Under Your Feet: Fiber Goes Underground

The continuing deployment of fiber optic cable is newsworthy in industry trade publications and the consumer press. Serious home-internet users want more bandwidth to download, upload and stream online video.

To meet that demand, some service providers offer gigabit speeds, which means direct connection to fiber. By late 2015, a Fiber-to-the-Home (FTTH) Council Americas survey found that more than 12.3 million U.S. homes are connected directly to fiber and that 26 million have been “passed,” meaning they are in locations where fiber is close enough for them to be connected.

Some are describing FTTH deployment as a construction boom, but it’s one in which few electrical contractors (ECs) with communications divisions are involved—project owners for that work are the major carriers or builders of small private networks in areas where the big providers don’t go. Such work is very competitive, and margins are typically low.

However, many ECs are actively involved in deploying fiber. For years, contractors with low-voltage and telecom divisions have completed projects that call for outside construction of aerial and underground fiber deployment to business complexes, government facilities, educational institutions and other organizations.

Contractors doing premise wiring (which includes an increasing amount of fiber) find themselves with turnkey projects that include outside fiber runs. Those contractors have the choice of doing the work themselves or subcontracting.

VEC Inc., Girard, Ohio, often has projects that include long, outside runs of fiber, according to project manager Jim Bluedorn.

“We will turnkey projects to include outside segments of fiber as well as the structured wiring,” he said. “Our civil division has the personnel and equipment for excavation, vibratory plowing and directional drilling. Depending on the project and specific needs, we may self-perform the underground work or subcontract it.”

Recent VEC projects that included extensive fiber were airport and gas pipeline projects.

A metropolitan airport project included 11 fiber runs totaling 80,000 feet. The longest was 20,000 feet, most of it trenched.

“Much of the trenching was in paving adjacent to runways,” Bluedorn said. “A rubber-track rock wheel was used to cut a 6-inch-wide trench. Duct banks were installed and fiber run through the ducts. There were a lot of right-of-way crossings. We potholed with vacuum excavation equipment and went under gas lines by directional drilling.

“Because of the airport location, security was tight, and we had to avoid slowing air traffic, subject to a fine of $10,000 per hour for disrupting air traffic,” Bluedorn said. “All fiber installation that required excavation was self-performed. We subbed the directional drilling.”

On the gas pipeline project, VEC installed 72-strand fiber used for communication between facilities. Cable was placed directly over the pipeline.

“Fiber has a higher upfront cost but does not have a reoccurring cost over the life cycle of the pipeline,” Bluedorn said. “Also, fiber is more reliable than microwave communication.”

The cable route’s total length was 35 miles. Some of the fiber was on segments where new pipe was installed, while others were above existing pipe. Work was broken into 10-mile segments. There was one 30-mile run of new pipe. The excavating trench was subcontracted. VEC laid fiber over the pipe in high-density polyethylene (HDPE) conduit placed on two feet of fill on top of the pipe. The remaining trench was then closed, while ensuring the fill material didn’t contain rocks that would damage cable.

“For segments where pipe already was in place, vibratory plows were used to install conduit above the pipeline,” Bluedorn said. “[The] route of the pipeline went through small towns, cities and rural areas where there were drastic elevation changes. Those conditions were challenging and slowed work, which increased labor costs. To get around, we rented a tracked all-terrain vehicle.

“VEC started with electrical and steadily expanded into other areas. With addition of the civil division, we have become more competitive and can control everything on the project, positioning VEC as a total solutions provider to our clients across all industries and all disciplines, including electric, mechanical, fabrication, civil and low-voltage services,” he said.

O’Connell Electric Co., Victor, N.Y., is a full-service electrical contractor that often has contracts that require installation of underground power and communications cable. Most of the company’s outside underground work is part of a project to install cabling components inside buildings.

“O’Connell has the personnel and equipment to perform any type of underground construction with its own crews, but currently, this work is performed by subcontractors,” said Robert Unger, communications division manager. “In addition, the company has RCDDs [registered communications distribution designers] on staff with the capabilities to design and do engineering and has the workforce and equipment to perform construction. For most work involving underground fiber, design time usually is for assistance to a consultant or project owner, rather than a complete design from the beginning.”

The majority of O’Connell’s outside fiber work is for wind farms and power substations, Unger said. Construction methods depend on the project requirements and soil conditions.

“On wind farms, fiber is installed between turbines, and the amount of fiber installed varies by project from 12–20 miles,” he said. “Most is installed by excavation with directional drilling for road crossings.”

At substations, “fiber goes to camera poles and typically are no more than a couple of hundred feet per camera,” Unger said.

O’Connell uses prequalified subcontractors for underground work.

Rosendin Electric Inc., San Jose, Calif., one of the nation’s largest specialty contractors, is involved in broadband network construction and telecommunications design/build services.

“Most projects today require high-speed networks and transmission over distance,” said Ron Wilson, director of engineering. “Both of these capabilities almost always require fiber optic cabling. As facilities are increasingly interconnected, most projects require fiber. In addition, inside facilities can ride on the same network backbone, so, increasingly, fiber is used.”

Rosendin routinely installs the outside plant, and Wilson said the preference is to place it underground. Rosendin will use open-trench installation whenever possible, but the company uses directional drilling in locations where the pathway cannot be obstructed or the cost to close an area is excessive. Cost and schedule generally drive the decision of which installation method is used.

On occasion, Rosendin uses subcontractors for outside segments.

“The main factors in determining whether we self-
perform or subcontract are availability of internal resources, location of the project, project schedule and owner preferences,” Wilson said.

A recent project for a large tech company required burial of network cable.

“The facility entrances were located internally to the building, and the service provider had existing underground facilities adjacent to the site,” Wilson said. “We extended the fiber service underground to the cross-connect rooms. Once inside, the backbone was extended between service rooms in an overhead cable-tray system using an Innerduct system for system separation and protection.”

As the Internet of Things becomes more ubiquitous, the need for high-speed connections will increase.

“This, along with the sheer amount of data being transmitted, drives the need for faster networks both commercially and residentially and means fiber to the desktop and services to residences,” he said.

Commonwealth Electric and Communications Co. of the Midwest, Lincoln, Neb., provides outside plant network construction for private companies, utilities and government agencies, according to Chris Gall, communications manager, who is based in Omaha, Neb.

“In addition, we have multiple RCDDs as well as a complete electrical engineering department,” Gall said. “We have a department that does installation of underground pathways, and, at times, we subcontract this work depending on size, scope of work or current availability of that workforce.”

The outside plant is installed underground.

“In recent memory, we have not done a new install of overhead cabling for outside plant distribution,” Gall said.

Commonwealth buries cable by trenching, vibratory plowing and horizontal directional drilling.

“The most popular is the directional drilling,” Gall said. “This allows for a faster installation with less disruption to the surrounding areas. The decision is based on location and speed of installation. Metro areas want the install in the least amount of time with the least disruptions to traffic and business.”

Commonwealth also has locations in Iowa and Arizona, providing services in construction specialties of commercial, industrial, institutional, communications, outside lighting, and signals and service work.

Baker Electric Inc. in Des Moines, Iowa, recently completed a yearlong project that included installing 220,000 feet of 1-inch conduit and fiber optic cable for the Iowa Department of Transportation’s intelligent transportation system. The route was from Des Moines to Altoona.

Fiber cable placed in the conduit served video cameras and sensors that are part of the state’s intelligent transportation system (ITS).

“The job involved a lot of high-production directional drilling,” said Joe Henkels, Baker Electric Inc., traffic department. “For that reason, we chose to use a subcontractor, rather than our own equipment. In addition to installing conduit and fiber, we did 240 handholds, camera poles and extensive power wiring.”

Information collected by the ITS is sent to a control center in Ames, Iowa, which monitors traffic flow and speeds and controls message boards with information about construction zones, weather, accident locations and other information.

Baker Electric serves commercial, residential, ITS voice and data, lighting, prefabrication, and complete design/build services. Its traffic, underground and signalization division handles all types of underground construction.

About the Author

Jeff Griffin

Freelance Writer
Jeff Griffin, Oklahoma City, is a construction journalist specializing in the electrical, telecommunications and underground utility construction industries. Contact him at up-front@cox.net .

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