CRA19970123 Critical area recon report.pdf` Ic. 1,0",
CITY OF EDMONDS
121 5"' Avenue North, Edmonds WA 98020
Phone: 425.771.0220 ® Fax: 425.771.0221 ® Web: www.ci.eclnnoxtds.wcr.�'is
DEVELOPMENT SERVICES DEPARTMENT ® PLANNING DIVISION
Critical ass
Criticol Ar os 1-ile, Number.
De>termrrrinotian
Site l.ocotion
Tax Acc(.wnt Number
Property Owner
Applic ont
Critical Are as Present.
Site S cxipu
f:'lwA19970123 (update)
.Study Required
.11.0912t"Atrenue North
00548900002009
Richard and Barbara Stuart
PO Bax 2w36
"drnond,s, WA .98020
Richard and Barbara ,Stuart:
RI Geologically Hazordous Areas
i"":"rosiarr Hazard Are a,s
Immo landslide fl azcard 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 Hazard Area or Landslide Hazard Area), pursuant to Chapter
23.40 of the Edmonds Community Development Code (ECDC). 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. Cited sections of the Edmonds Community Development Code (ECDC) can be found on the City of Edmonds
website at www.ci.edrnonds,waAJS.
The subject property is part of a larger west facing slope which contains an existing residence that has been
constructed into the slope. There is a rockery on the east side of the residence and a failed rockery west of the
driveway leading into the residence. West of the driveway the property slopes down at approximately 44%
according to the City's LiDAR information. Do to the steepness of the slopes on the property; the site has been
identified as a potential landslide hazard area. Soils on the property are identified as Alderwood gravelly sandy
loam 15 — 25% slopes. The soils together with the slopes also classify the site as a potential erosion hazard area.
Projects proposed further than 65' from the top or toe of the slope (50' buffer + 15' setback from the critical area)
may not require a geotechnical report to address critical areas issues (of course, other departments may require a
report to address their codes). Projects within 65' of the top of the slope will require a geotechnical report
consistent with the requirements identified below.
Allowed itie& Exempt Proposals
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 Requiremei,its
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. You may 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 tl Areas
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.
Landslide Hazard Areas are further defined in ECDC 23.80.020.A. 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.
Note 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 given in ECDC 23.80.060 and 23.80.070.
Lands-11de HazardAireas
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. 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.
Determination: Studyi
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 the illegal removal of trees may result in penalties and steep fines (ECDC 18.45.070,
ordinance #.3828).
Kernen Lien, Associate Planner
Name, Title
Sign
August 11, 2011
Date
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