Two Decades of Trenchless Technology in North America – Lessons Learned

摘要

In the past decade North America has seen an alarming acceleration in the rate of decay ofrntheir underground infrastructure systems. This is hardly surprising when the systems arernconsidered from a utility-life-cycle point-of-view. Just after World War II North Americarnsaw a dramatic growth in both population and economic strength. This growth was met withrnthe installation of extensive water and sewer systems to accommodate the growing demands.rnNow, 50 years later, we are seeing the end of the normal utility life cycle, and the subsequentrndisruption to our essential services. Fully 50% of North America’s water and sewer systemsrnhave severe operational problems. Some of the tools that are being employed to addressrnthese problems are trenchless technology based.rnLike other locations, North America started to embrace modern trenchless technologyrnmethods in the late 1970’s and early 1980’s. The first wave of trenchless methods introducedrnto North America were imported from both Japan (microtunneling) and Europe (cured-inplacernpipe) at roughly the same time. The development of a North American technology,rnmini-horizontal directional drilling (MHDD), a technology child of the petroleum industryrnparalleled the introduction of these two methods.rnWhile the adoption of cured-in-place pipe and MHDD has seen tremendous acceleration inrnthe following decades the use of microtunneling has actually flattened in North America.rnThe trenchless technologies that have proved attractive in Europe and Asia are notrnnecessarily the technologies that have seen large-scale acceptance in North America. Why?rnThe reason for the successful adoption of one technology and not another is equally rooted inrnthe culture and technology of the region. Common law, warranty issues, litigation trends,rnrisk behaviours, economic strategies, technology isolation, and the values placed on humanrnlives are just some of the factors that influence the selection of technologies.rnThis paper will look at some trenchless technology success stories, and some not sornsuccessful stories of North American trenchless technology, and consider some of thernunderlying reasons behind the outcomes.