisiana Tech University

Water Environment Research Foundation

Rehabilitation of defective sewer laterals restores impaired structural integrity and reduced hydraulic capacity of these pipes, as well as improves the leak-tightness of pipes and connections and hence eliminates or minimizes groundwater infiltration into the sewer system and/or exfiltration of wastewater into the surrounding soil. Rehabilitation also prevents root intrusion through defects into the pipes, which is a serious problem for many agencies.

Sewer laterals can be repaired or replaced either over their entire length or only in selected parts.

A number of trenchless rehabilitation methods have been developed for the purpose of lateral repair—the principal methods in use today being cured-in-place (CIP) relining products, replacement by pipe bursting, chemical grouting, and flood grouting. Robotic repairs are a relatively new method, whereas mechanical repair sleeves for sectional repair of laterals are less frequently used.

The lateral rehabilitation methods shown below are included in our database. Click on the link to see details.
CIP Relining
  CIP, Standard Liners
  CIP, Remotely Inverted Standard Liners
  CIP, T-Liners
  CIP, Short T-Liners
  CIP, Top Hats
Pipe Bursting
  Static Pull
  Pneumatic Bursting
Lateral Chemical Grouting
  Grouting, Mainline Packers
  Grouting, Push Type Packers
Flood Grouting
Robotic Repairs
  Robotic, Pressure Applications
  Robotic, Non-Pressure Applications
Mechanical Repair Sleeves
Robotic, Non-Pressure Applications

The damaged area of the connection to which the resin would be applied is first prepared by grinding to cut the pipe wall thickness to the depth required to expose the virgin material of the pipe.

The resin is applied without pressure onto the pipe wall next. The robots can be equipped either with (1) a spatula tool or (2) a lateral shoe (flexible plastic plate) with inflatable bladder that create a temporary mold during resin cure.

Robotic repair systems can use other repair materials instead of resins (e.g., one system uses a fiber-reinforced dry mortar but that system has never been present on the U.S. market).

CompanyAMERDA Robotics (SAF-r-DIG Utility Surveys, Inc)
Product/System NameKA-TE
Web Site
Product MaterialEpoxy resin
InstallationPlugg and
Product CureAmbient
Lateral, Pipe TypeAny
Lateral Dia, Min4 in.
Lateral Dia, Max6 in.
Lateral Dia, Transition-
Repair in Lateral, Max4 in.
Mainline Dia, Min8 in.
Mainline Dia, Max24 in.
Repair in Mainline-
Bends in Lateral, 90sNA
Offset of Joints, Max< 2 in.
Lateral Protruding, Max> 1/4 in. (how much limit?)
Active Leaks (Heavy)Yes
Lateral CleaningYes (roots, mineral buildup)
Cleanout (1 or more)No
Pit(s) ExcavationNo
Entering Private PropertyNo
Lateral PluggingYes (1 hour)
Mainline PluggingNo
Structural RepairYes
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