COMMISSION 
AGENDA MEMORANDUM                        Item No.          10a 
ACTION ITEM                            Date of Meeting        July 26, 2022 

DATE:     July 15, 2022 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Laurel Dunphy, Director, Airport Operations 
Eileen Francisco, Director, Aviation Project Management 
Clare Gallagher, Director, Capital Project Delivery/External Relations 
SUBJECT:  Flight Corridor Safety Program 2024 
Amount of this request:                 $500,000 
Total estimated project cost:          $9,700,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to (1) advertise and execute a
Flight Corridor Safety Program 2024 professional Service Agreement for technical expertise and
support; (2) complete aerial obstruction data collection, field verification, and obstruction data
analysis to identify obstructions at and around Seattle-Tacoma International Airport (Airport)
for program scope refinement; (3) conduct environmental review, and (4) execute agreements
with public agencies as needed for purposes of obstruction management. The estimated cost of
this program planning, data collection work and environmental review is $500,000. 
EXECUTIVE SUMMARY 
Flight Corridor Safety Program 2024 is intended to identify and, remove existing and anticipated
obstructions consisting of trees around the Airport; replant trees of compatible species, in
appropriate locations; acquire property rights as needed to perform obstruction management
and prevent establishment of future obstructions. This program is on-going, necessary to
ensure the airport’s compliance with Federal Aviation Administration regulations, state laws
regarding prevention of hazards to navigable airspace, and the airport’s operating certificate
requiring airport operators to protect safe flight operations into and out of the airport. 
Successful program completion requires a high level of technical expertise and support in the
following areas: aerial obstruction data collection, flight surfaces analysis and data analysis,
field verification, real estate/properties appraisal and identification, permitting, design and
specifications, and forestry sciences. 


Template revised January 10, 2019.

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Meeting Date: July 26, 2022 
Aerial obstruction data collection will be conducted in 2023. Data analysis and field verification
will follow. The environmental review process (e.g. State Environmental Policy Act [SEPA]) will 
begin once the obstructions are identified. Program staff plans to return to Commission in 2024 
to share the data collection and request authorization for the development of environmental, 
design and contract documents;  advertisement  and execution of  construction contracts;
payment to public agencies for them to perform replanting for certain obstructions removed
from their properties;  and  acquisition of  those property rights reasonably necessary for
obstruction management and preventing future creation or establishment of airport hazards. 
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 150/5300.13B, “Object Clearing”. 
d. Grant Assurance 20, “Hazard Removal and Mitigation” 
e. Grant Assurance 21, “Compatible Land Use” 
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 easements—Eminent domain— 
Encroachments prohibited” 
Diversity in Contracting 
Program staff will coordinate with  the Diversity in Contracting Department to identify
appropriate women- and minority-owned business enterprise (WMBE) aspirational goals during
procurement development for the program specific professional service. 
BACKGROUND 
Flight Corridor Safety Program is a continuous program that, approximately every five years, 
evaluates and mitigates obstructions in the vicinity of the airport. This program commenced in
2014 with a Port-commissioned aerial obstruction analysis to compare tree heights to surfaces
commonly used by the FAA to determine obstructions to navigation. The Port completed a
follow-up aerial obstruction analysis in 2018 to update the number of obstructions. In response
to community feedback, Commission guidance and in consultation with the FAA, the Port used 
revised criteria in 2018 to identify obstructions that had the most direct impacts to safe and
efficient aircraft operations. Once all obstructions were verified by site visits, the removal and
replanting work began in 2020. All removal work was completed in Quarter 1, 2022. Replanting 
work is ongoing. 

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

             COMMISSION AGENDA – Action Item No. _10a___                             Page 3 of 6 
Meeting Date: July 26, 2022 
In total, 978 trees were removed. The majority were on Port property (789) with the remaining
on Washington Department of Transportation (WSDOT)  right-of-way (102),  other public
properties (47) and private properties (40).
On Port property, the Port revegetated all sites where trees were removed with native shrubs
and trees at a four to one ratio.  For other public properties, the Port contributed to each
entity’s tree replanting fund at the ratio specified by the entity. For private properties, the Port
offered to replant onsite or replant on Port property up to a four to one ratio. Approximately
12,148 trees have been or will be planted to compensate for the 978 trees that were removed.
The Port coordinated directly with all public and private property owners on scopes of work
specific to their properties and on permanent easements on the properties where there is
potential that additional trees may require removal in the future. The value of each easement
or property interest was site specific, as determined by an appraiser in accordance with
applicable standards for determining fair market value.
Environmental best management practices are an integral part of the Flight Safety Corridor
Program’s overall design and included avoiding tree removal work during the bird nesting
period, leaving vegetation barriers near building and streets, planting low-growing native
varietals that won’t become future obstructions, removing and controlling invasive species 
onsite and, specific to Port property, planting a tall-growing native forest on off-site Port
property to compensate for the mature native trees that were removed.
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,
community input sessions, information in the Port’s community newsletter, door to door
neighborhood  canvassing,  a  project-specific  online  open  house  and  regular  email
communications to relevant port listservs.
The Flight Corridor Safety Program is an on-going program. Staff expects to conduct obstruction 
surveys approximately every five years to ensure flight safety and to meet federal and state
regulations and requirements.  The next obstruction survey will take place in  2023.  The
structure and design of the work that began in 2014 will serve as the basis for the program 
going forward. 
Scope of Work 
Scope of work for this authorization includes: 
(1) advertisement and execution of a program specific professional Service Agreement for
technical expertise and support; 
(2) aerial obstruction data collection, field verification, and obstruction data analysis to identify
obstructions; 

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

             COMMISSION AGENDA – Action Item No. _10a___                             Page 4 of 6 
Meeting Date: July 26, 2022 
(3) environmental review; 
(4)  execute  agreements  with  public  agencies  as  needed  for  purposes  of  obstruction
management. 
Following the above planning scope, Program staff plans to return to Commission to request
authorization for the design and contract documents in 2024. The full Flight Corridor Safety
Program 2024 scope of work includes removing trees identified as obstructions on Port, other 
public agency, and private properties, and replanting trees in appropriate locations. This scope
also  includes  payment  to  public  agencies  for  them  to  perform  replanting  for  certain 
obstructions removed from their properties,  executing agreements with  private property
owners as needed to perform obstruction management and obtaining easements or similar
property interests as the permanent approach for obstruction management. 
Schedule 
Activity 
Advertisement for professional Service Agreement      2022 Quarter 3 
Aerial obstruction data collection                         2023 Quarter 3 
Commission design and construction authorization      2024 Quarter 3 
Design start                                                2024 Quarter 3 
Construction start                                        2024 Quarter 4 
Construction completion                               2025 Quarter 4 to 2026 Quarter 4 
Cost Breakdown         This Request       Total Project 
Planning                    $500,000           $600,000 
Design                              0         $2,620,000 
Construction                        0          6,480,000 
Total                          $500,000          $9,700,000 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1  –  Do not authorize funds for program planning, data collection work and
environmental review. 
Cost Implications: $0 
Pros: 
(1)   No expenditure required 
Cons: 
(1)    FAA  could  consider  the  Airport  to  be  non-compliant  with  Federal  rules  and
regulations. 
(2)    Does not follow the state laws regarding prevention of airport hazards.
(3)    Does not meet the Airport’s operating certificate requirements for airport operators
to protect safe flight operations into and out of the airport. 

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

             COMMISSION AGENDA – Action Item No. _10a___                             Page 5 of 6 
Meeting Date: July 26, 2022 
(4)    Does not meet the Airport’s strategic goals and objectives, such as improving the
operational efficiency and customer experience at SEA. 
This is not the recommended alternative. 
Alternative 2 – Authorization to complete program planning, data collection work and conduct 
environmental review. 
Cost Implications: $500,000 
Pros: 
(1)   Complies with FAA and State regulations to manage identified obstructions in a timely 
manner. 
(2)    Meet the Airport’s operating certificate requirements for airport operators to protect
safe flight operations into and out of the airport. 
(3)    Meets the Airport’s strategic goals and objectives, such as improving the operational
efficiency and customer experience at SEA. 
(4)   Provides time for public engagement and outreach with the local communities. 
(5)   Provides a manageable program to meet the FAA and state regulations to remove 
identified obstructions. The FAA concurs with this approach. 
Cons: 
(1)   Expenditure in 2022, 2023 and 2024. 
This is the recommended alternative. 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary                   Total 
COST ESTIMATE 
Original estimate                                     $9,700,000 
AUTHORIZATION 
Previous authorizations                                 100,000 
Current request for authorization                       500,000 
Total authorizations, including this request              600,000 
Remaining amount to be authorized               $9,100,000 
Annual Budget Status and Source of Funds 
The expenditures will be included in the division’s annual operating budget. The cost for
removal and replanting on Port property is an operating expense and the expenditures on non-
Port property is categorized as non-operating Public Expense. The 2022 operating budget
includes $60,000. The funding source will be Airport Development Fund (ADF). 

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

             COMMISSION AGENDA – Action Item No. _10a___                             Page 6 of 6 
Meeting Date: July 26, 2022 



Financial Analysis and Summary 
Project cost for analysis              $9,700,000 
Business Unit (BU)                  Airfield Movement Area 
Effect on business performance     NOI after depreciation will increase due to inclusion of
(NOI after depreciation)             capital (and operating) costs in airline rate base 
IRR/NPV (if relevant)                N/A 
CPE Impact                       $.01 in 2022-2023, $.05 in 2024, $.17 in 2025, $.10 in
2026 
ATTACHMENTS TO THIS REQUEST 
(1) Presentation slides 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
April 29, 2022 – The Commission Aviation Committee was briefed on the Flight Corridor
Safety Program Overview; 2019 program accomplishments and status; and upcoming
request for Commission authorization for 2024 program in June 2022. 








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