PORT OF SEATTLE 
MEMORANDUM 
COMMISSION AGENDA             Item No.      5e 
ACTION ITEM             Date of Meeting   January 22, 2013 

DATE:    January 15, 2013 
TO:      Tay Yoshitani, Chief Executive Officer 
FROM:    Michael Ehl, Director, Airport Operations 
George England, Program Leader, Aviation Project Management Group 
SUBJECT:  North Expressway Wall 14 Improvements (#C800034) 
Amount of This Request:   $0            Source of Funds:  Airport Development
Fund 
Est. State and Local Taxes:  $0             Est. Jobs Created: 3-4 
Est. Total Project Cost:    $958,000 
ACTION REQUESTED: 
Request Commission authorization to approve the change in project scope to include the North
Expressway Wall 14 Improvements as part of the North Expressway Relocation Phase I project,
and for the Chief Executive Officer to direct staff to prepare design documents, advertise for
bids, and award and execute a major public works construction contract for the North
Expressway Wall 14 Improvements project at Seattle-Tacoma International Airport. 
SYNOPSIS: 
The North Expressway Relocation Phase I project is nearly complete. It has reconfigured the
Airport roadway system to support the continued growth at the Airport and the extension of
Sound Transit's LINK light rail system to the Airport. The S. 160th St. return-to-terminal loop
ramp includes Wall 14, which was constructed in an interim configuration given the needs of the
planned North Expressway Relocation Phase II project. This Phase II project has since been
delayed, and there are now structural stability concerns with the interim configuration of Wall
14. This authorization combines design and construction. The completion of the North
Expressway Wall 14 Improvements project will address those structural stability concerns and
support the future development of the North Expressway Relocation Phase II project.
This scope of work was not included in the 2013  2017 capital budget and plan of finance.
Previous savings from the North Expressway Relocation Phase I project, which were transferred
to the Aeronautical Allowance CIP, will be transferred back to cover the budget increase.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
January 15, 2013 
Page 2 of 6 
BACKGROUND: 
In 2004, the Port of Seattle Commission authorized the design of the S. 160th St. Loop Ramp
project that would provide a new return-to-terminal loop ramp in the vicinity of S. 160th St.
During the next few years, the Commission authorized additional project funding for this project,
and for the North Expressway Relocation Phase I project, as part of the combined effort to
relocate the Airport's roadway system and extend Sound Transit's LINK light rail system to the
Airport. The roadway improvements were completed in 2007-2008, the landscaping and art
elements were completed in 2010-2011, and the project is currently in final close out.
During the design of the roadway improvements, the Airport's 2005 Comprehensive
Development Plan was under development. This plan included a project called the North
Expressway Relocation Phase II, which would have relocated the southbound lanes of the North
Expressway. Since this was planned to occur within five years of the completion of the planned
roadway improvements, one of the retaining walls along the North Expressway, Wall 14 (as
shown in Exhibit A), was designed in a temporary configuration since it would be significantly
modified by the North Expressway Phase II project. Wall 14 was designed using a mechanically
stabilized earth (MSE) system that incorporated a geotextile fabric in lieu of a more durable wall
face. Construction began in 2006 and Wall 14 was completed in 2007. During this same time
period the North Expressway Phase II project was delayed and is now considered a long-term
project. 
Since the completion of Wall 14 in 2007, the geotextile fabric face has been degrading due to
ultraviolet light exposure. As a result, the strength of the fabric continues to degrade and the
structural fill retained by this fabric has begun to fall out, which will lead to the settlement of the
roadway above and the potential rotation of the shoulder barrier structure. Based upon field
investigations conducted by structural engineers in the Port's Engineering Department, there is
concern with the structural stability of the MSE system, and it is recommended that a more
permanent wall solution be implemented within the next year in order to avoid potential safety
issues and significantly more costly repairs. 
The North Expressway Wall 14 Improvements project will construct a new structural face along
Wall 14 that will address the stability concerns and provide a long-term solution until the North
Expressway Phase II project occurs. We intend to proceed with this project using in-house
design services with limited specialty consultant support and procure construction as a major
works construction contract. The inclusion of the North Expressway Wall 14 Improvements as
part of the larger North Expressway Relocation Phase I project represents a material change in
the project scope and requires additional authorization by the Commission. This additional
authorization is included in this request. 
PROJECT JUSTIFICATION: 
Authorization of this request will allow the North Expressway Wall 14 Improvements to be
completed, which will address existing structural stability concerns with Wall 14 and provide a
long-term solution until modified by future projects.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
January 15, 2013 
Page 3 of 6 
Project Objectives: 
Provide a permanent wall surface on Wall 14 to protect the structural stability of the
MSE system. 
Minimize the total cost of the improvements since they will be modified by future
projects. 
PROJECT SCOPE OF WORK AND SCHEDULE: 
Scope of Work: 
The North Expressway Wall 14 Improvements includes the construction of a non-architectural
shotcrete wall surface along the entire face of Wall 14 that will be anchored with soil nails or
screws. Landscape improvements along Air Cargo Rd. will not be included since these will be
provided as part of the prospective Air Cargo Rd. Safety Improvements project (#C102162). 
Schedule: 
Advertise Construction Contract: April 2013 
Begin Construction: July 2013 
Construction Complete: October 2013 
FINANCIAL IMPLICATIONS: 
Over the course of this combined effort, the Commission authorized $110,238,700 in project
funds, which were combined under the North Expressway Relocation Phase I (#C800034)
project, and are summarized in the table below. 
Budget/Authorization Summary:               Capital       Expense    Total Project 
Original Budget                       $111,503,000           $0    $111,503,000 
Previous Budget savings                  -$10,236,000           $0    -$10,236,000 
Current Budget request                     $958,000           $0       $958,000 
Revised Budget                      $102,225,000          $0    $102,225,000 
Previous Authorizations                  $110,238,700           $0    $110,238,700 
Current request for Authorization                    $0           $0           $0 
Total Authorizations, including this request      $110,238,700            $0    $110,238,700 
Remaining budget to be authorized                 $0           $0           $0 
Total Estimated Project Cost               $102,225,000           $0    $102,225,000 
In order to provide better definition of the anticipated costs for the North Expressway Wall 14
Improvements project, these costs are included in the project cost breakdown below.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
January 15, 2013 
Page 4 of 6 
Project Cost Breakdown:                   This Request 
Construction                               $524,000 
Construction Management                    $187,000 
Design                                   $68,000 
Project Management                        $109,000
Permitting                                  $21,000 
State & Local Taxes (estimated)                   $49,000 
Total                                     $958,000 
Budget Status and Source of Funds: 
The North Expressway Relocation Phase I (#C800034) project is included in the 2013-2017
Capital Improvement Program and Plan of Finance as an active or in-progress project. The
remaining cash flows were not sufficient to cover this additional scope, so previous budget
savings for this project, which had been transferred to the allowance CIP, will be transferred
back, resulting in no net change to the Aviation capital budget. This project has been funded by
Passenger Facility Charge revenues, revenue bonds, reimbursements received from Sound
Transit, and the Airport Development Fund. The North Expressway Wall 14 Improvements
project is intended to be funded by the Airport Development Fund. 
Financial Analysis and Summary: 
The North Expressway Relocation Phase I project represented a $0.24 increase to the cost per
enplanement (CPE) in 2008 when the roadway improvements were completed. The analysis
below shows the impact of the North Expressway Wall 14 Improvements as if it were a standalone
project. 
CIP Category             Regional Transportation 
Project Type              Airport Access 
Risk adjusted discount rate     Not relevant to decision 
Key risk factors             Not relevant to decision 
Project cost for analysis        $958,000 
Business Unit (BU)          Roadways 
Effect on business performance  Aviation recovers approximately 46% of the capital
and operating costs of roadway projects from the
airlines. 
IRR/NPV             Not relevant to decision 
CPE Impact             Less than $0.01 in 2014 
Lifecycle Cost and Savings: 
The completion of the North Expressway Wall 14 Improvements project will not impact existing
operating and maintenance costs for the Airport roadway system.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
January 15, 2013 
Page 5 of 6 
STRATEGIC OBJECTIVES: 
This project supports the Port's Century Agenda objective to advance this region as a leading
tourism destination and business gateway by meeting the region's air transportation needs at the
Airport for the next 25 years. Completion of the North Expressway Wall 14 Improvements
project will support the continued operation of the Airport roadway system. 
BUSINESS PLAN OBJECTIVES: 
This project supports the Airport's strategic goal of operating a world-class international airport
by ensuring safe and secure operations, and managing our assets to minimize the long-term total
cost of ownership. Completion of the North Expressway Wall 14 Improvements project 
represents the least costly alternative that ensures the continued operation of the Airport roadway
system. 
TRIPLE BOTTOM LINE SUMMARY: 
This project will increase the long-term ability of the Airport to serve a growing number of
passengers. Long-term vitality of the Airport benefits the regional economy, the local
environment, and nearby communities. 
ALTERNATIVES CONSIDERED AND THEIR IMPLICATIONS: 
Alternative 1) Do not complete the improvements to Wall 14  With continued exposure to
ultra-violet light the geotextile face of Wall 14 will continue to degrade. This will result in the
eventual settlement of the roadway above and the rotation of the shoulder barrier structure, 
which would close the S. 160th St. return-to-terminal ramp to all traffic until it was repaired.
This past summer approximately 4,700 vehicles a day used this ramp. This is not the
recommended alternative. 
Alternative 2) Delay the improvements to Wall 14  The geotextile face of Wall 14 has already
degraded in locations where the structural fill it retains is falling out. Delaying the
improvements to Wall 14 will allow the continued exposure to ultra-violet light and the
degradation of the geotextile face, which would result in the loss of additional structural fill.
This will increase the project costs since additional repair costs would be required beyond the
improvements to the wall face. There is also a risk that if the improvements are delayed too long
the roadway could settle and require the closure of the S. 160th St. return-to-terminal ramp. This
is not the recommended alternative. 
Alternative 3) Complete the improvements to Wall 14  Completing the improvements this
coming year represents the least costly alternative. While the geotextile face has degraded in a
few locations, the completion of the improvements this year will stabilize the wall prior to the
need for any additional repair. This alternative also represents the least risk to the Airport
roadway system. This is the recommended alternative.

COMMISSION AGENDA 
Tay Yoshitani, Chief Executive Officer 
January 15, 2013 
Page 6 of 6 
OTHER DOCUMENTS ASSOCIATED WITH THIS REQUEST: 
Attachment A  Wall 14 Location Map. 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS: 
July 27, 2004: The Commission authorized $4,818,000 for the design, environmental
review, site and hazardous material survey, and early relocation efforts for the S 160th
St Loop Ramp project. 
March 3, 2005: The Commission authorized $12,871,000 for the design, environmental
review, vacation of S 170th St, relocation of existing tenant and operators, and
advertise and award a General Contractor/Construction Manager contract for the North
Expressway Relocation Phase I project. 
March 14, 2006: The Commission authorized an additional $6,000,000 for several early
action items (water tower demolition and Engineering modular relocation, access
revisions for Airport properties, relocation of bus stops, relocation of field offices to
support Port staffing, regulated materials management to support the demolition of the
Radisson Hotel, and supporting utility relocations and connections for the S 160th St
Loop Ramp and North Expressway Relocation Phase I projects. 
April 11, 2006: The Commission authorized an additional $76,126,000 for the
construction, including the relocation of tenants and operators from affected properties,
of the S 160th St Loop Ramp and North Expressway Relocation Phase I projects. This
authorization also included additional contract authority in order to construct
improvements for Sound Transit at their cost.