Before lateral pipe bursting was introduced, trenchless pipe replacement methods catered almost exclusively to municipal or government projects – HDD for new utilities, guided pneumatic impact moles for bursting large sewer and storm mains, hydraulic rod-pusher and pullers for replacing other sewer and utility lines.

All of these earlier methods and machines shared a common scope of work – each was defined by projects that were large and public. By contrast, the first lateral pullers entered an arena whose jobs were small and private.

In this new private market, there were significant challenges to overcome. One major obstacle was pipe approval. Fused HDPE had been used for years by the gas industry, and was common in the existing pipe bursting establishment. However, for the fledgling lateral bursting industry, HDPE was not a preference; it was a demand. Yet, this pipe material was not listed in building codes regulating sewer replacement on private property, and therefore was not allowed.

Other challenges were mechanical. Laterals commonly include physical turns — 1/8 or 1/16 bends in the line — to accommodate the flow path from building exit point to municipal connection. Sewers can exit a building from various points, which are often in restricted space or covered by surface improvements. City or county connections can be at the property line, in a side or rear easement, or in the public right-of-way, depending on the local regulations that define owner responsibility.

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None of the previously available bursting technologies were designed to deal with multiple bends and relatively small pipe; most laterals are 4 inches in diameter. Cured-in-place pipe (CIPP) liners were not as permanent a solution, and compared to bursting, were neither practical nor cost-effective for most laterals, especially those in serious disrepair.

In California, TRIC Tools Inc introduced the first lateral bursting systems to meet these unique logistical conditions. The company’s solution paired flexible replacement HDPE pipe with flexible steel cable to negotiate the inevitable bends in the existing pipeline. TRIC gained approval of HDPE for home sewers, city-by-city, in the San Francisco Bay Area where the company initiated commercial lateral bursting in the late 1990s. Since then, both the pipe and the process have been added to national and international codebooks.

The company’s first pipe bursting systems were devised using modified post-tensioning rams mounted on a pulley base against a resistance plate, directing the cable and pulling force vertically rather than horizontally. This allowed for a very small footprint, which was invaluable for sewers that were either shallow, obstructed, or in tight places, which are conditions that describe many home sewer laterals. These hydraulic rams were small, light, and high-pressure rated, making them portable enough to carry and position by hand, yet powerful enough to burst most home sewers easily.

Trenchless lateral replacement has since been widely accepted, and has become a specialised utility market segment. TRIC continues to expand its patented technology into other utility markets around the world, applying a philosophy of simple and effective solutions to various project scenarios in the underground construction industry.