CRA-2011-0062 erosion-landslide.pdf.11 C
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121 5`r' Avenue North, Edmonds WA 98020
Phone: 425.771.0220 o Fax: 425.771.0221 - Web: wvvvv.ci,e.��1����uond�s,wa,us
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DEVELOPMENT SERVICES DEPARTMENT m PLANNING DIVISION
Critical AreasReconnaissance
Critical Areas File Number,
Determination
Site l.cacation
Tax Account Number
Property Owner
Applicant
Critical Areas Present,
Site Description
CRA20110063
Study Required
17.500 72"" Ave. W
0045 6000000900
Michael.]. Weisman
Michael.]. Weisman
I I Geologically Hazardous Areas
Erosion h1ozard Areas
0 Landslide Hazard Areas
During review and inspection of the subject site, it was found that the site may contain (or be adjacent to) critical
areas, including Geologically Hazardous Areas (Erosion and Landslide Hazard Areas), pursuant to Chapter 23.40
and 23.80 of the Edmonds Community Development Code (ECDC). Cited sections of the Edmonds Community
Development Code (ECDC) can be found on the City of Edmonds website at www..c.J..,. ,c),rr�c,i
The associated LiDAR map indicates the subject parcel slopes down generally from the east to the west toward
Puget Sound. The eastern half of the site is fairly level, particularly along 72"d Avenue West. The western half of
the parcel falls off steeply to the west and north with grades ranging from 15% to nearly 60%. Soils on the
property are identified as Alderwood urban land complex (2 — 8 % slope) on the northeastern half of the parcel
while the southwestern half is underlain by Alderwood gravelly sandy loam series (15% - 25% slope). Those areas
of the site with slopes between 15% and 40% are classified as a potential erosion hazards while the slopes on the
western and northern edges of the parcel have slopes in excess of 40% which are classified as a potential landslide
hazards.
Projects proposed further than 65' from the top or toe of the potential landslide hazard (50' buffer + 15' setback
from the critical area) may not require a geotechnical report to address critical areas issues (other departments
may require a report to address their codes).
Allowed ActivitiesExempt
Certain activities are allowed in or near critical area buffers as specified in ECDC 23.40.220. Similarly, certain
development proposals may be exempt from Critical Areas requirements (ECDC 23.40.230). If you have any
questions about whether your proposed development qualifies as an allowed or exempt activity, please contact
a Planner for more information.
General Report ReqUirements
Critical Areas Reports identify, classify and delineate any areas on or adjacent to the subject property that may
qualify as critical areas. They also assess these areas and identify any potential impacts resulting from your specific
development proposal. If a specific development proposal results in an alteration to a critical area the critical
areas report will also contain a mitigation plan. You have the option of completing the portion of the study that
classifies and delineates the critical areas and waiting until you have a specific development proposal to complete
the study. You may also choose submit the entire study with your specific development application. Please review
the minimum report requirements for all types of Critical Areas which are listed in ECDC 23.40.090.D. There are
additional report requirements for different types of critical areas (see below). Note that it is important for the
report to be prepared by a qualified professional as defined in the ordinance. There are options on how to
complete a critical areas study and an approved list of consultants that you may choose from. Please contact the
Planning Division for more information. General Mitigation Requirements for all Critical Areas are discussed in
ECDC 23.40.110 through 23.40.140.
Erosion
iHazard Are -as
It appears that this property contains or is adjacent to an Erosion Hazard Area. Geologically hazardous areas
include areas susceptible to erosion, land sliding, earthquake, or other geological events. They pose a threat to the
health and safety of citizens when incompatible development is sited in areas of significant hazard. Such
incompatible development may not only place itself at risk, but also may increase the hazard to surrounding
development and use.
Erosion Hazard areas include Alderwood and Everett series soils on slopes of 15 percent or greater, among others.
In addition to the general requirements for Critical Areas reports referenced above, specific Critical Area report
requirements for Erosion Hazard Areas (which are one of the Geologically Hazardous Areas) are provided in ECDC
23.80.050.
(Vote that Stable Erosion Hazard Areas may have limited report requirements at the director's discretion. At a
minimum an erosion and sediment control plan prepared in compliance with the requirements in ECDC Chapter
18.30 shall be required.
Development is restricted within an Erosion Hazard Area and must meet additional criteria. For erosion hazard
areas with suitable slope stability, an erosion and sediment control plan prepared in compliance ECDC 18.30 will be
considered to meet the Critical Areas "Study Required" determination. The determination of "suitable slope
stability" will be made by both the Planning and Engineering divisions of the City of Edmonds. In areas where the
slope stability is not suitable, projects within Erosion Hazard Areas will require a report by a licensed Geotechnical
Engineer or other qualified professional. Note that it is important for the report to be prepared by a qualified
professional as defined in the ordinance. Report requirements are given in ECDC 23.80.050, and more generally in
ECDC 23.40.090.D. Development standards are provided in ECDC 23.80.060 and 23.80.070.
Page 1 2
Landslide e
Development is restricted within a Landslide Hazard Area and its buffer. Projects that will intrude into these areas
will require a report by a licensed Geotechnical Engineer. Geologically hazardous areas include areas susceptible
to erosion, land sliding, earthquake, or other geological events. They pose a threat to the health and safety of
citizens when incompatible development is sited in areas of significant hazard. Such incompatible development
may not only place itself at risk, but also may increase the hazard to surrounding development and use.
The criteria that are applied depend on the amount that the buffer is reduced. The buffer can be reduced to a
minimum of ten (10) feet (with an additional 15' building setback per ECDC 23.40.280) if a report is prepared that
meets the standards listed in ECDC 23.80.050). The alteration must also meet the requirements listed ECDC
23.80.060. In addition, proposals to reduce the buffer to less than ten (10) feet must comply with the design
standards listed in ECDC 23.80.070.A.3.
Determination: Stud
This review applies to the entire subject parcel. Depending on the location and project proposed relative to the
identified critical areas, certain studies and reports may be required. Please contact the Planning Division at
425.771.0220 if and when you have a specific development proposal for this site in order to discuss the various
permits that will be required. Please note that tree removal on sites containing critical areas may first require a
tree cutting permit and that illegal removal of trees may result in penalties identified in ECDC 18.45.070.
Michael Clugston, AICP r, J°� July 18, 2011
Name, Title
Signature
Date
ZME