The problem with getting high-speed broadband connectivity everywhere is that it’s challenging, time-consuming, and expensive. To lay the required fiber optic cables, existing streets must be cut and then deeply dredged so crews can get to the buried utilities and set the new lines. Traffic must be re-routed around the construction, which causes additional problems (and costs), and the work is incredibly damaging to roads.

Well, leave it to the "brainiac" engineers of the world to come up with a solution. It’s called micro-trenching, and this method is gaining popularity with service providers, Telecom companies, and municipalities all over the world. Why? Because micro-trenching is far less expensive to deploy, takes less time, and is less damaging to existing roadways and sidewalks. And, for those of you tracking the topic, yes, micro-trenching is one of the proposed methods in discussion for bringing redundant broadband (or, for some residents, Internet service in the first place) to the county "by way of" or "via" the 299 corridor from Redding.

With conventional trenching, once you cut and backhoe a road to lay the fiber, even after repairs, water and debris can eventually seep into the lower road surfaces and cause pot holes, sink holes, and other problems. But, micro-trenching is just like it sounds. It involves cutting a very small slice, typically, half of an inch wide, into the roadway surface along the demarcated route. The trench is shallow, typically 6 inches deep, and does not penetrate beyond the surface layer of the road (the asphalt), so water can’t penetrate the softer, more vulnerable parts of the roadway. Less depth also means that the cables are closer to the surface, easier to get to if there is a problem, and easier to fix.

Micro-trenching does not require the heavy equipment, exorbitant hours, or extended construction timeframes used in typical trenching projects either. It requires just a large, industrial-strength saw, specially designed to cut road surfaces. Crews can often lay a micro trench near where the asphalt meets the cement curb. This location gives the trench additional stability, and ultimately ensures less wear-and-tear because the trench is not in the direct path of moving vehicles. Once the cut is made, the fiber line is placed into the trench. The trench is then backfilled with asphalt, cement, or a grout-like substance.

Trenching can be done for $20 -$60 per linear foot, including materials, compared to the $75 - $100 per foot for conventional trenching. And, micro-trenching takes just a fraction of the time. Journalist Bill Morrow of the San Antonio Business Journal states, "A build may take as little as two days for micro trenching, but 30 or more days for conventional trenching work. From planning to completion, the build time frame for micro trenching may be 50 to 55 days, whereas the traditional approach can take 160 days, or more."

But, micro-trenching is not fool-proof. Much of the fiber optic cable being manufactured today is not air and water tight. Over time, moisture and muck can find its way into the cables causing the need for repairs. Further, the cables are sometimes accidentally cut by workers performing other construction projects. Or, the lines can be cut by severe damage to a roadway, as in an accident that deeply gouges the driving surface. Lastly, micro-trenching doesn’t work everywhere. In some places, the road surfaces are not deep enough to accommodate the work.

At least one company, LiteAccess Technologies, is marketing a product where the fiber optic cables are blown through water-and-air-tight microducts. This technology requires a slightly larger trench at 12-17mm (.47 -.66 inches) wide, but is still much more economical than conventional trenching projects. These cables suffer far fewer failures because they are air and water tight. And, because they are blown in, end-to-end, there are none of the typical signal loss problems associated with conventional splicing of lines.

In recent years, the biggest challenge with getting broadband access everywhere has been the cost, time, and inconvenience of laying the fiber under existing streets and sidewalks.

However, micro-trenching, a system of making much smaller trenches in streets, is gaining popularity due to its many advantages: lower project costs, less time, and far less damage to roads. Micro-trenching does have a few drawbacks and can’t be used everywhere, but most of the disadvantages are mitigated by the ease, cost-effectiveness, and convenience of the technology. Micro-trenching is one step closer to ubiquitous broadband service for all.

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Liz Casey of ButterFat Writing Services, Inc. (www.butterfatwriting.com) provides robust copy and technical writing for clients who want their written collateral to effectively communicate and make them money. She is a member of the Redwood Technology Consortium.

Web Sites Cited and Referenced

Morrow, Bill. "Micro trenching cuts new path to growth in telecom industry". San Antonio Business Journal. March 2003. http://www.bizjournals.com/sanantonio/stories/2003/03/31/focus5.html

Lite Access Company Web site: http://www.liteaccess.com/index.php?option=com_frontpage&Itemid=18

Waterman, Michael. "Micro-trenching: can it cut the cost of fibre to the home?" December 2008. Network Strategies Web site: http://www.strategies.nzl.com/wpapers/2008019.htm

Copyright 2009, Eureka Times Standard Newspaper. The print version of this article first appeared in the 4/24/09 edition of the Times Standard.