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
CIP, Standard Liners

Standard liners are shaped as simple tubes. They are typically installed through cleanouts or small pits either in the direction towards the house or the mainline and may extend all the way to the mainline, but do not cover the connection. It may be possible to invert these liners from the house basement as well. Most systems on the market are standard liners.

Standard liners are most suitable when laterals to be rehabilitated are long and deep, and when the excavation of pits that would be required by some other methods is not acceptable. Access to private property is usually needed although not always. The method is not suitable for pipes with severe offset joints, many bends, and badly corroded pipes.

CompanyPerma-Liner Industries, Inc. Insituform Raynolds Inliner Masterliner Inc. MaxLiner EasyLiner
Product/System NameLateral Perma-Liner™ Insituform® Lateral Inserv™ Masterflex
Product Material
InstallationPull-in Inversion or Pull-in Inversion Remote Inversion
Product CureAmbient or Steam Ambient, Hot Water or Steam Ambient, Hot Water or Steam Ambient, Hot Water or Steam
Lateral, Pipe TypeAny Any Any Any
Lateral Dia, Min2 in. 4 in. 4 in. 4 in.
Lateral Dia, Max12 in. 12 in. 6 in. 6 in.
Lateral Dia, TransitionYes Yes Yes Yes
Repair in Lateral, Max200 ft 200 60 ft 50 ft
Mainline Dia, Min- - - - - -
Mainline Dia, Max- - - - - -
Repair in MainlineNone None None None None None
Bends in Lateral, 90sOne 90 Multiple 90s Multiple 90s Multiple 90s
Offset of Joints, Max1 in. < 40 % dia < 5% dia < 25% dia
Lateral Protruding, Max- - - - - -
Active Leaks (Heavy)No No No No No No
Lateral CleaningYes Yes Yes Yes Yes Yes
Cleanout (1 or more)Yes Yes Yes Yes Yes Yes
Pit(s) ExcavationDepends Depends Depends Depends Depends Depends
Entering Private PropertyDepends Depends Depends Depends Depends Depends
Lateral PluggingYes (3 hrs amb cure; 1 hr steam) Yes Yes (3 hrs amb cure; 1 hr steam) Yes (2-6 hrs)
Mainline PluggingNo No No No No No
Structural RepairYes Yes Yes Yes Yes Yes
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