HomeMy WebLinkAbout05-SCL Creston-Talbot_Project Narrative and Variance Justification Request
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September 24, 2015
Chip Vincent
Department of Community & Economic Development Administrator
City of Renton
1055 South Grady Way
Renton, WA 98057
SCL Overhead Creston-Talbot Fiber Project
Written Request for Variance from Undergrounding Utility Line
Dear Mr. Vincent,
Seattle City Light (SCL) is proposing to install a 5-mile installation of new overhead all-dielectric self-
supporting (ADSS) fiber optic cable between Creston Nelson and Talbot Hill substations near Renton,
Washington. Approximately 2.5 miles of the new line are within the City of Renton. The proposed ADSS
cable would be installed on existing transmission power line structures within the existing transmission
corridor between the two substations. This new ADSS cable would provide a vital data communication link
for SCL’s current and future needs, along with the needs of neighboring utilities. HDR Engineering, Inc.
(HDR) is providing engineering and permitting services to SCL for this project.
HDR staff attended a Pre-Application Meeting (PRE15-000517) with the City of Renton on July 23, 2015. At
this meeting, we were directed to prepare a written request to the Administrator for a variance from
undergrounding the proposed utility line. The letter serves as our written request, and provides
justification and response to applicable review criteria found in Renton Municipal Code (RMC) 4-6-090G.2.
Detailed Project Description:
The portion of the proposed overhead ADSS alignment that would run through the City of Renton would
begin near the intersection of S 130th Street and 84th Avenue S. The ADSS cable would then travel in a
southeastern direction toward the City View Church parking lot north of the intersection of SW Langston
Road and Hardie Avenue SW. The ADSS cable would then continue southeast across SW Sunset Boulevard
and through the Renton Shopping Center parking lot (address of 365 Renton Center Way SW). The cable
would continue southeast across Rainier Avenue S, S Grady Way, and I-405 (near the Chrysler, Hyundai,
and Mazda dealerships, and Roxy Cinema) before turning due east. The remaining stretch of fiber would
then travel up the hill and end at Talbot Substation. The total length of overhead fiber within Renton City
limits would be approximately 2.5 miles. See the attached map for the proposed alignment of the
overhead ADSS fiber optic cable. Aesthetically, the new cable will be generally in line with SCL’s existing
transmission lines (see attached Plan and Profile for more information).
Site Improvements: The project is being designed to attach the new ADSS cable only to existing steel pole
and steel lattice transmission line structures within SCL’s easement. Therefore, it is anticipated that no
site or access improvements would be necessary and ground disturbance would be minimal.
Construction Methodology: A construction crew will need access to each transmission structure site in
order to attach the ADSS cable and required hardware. Retrofitting the cable to each structure includes
the use of special vehicles, equipment, and trained linemen. The anticipated work area at each structure
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site would be approximately 150 radial feet. Construction crews would need access to structure sites after
the new ADSS cable is installed to finalize installation of hardware and remove stringing equipment. Work
associated with this project will occur within SCL’s easement to the extent possible, but portions of the
project will require work within City rights-of-way.
Project Schedule: Project construction is anticipated to begin in November 2015 and would be completed
in December 2015 (approximately 29 days).
RMC 4-6-090 Utility Lines – Underground Installation
RMC 4-6-090 requires all new electrical or communication facilities to be installed underground unless
exempt or a proposal receives a variance from the requirement. Variance procedures are listed in
subsection RMC 4-6-090 where the Administrator of Community and Economic Development has the
discretion to grant variances. There are three review criteria where underground requirements may be
waived by a variance only if the utility owner, user, or any other affected party can demonstrate an undue
hardship in the placement of facilities underground. Responses to the applicable review criteria found in
RMC 4-6-090G.2 are provided below.
2. Review Criteria: Underground requirements may be waived by a variance only if the utility
owner, user, or any other affected party can demonstrate an undue hardship in the placement
of facilities underground. The criteria to determine if there is an undue hardship are:
a. There is a technological difficulty associated with the particular facility, or the particular real
property involved; or
Applicant’s Response:
The new ADSS fiber optic cable is proposed to be co-located on SCL’s existing transmission line
easement and infrastructure. To install the fiber optic line under ground it would require
directional boring under the existing parking lots, streets and highways in that area. The current
design calls for installing an attachment point to the current structures and stringing the fiber
through the hangers. This method is standard and relatively quick and inexpensive. To bore
would require specialized machines and could cause potential problems with existing
underground known (and unknown) utilities.
b. The cost of undergrounding such a facility which is deemed by the Administrator to outweigh
the general welfare consideration implicit in underground installation; or
Applicant’s Response:
The project area within the City of Renton is highly developed, and contains residential,
commercial, light industrial, and transportation uses. Undergrounding of the new ADSS fiber
optic cable would be prohibitively costly due to this high level of development. The cost to
underground the ADSS vs stringing it overhead is significantly larger. Estimates put it roughly 8 to
11 times more than the construction cost for stringing it overhead. The process to underground
it would entail completing a subsurface utility exploration to locate existing utilities and
obstructions along the route, directional boring of the route, installation of the conduit and fiber,
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repairs of the bore locations and clean up. It is the intent that SCL would do the overhead
stringing in house, whereas the underground option would require a special construction crew
for a significant cost increase.
c. The growth pattern of the area has not been sufficiently established to determine the ultimate
service requirements or major service routes.
Applicant’s Response:
This new ADSS cable would provide a vital data communication link for SCL’s current and future
needs, along with the needs of neighboring utilities. The project area that will be served by this
new cable is already highly developed with various residential, commercial, light industrial, and
transportation uses. The new fiber will add security and redundancy to the SCL transmission line
and provide a pathway to yield traffic for other utilities that could use the fiber for their system.
The addition of fiber optics for utilities has become more important as technology progresses
and is pertinent for maintaining the grid.
Based on this information, SCL is requesting a variance from the Administrator from undergrounding the
proposed utility line, and permission to co-locate the new ADSS fiber cable onto SCL’s existing utility line
infrastructure.
If you need additional information or have any questions on this request, please contact Dirk Frailey, HDR
(dirk.frailey@hdrinc.com, 503.423.3887) or Marissa Gifford, HDR (marissa.gifford@hdrinc.com,
425.450.7112).
Sincerely,
Dirk Frailey
HDR Project Manager