Resolution No. 3821, SEA Land Stewardship Plan Page 1 of 7
1
2
PORT OF SEATTLE 3
RESOLUTION NO. 3821 4
5
A RESOLUTION of the Port of Seattle Commission adopting SEA Tree 6
Replacement Standards for Airport Activities Area and SEA 7
Land Stewardship Plan for Seattle-Tacoma International 8
Airport. 9
10
WHEREAS, the Port of Seattle is a special purpose government with a mission to 11
promote economic opportunities and quality of life in the region by advancing trade, travel, 12
commerce and job creation in an equitable, accountable and environmentally responsible 13
manner; and 14
15
WHEREAS, the Port operates essential transportation infrastructure at Seattle-Tacoma 16
International Airport (SEA), to ensure the efficient movement of people and goods in the 17
region, and must utilize land for development and operations; and 18
19
WHEREAS, the Port is committed to responsible management of its natural resources 20
because trees, forests, and other habitat are incredibly important to the environment and 21
provide tremendous benefits to our neighboring communities and the public; and 22
23
WHEREAS, the Port continues to ensure that all its operations and development 24
activities are in compliance with city, state, and federal development standards; and 25
26
WHEREAS, the Port continually strives to go beyond the minimum regulatory 27
requirements to address environmental justice, improve environmental health, increase 28
climate resilience, and improve habitat for fish and wildlife; and 29
30
WHEREAS, the Port Commission, through Resolution No. 3741, adopted the Interlocal 31
Agreement with the City of SeaTac defining the “Airport Activity Area” inside which Port 32
capital development activities are subject to compliance with the Airport Building Department 33
development standards; and 34
35
WHEREAS, Burien, Des Moines, and SeaTac municipal code all include tree 36
replacement standards for development, while no tree replacement standards are currently in 37
effect for the Airport Activity Area; and 38
39
Item Number: 8j_reso
Meeting Date: April 16, 2024
Resolution No. 3821, SEA Land Stewardship Plan Page 2 of 7
40
WHEREAS, the Port Commission, through Order No. 2023-10, adopted Environmental 41
Land Stewardship Principles and Strategies to guide development of Port environmental land 42
stewardship efforts around trees, forest, and other habitat to further improve the livability, 43
accessibility, and environmental health of the region; and 44
45
WHEREAS, the Environmental Land Stewardship Principles recommend a holistic 46
ecological approach, ensuring development and other land use projects replace the ecological 47
function and community benefits of any cleared trees; and 48
49
WHEREAS, the SEA Tree Replacement Standards for Airport Activity Area and SEA Land 50
Stewardship Plan emphasize healthy and self-sustaining forests in harmony with the 51
Commission values recommended in the Environmental Land Stewardship Principles; and 52
53
WHEREAS, the Land Stewardship Plan is a living, operational document used as a 54
framework to steward trees, forests, and other habitats that will be updated administratively 55
on a periodic basis to reflect new and changing conditions. 56
57
NOW, THEREFORE, BE IT RESOLVED by the Port of Seattle Commission as follows: 58
59
SECTION 1. Port of Seattle Commission adopts the Tree Replacement Standards 60
policy directive, attached as Exhibit A to this resolution in alignment with the Commission Order 61
No. 2023-10: Port-wide Environmental Land Stewardship Principles and Strategies. 62
63
SECTION 2. Port of Seattle Commission adopts the SEA Land Stewardship Plan, 64
attached as Exhibit B to this resolution, in alignment with the Commission Order No. 2023-10: 65
Port-wide Environmental Land Stewardship Principles and Strategies. The Plan will be updated 66
administratively, as needed. 67
68
ADOPTED by the Port of Seattle Commission at a duly noticed public meeting thereof, 69
held this 16 day of April, 2024, and duly authenticated in open session by the signatures of the 70
commissioners voting in favor thereof and the seal of the commission. 71
72
73
74
75
76
77
78
79
80
81
82
Port of Seattle Commission 83
Resolution 3821, SEA Land Stewardship Plan Page 3 of 7
84
EXHIBIT A to Resolution 3821 85
86
SEA Tree Replacement Standards For Airport Activity Area 87
88
SECTION 1. Purpose. 89
90
Port-owned properties are subject to tree replacement standards established by the local 91
jurisdictions in which the properties are located. Certain Port-owned properties within the SEA 92
airport boundary, the “Airport Activity Area” as defined in the 2018 Port-SeaTac Interlocal 93
Agreement, attachment to Resolution 3741, are not subject to City of SeaTac tree replacement 94
standards. 95
96
The purpose of this policy directive is to offer tree replacement standards for the “Airport 97
Activity Area”, that may be impacted by Port operational and development purposes, 98
consistent with the Port-wide Environmental Land Stewardship Principles. 99
100
Tree replacement standards include components for retention of existing trees on the 101
development site and replacing trees permitted to be cleared. The retention requirement 102
recognizes the intensive industrial and commercial land use that typifies Port development. 103
The replacement standard relies on a holistic ecological approach that gives credit for planting 104
trees and for taking actions to improve forest health at off-site locations, including protecting 105
the life of existing high-value trees and restoring areas infested with invasive plants to native 106
vegetation. 107
108
This approach is consistent with the Environmental Land Stewardship Principles, which 109
recommends using holistic ecological methods and practices, as well as the SEA Land 110
Stewardship Plan (Exhibit B), which includes site resource documentation that informs project 111
planning and design, including tree replacement. 112
113
SECTION 2. Definitions 114
115
When used in this policy directive, the following words and phrases shall have the meanings 116
given below unless the context in which they are included clearly indicates otherwise: 117
118
A. Adjacent location. Port-owned property contiguous to and easily and directly accessible 119
from the development footprint. 120
121
B. Airport Activity Area (AAA). The area defined in the 2018 Port-SeaTac Interlocal 122
Agreement, attachment to Resolution No. 3741, as being within Airport Building 123
Department jurisdiction and subject to the tree replacement standards herein. 124
125
C. Forest. An area with predominant tree canopy cover. 126
127
128
129
Resolution 3821, SEA Land Stewardship Plan Page 4 of 7
D. Forest cover. The proportion of tree canopy in a given area. Includes trees in forested 130
areas and tree groves as well as individual trees. 131
132
E. High-value tree. A tree providing significant ecological function due to size, maturity, 133
species, or location in a tree grove. In general, trees greater than 30 inches diameter at 134
breast height (30 inches DBH) are considered high-value due to their size. All regulated 135
native conifers occurring within a tree grove that contains at least three trees greater 136
than 30” DBH are considered to be high-value trees. 137
138
F. Invasive species. Non-native plant species that aggressively colonize areas, threating 139
native plants and habitat as well as infrastructure. Invasive species cause environmental 140
and economic harm. Invasive species prioritized for management are listed on King 141
County’s Noxious Weeds List. 142
143
G. Off-site location. Distant from and not directly associated with a proposed development 144
footprint. 145
146
H. On-site location. Within the development footprint, which includes the building and 147
supporting infrastructure (e.g., parking areas, landscaping; exterior fencing and 148
lighting). 149
150
I. Portwide Environmental Land Stewardship Principles. Refers to Order 2023-10, 151
approved by the Commission on July 11, 2023. 152
153
J. Regulated Tree. A tree that is subject to replacement according to the development 154
standards herein. 155
156
K. Tree. A woody perennial plant with a single stem growing to more than 30 feet at 157
maturity and bearing lateral branches beginning some distance above the ground. 158
159
L. Tree Grove. A group of trees that grow close together, generally without many bushes 160
or other plants underneath, and anchored by at least three high-value trees. 161
162
SECTION 3. Scope and Applicability. 163
164
These standards pertains to the “Airport Activity Area”, as defined in the 2018 Port-SeaTac 165
Interlocal Agreement, attachment to Resolution No. 3741. 166
167
SECTION 4. Responsibilities. 168
169
The Port’s Executive Director, or a delegate, shall ensure the Tree Replacement Standards 170
Policy Directive is implemented and adequately funded, and that the Policy Directive is 171
integrated into capital project plans and key operational decisions in the Airport Activity Area, 172
as defined in the 2018 Port-SeaTac Interlocal Agreement, attachment to Resolution 3741. The 173
Executive Director shall also ensure that outcomes associated with the application of the Tree 174
Replacement Standard Policy Directive are transparently documented and publicly exhibited so 175
Resolution 3821, SEA Land Stewardship Plan Page 5 of 7
that the Port of Seattle Commission can review, in public, how projects are meeting its Tree 176
Replacement Standards. The Executive Director shall also ensure that the program evaluation 177
meets the purpose and timeliness identified in Section 6 of this policy. 178
179
SECTION 5. Policy. 180
181
A. Tree Replacement Standards. 182
183
(1) Regulated Tree. A regulated tree must be replaced according to the 184
standards herein. Regulated trees meet one of the following criteria: 185
186
a. equal to or greater than six inches diameter at breast height (6” DBH); or 187
188
b. any tree planted by design as part of landscaping for existing development. 189
190
(2) Tree Retention. The intensive industrial/commercial land use supporting 191
airport operations provides limited opportunity for retaining existing trees on 192
development sites. Therefore, projects with clearing impacts will not be 193
subject to a minimum retention requirement but shall retain existing trees to 194
the extent practicable. 195
196
(3) Tree Replacement. If a Regulated Tree is to be cleared: 197
198
a. It must be replaced at a 4:1 ratio. 199
200
b. Replacement uses a “stewardship credit” approach for which a replacement 201
credit can be generated the following ways: 202
203
i. Tree Planting. Plant one tree in an on-site or off-site location, or 204
ii. Invasive removal. Remove 200 square feet of invasive vegetation 205
from an off-site location and replanting the area with native 206
understory vegetation, or 207
iii. Tree Protection. Protect the life of one tree using one of the following 208
means: 209
a. Retain one regulated tree within the development footprint 210
through project design and construction methods, or 211
b. Protect the life of one high-value tree in an off-site location from 212
invasive threats (e.g., removing English ivy from the tree trunk 213
and vicinity). 214
215
216
217
Resolution 3821, SEA Land Stewardship Plan Page 6 of 7
B. The tree replacement standards shall be supplemented by specific design criteria, to be 218
applied as part of capital project planning and design. The criteria ensure that tree 219
replacement concepts and designs are consistent with Environmental Land 220
Stewardship Principles, operational requirements, and equity policy. 221
222
(1) Tree replacement requirements are to be evaluated using site inventories for 223
the development site and potential adjacent and off-site planting areas. Site 224
inventories are required to be completed as part of the project planning and 225
design. 226
227
(2) Stewardship credits generated by tree planting shall account for greater than 228
50% of the replacement requirement. 229
230
(3) Tree replacement shall be prioritized and maximized first on-site, then adjacent 231
to the development footprint before utilizing off-site locations. 232
233
(4) For tree replacement that occurs on-site or at adjacent locations, projects shall 234
consider the potential for employee access to tree replacement areas to 235
improve project equity and employee wellness benefits. 236
237
(5) Designed tree replacement shall be consistent with rules for safe aviation, 238
including the Wildlife Hazard Management Plan; Flight Corridor Safety Program 239
vegetation height limits and regulatory requirements; and all applicable 240
environmental laws and regulations. 241
242
SECTION 6. Program Evaluation. 243
244
The Executive Director, or a delegate, shall monitor and evaluate progress towards achieving 245
the policy directive. This monitoring and evaluation shall include but not be limited to the 246
following: 247
248
A. Documentation. In alignment with the Airport Building Department permitting, capital 249
projects are required to inventory and documents all trees in the development 250
footprint and trees that are planned for clearing. Projects that clear trees must create 251
a tree replacement plan documenting how trees will be replaced and complete an 252
accounting worksheet demonstrating tree replacement requirements are achieved. 253
254
A comprehensive database will be developed and maintained documenting the 255
location and extent of all tree clearing impacts and replacement actions (tree 256
planting, tree protection, invasive restoration). 257
258
B. Reporting. Documented tree replacement pursuant to the SEA Tree Replacement 259
Policy Directive will be reported annually in the Environment and Sustainability Center 260
of Expertise’s Key Performance Indicators. Staff will present a summary of Key 261
Resolution 3821, SEA Land Stewardship Plan Page 7 of 7
Performance Indicators annually to the Sustainability, Environment, and Climate 262
Committee. 263
264
265
C. When substantive administrative updates to the SEA Land Stewardship Plan are made, 266
Commissioners will be notified through the Sustainability, Environment, and Climate 267
Committee. 268
