HomeMy WebLinkAboutPlanning 2019-04-11 Item 4 - STAFF REPORT - CRITICAL AREAS CODE UPDATEDepartment ofCo unity Develop ent - ack Pace, Director
FILE NUMBERS:
REQUEST:
LOCATION:
PUBLIC NOTICE:
STAFF:
ATTACHMENTS:
Allan Ekberg, Mayor
STAFF REPORT TO THE PLANNING COMMISSION
FOR THE APRIL 11, 2019 HEARING
L18-0056 Critical Areas Code Update
Review and revise Tukwila's Critical Areas regulations, hold a public
hearing and make a recommendation to the City Council.
City Wide
Notice was published in the Seattle Times and a postcard was mailed to
the owners and tenants of all Tukwila parcels on 3/28/19. Proposed
amendments were posted on the website and an email notification was
sent to the interested parties list on 3/22/19. Information about the
update was included in the citywide Stormwater mailer and the
September eHazelnut newsletter. An open house was held on 10/9/18.
Minnie Dhaliwal, Planning Supervisor
A. Proposed TMC 18.45 Critical Areas Code and TMC 18.70 Non-
conforming regulations pertaining to the critical areas.
B. Edits in underline/strikeout version
BACKGROUND
All cities in Washington are required to adopt critical areas regulations by the Growth
Management Act (GMA) (RCW 36.70A.060). Critical areas, as identified in the GMA include
wetlands, frequently flooded areas, streams, geologically hazardous areas (steep slopes), and
fish and wildlife habitat conservation areas. In addition, cities are to give special consideration
to conservation or protection measures necessary to preserve or enhance anadromous
fisheries.
Cities are required to include the best available science in developing policies and
development regulations to protect the functions and values of critical areas (RCW
36.70A.172). All jurisdictions are required to review, evaluate, and, if necessary, revise their
critical areas ordinances according to an update schedule provided per RCW 36.70A.130.
Tukwila's current sensitive area regulations were adopted eight years ago in 2010. Per GMA
the City must periodically consider best available science (BAS) and update its critical areas
ordinance. Any deviations from BAS recommendations should be identified, assessed, and
explained (WAC 365-195-915). Washington State Department of Ecology oversees critical
area updates and provides direction on BAS.
Tukwila City Hall * 6200 Sou
cente
oulevard • Tukwila, A 98188 • 206-433-1800 • Website: TukwilaWA.gov
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L18-0056 Critical Areas Update PC Staff Report
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Staff had a work session with the Planning Commission on this item on November 8, 2019.
The staff report for the November 8, 2018 meeting is available online. Here is the link to staff
report.
The second work session was held on February 28, 2019 and here is the link to the staff report
DISCUSSION
Based on the direction from the Planning Commission staff has prepared revisions to the
critical areas regulations. See Attachment A and B for the proposed revisions. Summary of the
key revisions is included below:
etlands
1. Designation:
• Reference to State delineation manual removed and replaced with language from
WAC 173-22-035, that states identification of wetlands and delineation of their
boundaries shall be done in accordance with the approved federal wetland
delineation manual and applicable regional supplements.
• Five year time limit on wetland reports/delineations established. Generally, any
delineation done more than five years ago needs to be revisited as wetlands can
change significantly in a five-year period due to changes in hydrology, land uses,
and plant species composition. Additionally, approved jurisdictional
determinations by the Corps expire after five years. Revisiting a wetland
delineation that is five or more years old does not necessarily mean a new
wetland delineation needs to be done. It means it may be necessary to revisit the
site to determine whether the delineation is still accurate or needs to be redone
based on current conditions.
2. Rating:
State rating system referenced, which is the Washington State Wetland Rating System
for Western Washington (Hruby 2014, Ecology publication No. 14-06-029). To avoid the
need for future updates related to rating system versions language added, "or as
revised and approved by Ecology".
3. Buffer Widths: Adopt the standard buffer widths recommended by the Department of
Ecology; but allow alternate buffer if impact minimization measures are taken AND
buffer is replanted
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L18-0056 Critical Areas Update PC Staff Report
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Category
Wetland
buffer
width
(ft),
current
TMC
Wetland buffer width (ft), Ecology 2014, high -intensity land use
impact
Habitat
score
<6
Habitat
score
<6
Habitat
score
6-7
Habitat
score
6-7
Habitat
score 8-
9
Habitat
score 8-9
Standard
Buffer
Alternate
Buffer if
impact
minimization
measures
taken AND
buffer is
replanted
Standard
Buffer
Alternate
Buffer if
impact
minimization
measures
taken AND
buffer is
replanted.
Also, 100
feet
vegetated
corridor
between
wetland and
priority
habitats is
maintained.
Standard
Buffer
Alternate
Buffer if
impact
minimization
measures
taken AND
buffer is
replanted.
Also, 100
feet
vegetated
corridor
between
wetland and
priority
habitats is
maintained.
100
100
75
150
110
300
225
II
100
100
75
150
110
300
225
III
80
80
60
150
110
300
225
IV
50
50
40
50
40
50
40
Impact minimization measures to qualify for alternate buffers include the following:
Disturbance
Required Measures to Minimize Impacts
Lights
•
Direct lights away from wetland
Noise
•
Locate activity that generates noise away from wetland
•
If warranted, enhance existing buffer with native
vegetation plantings adjacent to noise source
•
For activities that generate relatively continuous,
potentially disruptive noise, such as certain heavy
industry or mining, establish an additional 10' heavily
vegetated buffer strip immediately adjacent to the outer
wetland buffer
Toxic runoff
•
Route all new, untreated runoff away from wetland while
ensuring wetland is not dewatered
•
Establish covenants limiting use of pesticides within 150
feet of wetland
•
Apply integrated pest management
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L18-0056 Critical Areas Update PC Staff Report
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Disturbance
Required Measures to Minimize Impacts
Stormwater runoff
•
Retrofit stormwater detention and treatment for roads and
existing adjacent development
•
Prevent channelized flow from lawns that directly enters
the buffer
•
Use Low Intensity Development (LID) techniques where
appropriate (for more information refer to the drainage
ordinance and manual)
Change in
regime
water
•
Infiltrate or treat, detain, and disperse into buffer new
runoff from impervious surfaces and new lawns
Pets and
Disturbance
Human
•
Use privacy fencing OR plant dense vegetation to
delineate buffer edge and to discourage disturbance
using vegetation appropriate for the ecoregion
•
Place wetland and its buffer in a separate tract or protect
with a conservation easement
Dust
•
Use best management practices to control dust
4. Interrupted Buffer: Establishes an administrative waiver process for an interrupted
buffer.
a) Defines what qualifies as interrupting the buffer: a public or private road; buildings;
or parking lots. The criteria for waiver include:
i) The existing legal improvement creates a substantial barrier to the buffer
function;
ii) The interrupted buffer does not provide additional protection of the critical area
from the proposed development; and
iii) The interrupted buffer does not provide significant hydrological, water quality and
wildlife buffer functions relating to the portion of the buffer adjacent to the critical
area.
5. Buffer averaging instead of buffer reduction:
Replaces buffer reduction provision with buffer averaging. The total area of the buffer
after averaging is equal to the area required without averaging and the buffer at its
narrowest point is never less than either 3/4 of the required width or 75 feet for Category I
and II, 50 feet for Category III, and 25 feet for Category IV, whichever is greater.
6. Alterations:
No changes to the exemption level. The existing code provides an exemption for certain
wetlands that are under 1,000 square feet. The exemption is from sequencing (showing
that the impact cannot be avoided or minimized). Mitigation of the impacts is still
required per Ecology. Exempt wetlands have to meet the following criteria:
a) habitat score under five;
b) are not associated with a riparian habitat or Shorelines of the State;
c) are not part of a wetland mosaic, and
d) do not contain priority habitat.
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L18-0056 Critical Areas Update PC Staff Report
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7. Mitigation Standards: Mitigation ratio for buffer impacts is added at 1:1
8. Wetland and buffer mitigation location:
The current code prefers off -site mitigation be located within City of Tukwila's
boundaries. However State and federal agencies advocate use of alternative mitigation
methods such as mitigation banks or in -lieu -fee programs. In order to be consistent with
regulations of these agencies the proposed changes allow for purchase of mitigation
credit from an in -lieu fee program or bank, if that is the best choice ecologically for a
project.
Il. atercourses
Rating and buffer widths:
Ratings nomenclature updated to reflect Washington Department of Fish and Wildlife
ratings for simplicity. Type 1, 2, 3, 4 changed to S (Shoreline), F (Fish bearing), NP
(Non -fish bearing perennial), Ns (Non -fish bearing seasonal). No change in the buffers
of S, F, Ns. The standard buffers of Np could be lowered from 80 feet to 50-65 range
with buffer enhancement.
Stream Type
Wate rcourse
�j►Buffer
(ft), TNIC
S
Regulated under
Shoreline Master
Program
F
100
Np
Standard buffer 80
Alternate buffer in the
range of 50-65 with
buffer enhancement
Ns
50
2. Buffer averaging vs reduction:
Replaces buffer reduction provision with buffer averaging so long as the total area of the
buffer after averaging is equal to the area required without averaging and the buffer at
its narrowest point is never less than 3/4 of the required width.
3. Interrupted buffer: Establishes an administrative waiver process for an interrupted
buffer.
a) Defines what qualifies as interrupting the buffer: a public or private road; buildings;
or parking lots. The criteria for waiver include:
i) The existing legal improvement creates a substantial barrier to the buffer
function;
ii) The interrupted buffer does not provide additional protection of the critical area
from the proposed development; and
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L18-0056 Critical Areas Update PC Staff Report
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iii) The interrupted buffer does not provide significant hydrological, water quality
and wildlife buffer functions relating to the portion of the buffer adjacent to the
critical area.
III. cue callly (Hazardous re
Reference to mapping sources added and protective provisions such as slope vegetation
protection and guidelines on erosion control and best management practices included.
Fish and it life abit t Conservati n reas
a) The city's list of fish and wildlife habitat conservation areas made consistent with
GMA definition
b) Reference to mapping sources added.
c) A requirement for a habitat assessment prepared by a qualified professional to
better reflect BAS so that buffers could be based on site specific conditions.
V, S ecial azrd Floo Areas
Reference added to Special Hazard Flood Areas TMC Chapter 16.52; and floodplain
habitat assessment requirements included.
VI. ousek ep'in Co a Amen nts
Vesting:
Language added to clarify that only submittal of a complete building permit vests a
project to critical areas code. For instance, if a short plat is approved but homes are not
constructed and the code is updated, any future development is subject to the new
updated code. An exception added for projects that currently have a preliminary
approval but not final approval to be vested until the expiration of the preliminary
approval; provided building permits are submitted within one year of the final approval.
2. Expiration of decisions related to critical areas:
Five years term limit established for any approvals to be consistent with time limits for
permits obtained from the state and federal agencies.
3. Permitted uses changed to permitted activities section
4. Vegetation Protection section that includes tree retention, removal and
replacement requirements included:
Currently the tree retention, removal and replacement requirements are part of TMC
18.54, the Tree Code. A section is added that covers these subjects so that tree
removal, retention and protection in critical areas is all in one place and no cross -code
reference is required.
Tree protection section is similar to that which exists in 18.54.070 as is applicable to
critical areas.
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L18-0056 Critical Areas Update PC Staff Report
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Non-invasive vegetation retention (except in cases of defective trees) in sensitive areas
is in current code. Only change that will be made is clarification that tree retention on
steep slopes is also required.
Tree Replacement section is similar to what is required in the current shoreline code
(TMC 18.44.080).
5. Reorganization:
In order to improve the organization and make it easy to implement the code it is
reorganized to sequentially address 1. Mitigation sequencing; 2. What is allowed
outright/what requires Special Permission approval; 3. Criteria for approving deviations;
4. Mitigation requirements; 5. Monitoring
6. Penalties for unauthorized alterations:
Penalties for illegal clearing in critical areas added.
7. Non -conforming provisions:
New non -conforming thresholds for development in the wetland and stream buffers
established; and tied to incentives for improving the buffer.
a) Allow existing buildings to expand vertically to add upper stories in exchange for
buffer enhancement
b) Allow lateral expansion to the building side that is opposite of critical area up to a
maximum of 1000 sq. ft; in exchange for buffer enhancement. Further this option is
limited to situations where the buffer width is at least 75 percent of the required
buffer.
c) Allow lateral expansion along the existing building lines in exchange for buffer
enhancement; and limit the sq. ft. of new intrusion into the buffer to less than 50
percent of the current intrusion or 500 sq. ft, whichever is less. Further this option is
limited to situations where the buffer width is at least 75 percent of the required
buffer.
d) Allow enclosing within existing footprint in exchange for buffer enhancement.
8. Inventory update:
Add requirement for the applicant to provide surveyed data for maintenance of the City's
Critical Areas inventory map
RECOMMENDATION
Hold the public hearing on the proposed changes and determine whether any additional
changes should be added based on public testimony. Staff will return with a comment matrix
and revised drafts for the Planning Commission to review and forward to the City Council.
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