



This is really two questions in one. The first is "What is a lateral?"; and the second is "What is trenchless pipe replacement?".
There are several pipes that run underground down the middle of most streets. These are generally larger diameter (10", 12", 14", etc.) and carry water and natural gas to the buildings / residences along that street and sewage away from those buildings. These pipes are typically referred to as "Mains". The pipe between the Main and the building is referred to as the "Lateral". These pipes acquired this name because they attach to the side of the Main and run in a lateral (sideways) direction relative to the Main.
Although there may only be one pipe, Laterals are frequently referred to as Upper and Lower. The Upper Lateral is the section of pipe that runs from the building to some line of demarcation. For water pipes that line is generally the water meter. For sewer pipes that line is generally the property line. The Upper Lateral, in most cases, is the responsibility of the property owner. The Lower Lateral is that portion of the pipe from the line of demarcation to the Main. This section of the pipe is generally owned and maintained by the utility that is usint that pipe to providing its service.
Trenchless technology includes a number of methods for installing and rehabilitating underground utility systems with minimal surface disruption and destruction. The traditional pipe replacement method of digging of a trench from point A to Point B is, in most cases, no longer necessary. Pipes can be repaired or installed by digging two (2) holes as small as 2' by 3' (for some repairs only one is required) leaving the remainder of your yard, driveway, patio, etc. untouched.
The answer to the original question is: Trenchless lateral replacement is the replacement of a pipe that runs from a Main in a public right-of-way to a building, without digging up the ground in between.
