COMMISSION 
AGENDA MEMORANDUM                        Item No.          8a 
ACTION ITEM                            Date of Meeting      January 28, 2020 
DATE:     January 21, 2020 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Laurel Dunphy, Director, Airport Operations 
Wayne Grotheer, Director, Aviation Project Management
Clare Gallagher, Director, Capital Project Delivery/External Relations 
SUBJECT:  Flight Corridor Safety Program 2019  contracts, agreements, and real property
interests 
Amount of this request:               $5,895,000 
Total estimated project cost:           $8,500,000 
ACTION REQUESTED 
Request commission authorization for the Executive Director to (1) use existing job order
contracts for removal of current and future flight path obstructions from non-port properties
and associated replanting of replacement trees; (2) advertise and execute construction
contracts for replanting of replacement trees; (3) pay fees to the Washington State Department
of Transportation (WSDOT) and local jurisdictions for them to perform replanting for certain
obstructions removed from their properties; ( 4) execute agreements with public agency and
private property owners as needed for purposes of obstruction management; and (5) acquire
those property rights reasonably necessary for obstruction management and preventing future
creation or establishment of airport hazards. The total cost estimate for this request is
$5,895,000 for a total estimated project cost of $8,500,000. 
EXECUTIVE SUMMARY 
This request for authorization supports the port's Flight Corridor Safety Program 2019. The
program is intended to remove current and future obstructions consisting of different species
of trees around Seattle-Tacoma International Airport, replant trees of compatible species in
appropriate locations and acquire property rights to perform obstruction management and
prevent establishment of future obstructions.  Obstructions include any objects penetrating
Federal Aviation Administration (FAA)-designated approach and departure surfaces. Removal of
obstructions will ensure the airport's compliance with FAA regulations, state laws regarding
prevention of airport hazards, and the airport's operating certificate requiring airport operators
to protect safe and efficient flight operations into and out of the airport. 


Template revised January 10, 2019.

COMMISSION AGENDA  Action Item No. 8a                                   Page 2 of 9 
Meeting Date: January 28, 2020 
Aerial obstruction analysis (Light Detection and Ranging, or LiDAR) conducted in 2018 identified
174 trees as obstructions. The 174 trees are located on properties owned by the Port of Seattle,
other public agencies (WSDOT, Highline School District, and City of SeaTac), and private
properties (Hillgrove Cemetery and residentially and commercially zoned properties in the cities
of Burien, Des Moines, and SeaTac).  The 174 trees are a significant reduction from the
approximately 1,600 trees that were originally planned to be removed. The intent is to remove
trees having the highest potential impact to flight operations prior to March 1, 2020, and
complete removal of the remaining trees by December 2020. The port may also remove future
obstructions on properties where obstructions currently exist should the property owner desire
this to occur. This will complete the first cycle of a program to manage obstructions every five
years.  Various approaches have been considered for tree replanting, which may include
partnering with other public agencies. Replanting will occur starting in 2021 on properties
where trees have been removed and, to the maximum extent practicable, on sites near the
airport, without creating future obstructions to the flight paths. To date, the Port has replanted
over four-times the number of trees removed and replaced the existing invasive herbaceous
cover with a dense woody native shrub understory. 
In implementing the Flight Corridor Safety Program 2019, the port will need to memorialize or
assert its rights to access non-port properties for purposes of tree removal and replanting, and
should seek, in coordination with property owners, permanent easements or other lawful
airport protection privileges for continued, long-term protection of the flight surfaces.  For
example,  acquiring  an  easement  from  property  owners  will  protect  against  future
encroachments by establishing appropriate height limitations for any trees or other objects
located on the property, and the easement would provide a clear mechanism for the port to
promptly and efficiently address any future obstructions, such as granting the right to access
the property to address an obstruction, upon reasonable notice to the property owner.
JUSTIFICATION 
There are several federal and state regulations and requirements that provide justification for
obstruction removal. These regulations and requirements include the following: 
1.   Federal Requirements for Airport Operators to Control Obstructions 
a. Federal Aviation Regulation (FAR) Part 77, "Safe, Efficient Use, and Preservation of
the Navigable Airspace" 
b. FAR Part 139, "Certification of Airports" 
c. Advisory Circular (AC) AC 150/5300.13A change 1, including "Maintenance of
obstacle clearance surfaces" 
d. Grant Assurance 20, "Hazard Removal and Mitigation" 
e. Grant Assurance 21, "Compatible Land Use" 



Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. 8a                                   Page 3 of 9 
Meeting Date: January 28, 2020 
2.   State Requirements for Airport Operators to Control Obstructions 
a. RCW 14.12.020, "Airport hazards contrary to public interest" 
b. RCW 14.08.030, "Acquisition of property and easementsEminent domain
Encroachments prohibited" 
Diversity in Contracting 
For both the job order and construction contracts for replanting, port staff will coordinate with
the Diversity in Contracting Department to identify appropriate women- and minority-owned
business enterprise (WMBE) aspirational goals.
DETAILS 
The port conducted an aerial obstruction analysis in 2014 for the removal of trees on port
property in 2017, for which replanting occurred in 2019. The LiDAR compared tree heights to
surfaces commonly used by the FAA to determine obstructions to navigation. These surfaces
are conservative in their application and resulted in a substantial number of trees identified as
obstructions.  The port completed a new LiDAR study in 2018 to update the number of
obstructions, including those on other public agency and private properties.  In response to
community feedback and commission guidance and in consultation with the FAA, the port used
criteria to identify obstructions that had the most direct impacts to safe and efficient aircraft
operations. 
With the new criteria, data updated in 2019 shows 174 trees currently obstructing primary
flight surfaces or expected to obstruct primary flight surfaces within five years.   This is a
substantial reduction from the nearly 1,600 trees originally estimated for this phase. These 174
trees will be removed from public and private property.  Of the 174 trees, 104 are on WSDOT
property or WSDOT right-of-way, 26 are on Highline School District property, 20 on City of
SeaTac-owned property, and 6 are on port property. Another 18 trees are on private property,
including 6 in Hillgrove Cemetery in SeaTac, and 12 on properties elsewhere in SeaTac, Burien
and Des Moines. For trees on WSDOT property, some of these trees would be removed by
WSDOT for the planned expansion of State Route 509.
The flight corridor safety program is an on-going program. Staff expects to conduct obstruction
surveys approximately every five years to ensure safety of flight and to meet the federal and
state regulations and requirements. 
Environmental Review 
On December 2, 2019, the port initiated a 14-day public comment period for the project under
the State Environmental Policy Act (SEPA). During the comment period, the port requested
comments on a detailed SEPA checklist that provided project details and environmental
information. The  SEPA  checklist included the project's  extensive  Regulatory  Approach
Memorandum and Implementation Plan. Eighteen comments were received during the public
comment period. Comments ranged from requests to not remove trees to questions regarding

Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. 8a                                   Page 4 of 9 
Meeting Date: January 28, 2020 
compensation  and request for additional analysis on impacts to local communities.  On
December 17, 2019, the port issued a Final SEPA Determination of Non-Significance based on
the environmental review and comments received. 
The port developed a  replanting plan to  minimize future obstructions, identify planting
standards set forth by the local jurisdictions where obstructions are located, and consider
various approaches to replanting, which may include partnering with other public agencies.
Replanting will occur on-site where existing vegetation is removed or at nearby off-site
properties.   Best management practices will be implemented to minimize environmental
impacts and avoid the primary bird nesting period (March 1  July 15). 
Although removing tree obstructions will cause a temporary reduction of sequestered carbon,
this reduction will be offset by replanting. To demonstrate, mitigation for the 783 trees
removed on Port property between 2016 and 2018 included replanting 3,684 trees and 10,311
native woody shrubs.  The Port replanted over 4 times the number of trees removed and
replaced the existing invasive herbaceous cover with a dense woody native shrub understory.
Therefore,  a lifecycle net  reduction in carbon emissions is expected from this project.
Replanting for trees removed on other public and private property are subject to concurrence
from the property owners but are intended to be commensurate with the previous action. 
Community Engagement 
To support effective communication and transparency with communities affected by the Flight
Corridor Safety Program 2019, the port developed and implemented a comprehensive outreach
and communication plan. The plan includes targeted communication and collaboration with
the cities of SeaTac, Burien, and Des Moines; Highline Public Schools; WSDOT; and individual
outreach to affected property owners.  The outreach efforts also included  coordination
meetings with public agencies, a presentation in the airport's community newsletter (Airmail),
the development of a project-specific online open house and email communications to relevant
port listservs. All communication efforts were designed to inform residents within the airport
communities about the program, the upcoming work within the three cities and the ability to
offer official public comment. 
Property Access and Easements 
The port may use a variety of methods to ensure the right to access non-port properties for
tree removal and replanting and to acquire permanent easements or similar airport protection
privileges for continued, long-term protection of the flight corridor. In all cases, port staff will
negotiate directly with each landowner to acquire the property interests needed. If immediate
tree removal is required, the port may obtain temporary access rights while permanent rights
are negotiated. The value of each easement or property interest will be site specific, as
determined by an appraiser in accordance with applicable standards for determining fair
market value. The port will recommend that landowners seek the advice of independent legal
counsel. 

Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. 8a                                   Page 5 of 9 
Meeting Date: January 28, 2020 

Contracting 
The port has developed a comprehensive plan to address the removal of obstructions by
utilizing individual work orders under an existing Job Order Contract. To ensure timely removal
of objects obstructing approach and departure surfaces, the first work order will begin as soon
as possible and be completed prior to March 1, 2020. The other work orders are planned to
start after July 15, 2020, to avoid the primary bird nesting period. 
Additional contracts will be executed for replanting. For obstructions on the WSDOT and local
jurisdictions' properties,the port will pay into those agencies' existing vegetation programs
instead of undertaking the replanting. The costs for paying into the agencies' vegetation
programs are comparable and the agencies are better equipped to manage and maintain trees
on their property, under their own programs. The decision will be documented  in the 
agreements for obstruction management with the applicable agencies. For other public agency
and private properties, job order and construction contracts for replanting are planned to be
advertised and executed in 2021. 
Scope of Work 
The 2019 program scope of work includes removing trees identified as obstructions on, public
agency, and private properties, and replanting trees in appropriate locations. This scope also
includes executing agreements with public agency and private property owners as needed to
perform obstruction management and obtaining easements or similar property interests as the
permanent approach for obstruction management. In addition to the cost of removing and
replanting trees, program cost under this authorization will also include the cost of acquiring
easements  or  similar  property  interests  as the  permanent  approach  for  obstruction
management, payment to WSDOT and other public agencies for replanting of trees on their
property, safety and site improvements, and environmental measures and monitoring during
construction. 
Schedule 
Activity 
Commission design authorization               2017 Quarter 1 
Design start                                       2017 Quarter 1 
Commission construction authorization          2020 Quarter 1 
Construction start                                2020 Quarter 1 
Construction completion                        2021 Quarter 3 
Cost Breakdown by Phase                             This Request           Total Project 
Design Phase                                                    $0             $2,605,000 
Construction Phase                                       5,895,000              5,895,000 
Total                                                          $5,895,000              $8,500,000 

Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. 8a                                   Page 6 of 9 
Meeting Date: January 28, 2020 

ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1  Status quo, do not remove obstructions in 2020. 
Cost Implications: $0 
Pros: 
(1)    No expenditure required in 2020 to remove obstructions or replant 
Cons: 
(1)    FAA could deem the airport to be non-compliant with federal regulations, in violation
of the airport's grant assurances, or in violation of the airport's operating certificate.
The FAA's options could include: 
(a) Limiting or eliminating any approach and/or departure procedures
considered unsafe; 
(b) Requiring airfield changes that would shorten the available runway length for
departing and arriving aircraft, adversely affecting runway capacity; 
(c) Limiting or eliminating FAA grant funding until the obstructions are removed,
or even demanding repayment as to existing grants (the airport's eligibility
for future grants could also be affected); or 
(d) Pursuing injunctive relief claims. 
(2)    Airlines may be required to take weight penalties and/or not service certain markets,
as aircraft would have to be lighter to take off over the obstructions. 
(3)    This option does not meet the airport's strategy goals and objectives, such as ensuring
safe and secure operations. Doing nothing increases risk to the safety and property of
airport users and nearby land occupants, and associated liabilities. 
(4)    Deferring the obstruction removal will result in construction cost escalation in some
future year for implementation. 
This is not the recommended alternative. 
Alternative 2  One major works contract for all tree removal and replanting in 2021. 
Cost Implications: $8,300,000 
Pros: 
(1) One contract package for all the project scope items. 
Cons: 
(1)    The obstruction removal will not start until 2021. 
(2)    FAA could deem the airport to be non-compliant with federal regulations, in violation
of the airport's grant assurances, or in violation of the airport's operating certificate
until the obstruction removal occurs, implicating the potential enforcement options
identified in (1)(a)-(d) of Alterative 1, above. 
(3)    Airlines may be required to take weight penalties and/or not service certain markets
until obstructions are removed, as aircraft would have to be lighter to take off over
the obstructions. 

Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. 8a                                   Page 7 of 9 
Meeting Date: January 28, 2020 
(4)    This option does not meet the airport's strategy goals and objectives, such as ensuring
safe and secure operations. Doing nothing until 2021 increases risk to the safety and
property of airport users and nearby land occupants, and associated liabilities. 
(5)    One major works contract does not provide as much flexibility for the port to engage a
WMBE firm. 
This is not the recommended alternative. 
Alternative 3  Use Job Order Contracts for obstruction removal in 2020 and Job Order, Small
Works, and Construction Contracts for replanting in 2021.
Cost Implications: $8,500,000 
Pros: 
(1) Removes the most critical obstructions prior to March 1, 2020, and remaining
obstructions by the end of 2020 
(2) Using a variety of contract types will allow port more opportunities to engage WMBE 
(3) Removal in 2020 minimizes the risks of the cons identified in Alternatives 1 and 2 above,
thereby promoting: 
(a) Compliance with federal requirements as to obstructions to navigable airspace; 
(b) Compliance with the airport's grant assurances and operating certificate; 
(c) Avoidance of the potential adverse consequences identified in Alternative 1 at
(1)(a)-(d), above (e.g., affecting Airport operations by limiting or eliminating
approach/departure procedures or reducing runway capacity, jeopardizing
current and future grant funding, potential FAA legal action);
(4) Avoids impacts to Airlines, such as weight penalties and/or not servicing certain
markets, as aircraft would have to be lighter to take off over the obstructions; 
(5) Meets the airport's strategic goals and objectives, such as ensuring safe and secure
operations; and 
(6) Promotes the public safety, health, and general welfare by eliminating airport hazards
and preventing the future creation or establishment of new airport hazards 
Cons: 
(1) Expenditure in 2020 and 2021. 
(2) Most expensive alternative. 
This is the recommended alternative. 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary               Capital        Expense          Total 
COST ESTIMATE (WP: U00506) 
Original estimate                                          $0      $7,227,000     $7,227,000 
Current change                                           0       1,273,000      1,273,000 
Revised estimate                                          0       8,500,000      8,500,000 

Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. 8a                                   Page 8 of 9 
Meeting Date: January 28, 2020 
AUTHORIZATION 
Previous authorizations                                    0       2,605,000      2,605,000 
Current request for authorization                          0       5,895,000      5,895,000 
Total authorizations, including this request                  0       8,500,000      8,500,000 
Remaining amount to be authorized1                    $0             $0             $0 
Annual Budget Status and Source of Funds 
The Flight Corridor Safety Program costs are expense costs. The 2020 operating budget includes
$543,000 for this program. The project costs will be accounted for as public expense and
included in the airline rate base (Airfield Movement Area) as an amortized cost, recognizing
there is a multi-year benefit. The funding source is the Airport Development Fund. 
Financial Analysis and Summary 
Project cost for analysis              $8,500,000 
Business Unit (BU)                  Airfield Movement Area 
Effect on business performance    NOI after depreciation will decrease in the year of
(NOI after depreciation)             expenditure but increase in subsequent years.
IRR/NPV (if relevant)                N/A 
CPE Impact                        $0.01 in 2020, $.01 in 2021 and less than $.01 in 2022 
ATTACHMENTS TO THIS REQUEST 
(1)    Presentation slides 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
November 14, 2017  The Commission authorized the Executive Director to (1) increase the
project budget for the Flight Corridor Safety Program  Phase 1 by $2,600,000 for a new
total of $5,806,000; (2) execute change order(s) in excess of $300,000 as necessary to
complete the tree removal work and (3) advertise and execute a major works construction
contract to remove obstructions and complete replanting for Flight Corridor Safety Program
Phase 1 at Seattle-Tacoma International Airport. 
July 25, 2017  Commission briefing on Flight Corridor Safety Program Sites P-4 and P-5. The
briefing provided a summary of the public engagement workshop that was held on June 5,
2017 to identify a preferred removal and replanting approach with the community's input. 


1 As noted above, the port will repeat the obstruction identification and removal process approximately
every five years.

Template revised June 27, 2019 (Diversity in Contracting).

COMMISSION AGENDA  Action Item No. 8a                                   Page 9 of 9 
Meeting Date: January 28, 2020 
February  21,  2017   Commission  authorized  the  Chief  Executive  Officer  to  prepare
environmental, design and contract bid documents for the Flight Corridor Safety Program
now-combined Phase 2 and Phase 3 at Seattle-Tacoma International Airport for $2,373,000.
The total estimated project cost is $7,227,000. 
November 22, 2016   Commission authorized (1) to award and execute a major works
construction contract to the lowest responsible bidder, notwithstanding the low bid
exceeding the engineer's estimate by more than 10 percent; (2) change the contract
duration as necessary and include additional scope that may be identified, including
deferral of work on selected sites; (3) increase the project budget by an amount not to
exceed $475,000 for a total new project cost of $3,206,000. 
November 1, 2016  Commission public meeting and briefing on the Flight Corridor Safety
Obstruction Management program. The briefing provided an overview of state and federal
laws/requirements, and staff's recommendation of options to modify the current program.
The public meeting also included an extensive public comment period. 
October 25, 2016  Commission considered authorization to award the irregular bid exceeding
10 percent of the engineer's estimate to the lowest responsible bidder but took no action. 
October 11, 2016  Commission considered authorization to award the irregular bid exceeding
10 percent of the engineer's estimate to the lowest responsible bidder but took no action. 
August 23, 2016  A special announcement to Commission by Aviation Operations Director,
Michael Ehl, in regard to the Port issuing the final environmental Mitigated Determination
of Non-Significance (MDNS) for tree removal and replanting as part of the Flight Corridor
Safety Program in Phase One. 
August 9, 2016  Commission authorized the advertisement and execution of a major works
construction contract in the amount of $1,831,000 for a total project cost of $2,731,000. 
February 9, 2016  Commission authorized to design, advertise and execute a major works
construction contract in the amount of $750,000 for a total estimate project cost of
$900,000. 
November 24, 2015  Commission briefed on the Flight Corridor Safety Obstruction
Management program. The briefing provided an overview of state and federal
laws/requirements, and staff's recommendation of a phased delivery approach to complete
the program. 




Template revised June 27, 2019 (Diversity in Contracting).