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City of Edmonds
Plan Review Corrections
20696-j!q;7
Plan Check # L5—S— Date
Project Name/Address
Contact Person/Address IVAiII110 1-,,1MZV1-
Department: Buildine M EngineeringEl
Reviewer J1---61zPb-z-
Planning [-] Fire [-] Public Works [-]
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9 Submit 2 sets of revised plans/documents to the Permit Coordinator.
ri Corrections may be made by red lining plans/documents on file with the City.
DATEFAXED (Attach fax transmittal) PAGE OF
23.80.040
Part H. Allowed Activities —
Geologically Hazardous Areas
23.80.040 Allowed activities —
Geologically hazardous areas.
The following activities are allowed in geo-
logically hazardous areas as consistent with
ECDC 23.40.220, Allowed activities, Chapter
19.10 ECDC, Building Permits — Earth Sub-
sidence and Landslide Hazard Areas, and
Chapter 18.30 ECDC, Storm Water Manage-
ment, and do not require submission of a criti-
cal area report:
A. Erosion and Landslide Hazard Areas.
Except as otherwise provided for in this title,
only those activities approved and permitted
consistent with an approved critical areas
report in accordance with this title shall be
allowed in erosion or landslide hazard areas.
B. Seismic Hazard Areas. The following
activities are allowed within seismic hazard
areas:
1. Construction of new buildings with
less than 2,500 square feet of floor area or roof
area, whichever is greater, and which are not
residential structures or used as places of
employment or public assembly;
2. Additions to existing single -story res-
idences that are 250 square feet or less; and
3. Installation of fences. [Ord. 3527 § 2,
2004].
Part 1H. Additional Report Requirements —
Geologically Hazardous Areas
23.80.050 Special study and report
requirements — Geologically
hazardous areas.
Critical area report requirements for geolog-
ically hazardous areas are generally met
through submission to the director of one or
more geotechnical engineering reports. In
addition to the general critical areas report
requirements of ECDC 23.40.090, critical
areas reports for geologically hazardous areas
must meet the requirements of this section and
Chapters 18.30 and 19. 10 ECDC as applicable.
Critical areas reports for two or more types of
critical areas must meet the report require-
ments for each relevant type of critical area.
Geotechnical report(s) submitted for the pur-
pose of critical areas review are required as
necessary in addition to reports, data and other
information mandated per ECDC Titles 18 and
19.
A. Preparation by a Qualified Professional.
A critical areas report for a geologically haz-
ardous area shall be prepared by an engineer or
geologist licensed in the state of Washington,
with experience analyzing geologic, hydro-
logic, and ground water flow systems, and who
has experience preparing reports for the rele-
vant type of hazard. Critical areas studies and
reports on geologically hazardous areas shall
be subject to independent review pursuant to
ECDC 23.40.090(B).
B. Area Addressed in Critical Areas
Report. The following areas shall be addressed
in a critical areas report for geologically haz-
ardous areas-
1. The project area of the proposed
activity; and
2. All geologically hazardous areas
within 200 feet of the project area or that have
the potential to be affected by the proposal.
C. Geological Hazards Assessment. A crit-
ical areas report for a geologically hazardous
area shall contain an assessment of geological
.hazards including the following site- and pro-
posal -related information at a minimum-
1. Site and Construction Plans. The
report shall include a copy of the site plans for
the proposal showing:
a. The type and extent of geologic
hazard areas, any other critical areas, and buff-
ers on, adjacent to, within 200 feet of, or that
are likely to impact the proposal;
b. Proposed development, including
the location of existing and proposed struc-
tures, fill, storage of materials, and drainage
facilities, with dimensions indicating distances
to the floodplain, if available;
(Revised 3105) 23-80
Edmonds Community Development Code
23.80.030
Figure 2
Slopes Extending Off Lots
Ifthd tde7ot top Of wsloo is.: IdWod off, of. a
subject property, them it shalLbwdalineated 200:
horizontal feet from the, property boundary or at
its natural, Iodation,
whichever is.-doser to the
subject parbel.
Toe Defined
,Natural
3. Any area potentially unstable as a
result of rapid stream incision or stream bank
erosion; and
4. Any area located on an alluvial fan,
presently subject to, or potentially subject to,
inundation by debris flow or deposition of
stream -transported sediments.
C. Seismic Hazard Areas. Seismic hazard
areas are areas subject to severe risk of damage
as a result of earthquake -induced ground shak-
ing, slope failure, settlement, soil liquefaction,
lateral spreading, or surface faulting. Settle-
ment and soil liquefaction conditions occur in
areas underlain by coliesionless, loose, or soft -
saturated soils of low density, typically in
association with a shallow ground water table.
[Ord. 3527 § 2, 2004].
23.80.030 Mapping of geologically
hazardous areas.
A. The approximate location and extent of
geologically hazardous areas are shown on the
city of Edmonds critical areas inventory. In
sut�ject
Parcel,
Top
Defined Here
addition, resources providing information on
the location and extent of geologically hazard-
ous areas in Edmonds include:
1. Washington Department of Ecology
coastal zone atlas (for marine bluffs);
2. U-S. Geological Survey geologic
maps, landslide hazard maps, and seismic haz-
ard maps;
3. Washington State Department of Nat-
ural Resources seismic hazard maps for West-
ern Washington;
4. Washington State Department of Nat-
ural Resources slope stability maps;
5. National Oceanic and Atmospheric
Administration tsunami hazard maps; and
6. Federal Emergency Management
Adatinistration flood insurance maps.
B. The critical areas inventory and the
resources cited above are to be used as a guide
for the city of Edmonds development services
department, project applicants and/or property
owners and may be continuously updated as
new critical areas are identified. They are a ref-
erence and do not provide a final critical area
designation. [Ord. 3527 § 2, 2004].
23-79 (Revised 3/05)
Edmonds Community Development Code
23.80.050
c. The topography, in two -foot con-
tours, of the project area and all hazard areas
addressed in the report; and
d. Clearing limits;
2. Assessment of Geological Character-
istics. The report shall include an assessment
of the geologic characteristics of the soils, sed-
iments, and/or rock of the project area and
potentially affected adjacent properties, and a
review of the site history regarding landslides,
erosion, and prior grading. Soils analysis shall
be accomplished in accordance with accepted
classification systems in use in the region. The
assessment shall include, but not be limited to:
a. A description of the surface and
subsurface geology, hydrology, soils, and veg-
etation found in the project area and in all haz-
ard areas addressed in the report;
b. A detailed overview of the field
investigations, published data, and references;
data and conclusions from past assessments of
the site; and site -specific measurements, tests,
investigations, or studies that support the iden-
tification of geologically hazardous areas; and
c. A description of the vulnerability
of the site to seismic and other geologic events;
3. Analysis of Proposal. The report shall
contain a hazards analysis including a detailed
description of the project, its relationship to the
geologic hazard(s), and its potential impact
upon the hazard area, the subject property, and
affected adjacent properties; and
4. Minimum Buffer and Building Set-
back. The report shall make a recommendation
for the minimum no-disturbance'buffer and
minimum building setback from any geologic
hazard based upon the geotechnical analysis.
D. Incorporation of Previous Study. Where
.a valid critical areas report has been prepared
within the last five years for a specific site, and
where the proposed land use activity and sur-
rounding site conditions are unchanged, said
report may be incorporated into the required
critical areas report. The applicant shall submit
a hazards assessment detailing any changed
environmental conditions associated with the
site.
E. Mitigation of Long -Term Impacts.
When hazard mitigation is required, the miti-
gation plan shall specifically address how the
activity maintains or reduces the preexisting
level of risk to the site and adjacent properties
on a long-term basis (equal to or exceeding the
projected lifespan of the activity or occupa-
tion). Proposed mitigation techniques shall be
considered to provide long-term, hazard reduc-
tion only if they do not require regular mainte-
nance or other actions to maintain their
function. Mitigation may also be required to
avoid any increase in risk above the preexist-
ing conditions following abandonment of the
activity.
F. Additional Technical Information
Requirements for Erosion and Landslide Haz-
ard Areas. In addition to the basic critical areas
report requirements for geologically hazard-
ous areas provided in subsections A through E
of this section, technical information for ero-
sion and landslide hazard areas shall meet the
requirements of Chapter 19. 10 ECDC and
include the following information at a mini-
mum:
1. Site Plan. The critical areas report
shall include a copy of the site plan for the pro-
posal showing:
a. The height of slope, slope gradient,
and cross-section of the project area;
b. The location of springs, seeps, or
other surface expressions of ground water on
or within 200 feet of the project area or that
have the potential to be affected by the pro-
posal; and
c. The location and description of
surface water runoff features;
2. Hazards Analysis. The hazards analy-
sis component of the critical areas report shall
specifically include:
a. A description of the extent and
type of vegetative cover;
b. A description of subsurface condi-
tions based on data from site-speci.fic explora-
tions;
23-81 (Revised,3/05)
23.80.050
c. Descriptions of surface and ground
water conditions, public and private sewage
disposal systems, fills and excavations, and all
structural improvements;
d. An estimate of slope stability and
the effect construction and placement of struc-
tures will have on the slope over the estimated
life of the structure;
e. An estimate of the bluff retreat rate
that recognizes and reflects potential cata-
strophic events such as seismic activity or a
100-year storm event;
f. Consideration of the run -out haz-
ard of landslide debris and/or the impacts of
landslide run -out on down -slope properties;
g. A study of slope stability including
an analysis of proposed cuts, fills, and other
site grading;
I h. Recommendations for building sit-
ing limitations; and
i. An analysis of proposed surface
and subsurface drainage, and the vulnerability
of the site to erosion;
3. Geotechnical Engineering Report.
The technical information for a project within
a landslide hazard area shall include a geotech-
nical engineering report prepared by a licensed
engineer that presents engineering recommen-
dations for the following:
a. Parameters for design of site
improvements including appropriate founda-
tions and retaining structures. These should
include allowable load and resistance capaci-
ties for bearing and lateral loads, installation
considerations, and estimates of settlement
performance;
b. Recommendations for drainage
and subdrainage improvements;
c. Earthwork recommendations
including clearing and site preparation criteria,
fill placement and compaction criteria, tempo-
rary and permanent slope inclinations and pro-
tection, and temporary excavation support, if
necessary; and
d. Nfitigation of adverse site condi-
tions including slope stabilization measures
and seismically unstable soils, if appropriate;
4. Erosion and Sediment Control Plan.
For any development proposal on a site con-
taining an erosion hazard area, an erosion and
sediment control plan shall be required. The
erosion and sediment control plan shall be pre-
pared in compliance with requirements set
forth in Chapter 18.30 ECDC.
G. Limited Report Requirements for Stable
Erosion Hazard Areas. At the director's discre-
tion, detailed critical areas report requirements
may be waived for erosion hazard areas with
suitable slope stability. Report requirements
for stable erosion hazard areas may be met
through construction documents that shall
include at a minimum an erosion and sediment
control plan prepared in compliance with
requirements set forth in Chapter 18.30
ECDC.
H. Seismic Hazard Areas. In addition to the
basic critical areas report requirements for
geologically hazardous areas provided in sub-
sections A through E of this section, a critical
areas report for a seismic hazard area shall also
meet the following requirements:
1. The site map shall show all known
and mapped active faults within 200 feet of the
project area or that have the potential to be
affected by the proposal.
2. The hazards analysis shall include a
complete discussion of the potential impacts of
seismic activity on the site (for example, forces
generated and fault displacement).
3. A geotechnical engineering report
shall evaluate the physical properties of the
subsurface soils, especially the thickness of
unconsolidated deposits and their liquefaction
potential. If it is determined that the site is sub-
ject to liquefaction, mitigation measures
appropriate to the scale of the development
shall be recommended and implemented. [Ord.
3527 § 2, 20041.
(R.evised 3/05) 23-82
Edmonds Community Development Code
23.80.070
Part IV. Development Standards —
Geologically Hazardous Areas
23.80.060 Development standards —
General requirements.
A. Alterations of geologically hazardous
areas or associated buffers may only occur for
activities that:
1. Will not increase the threat of the geo-
logical hazard to adjacent properties beyond
predevelopment conditions;
2. Will not adversely impact other criti-
cal areas;
3. Are designed so that the hazard to the
project is eliminated or mitigated to a level
equal to or less than predevelopment condi-
tions; and
4. Are certified as safe as designed and
under anticipated conditions by a qualified
engineer or geologist, licensed in the state of
Washington.
B. Critical Facilities Prohibited. Critical
facilities shall not be sited within geologically
hazardous areas unless there is no other practi-
cal alternative. [Ord. 3527 § 2, 20041.
23.80.070 Development standards —
Specific hazards.
A. Erosion and Landslide Hazard Areas.
Activities on sites containing erosion or land-
slide hazards shall meet the requirements of
ECDC 23.80.060, Development Standards —
General Requirements, and the specific fol-
lowing requirements:
1. Buffer Requirement. A buffer shall be
established from all edges of landslide hazard
areas. The size of the buffer shall be deter-
mined by the director consistent with recom-
mendations provided in the geotechnical
report to eliminate or minimize the risk of
property damage, death, or injury resulting
from landslides caused in whole or part by the
development, based upon review of and con-
currence with a critical areas report prepared
by a qualified professional.
a. Minimum Buffer. The minimum
buffer shall be equal to the height of the slope
existing within the project area or 50 feet,
whichever is greater;
b. Buffer Reduction. The buffer may
be reduced to a minimum of 10 feet when a
qualified professional demonstrates to the sat-
isfaction of the director that the reduction will
adequately protect the proposed development,
adjacent developments and uses and the sub-
ject critical area;
c. Increased Buffer. The buffer may
be increased where the director determines that
a larger buffer is necessary to prevent risk of
damage to proposed and existing develop-
ment;
2. Alterations. Alterations of an erosion
or landslide hazard area and/or buffer may
only occur for activities for which a hazards
analysis is submitted and certifies that:
a. The development will not increase
surface water discharge or sedimentation to
adjacent properties beyond predevelopment
conditions;
b. The development will not decrease
slope stability on adjacent properties; and
c. Such alterations will not adversely
impact other critical areas;
3. Design Standards. Development
within an erosion or landslide hazard area
and/or buffer shall be designed to meet the fol-
lowing basic requirements unless it can be
demonstrated that an alternative design that
deviates from one or more of these standards
provides greater long-term slope stability
while meeting all other provisions of this title.
The requirement for long-term slope stability
shall exclude designs that require regular and
periodic maintenance to maintain their level of
function. The basic development design stan-
dards are:
a. The proposed development shall
not decrease the factor of safety for landslide
occurrences below the limits of 1.5 for static
conditions and 1.2 for dynamic conditions. If
stability at the proposed development site is
below these limits, the proposed development
23-83 (Revised 3105)
23.80.070
shall provide practicable approaches to reduce
risk to human safety and improve the factor of
safety for landsliding. In no case shall the
existing factor of safety be reduced for the sub-
ject property or adjacent properties;
b. Structures and improvements shall
be clustered to avoid geologically hazardous
areas and other critical areas;
c. Structures and improvements shall
minimize alterations to the natural contour of
the slope, and foundations shall be tiered
where possible to conform to existing topogra-
phy;
d. Structures and improvements shall
be located to preserve the most critical portion
of the site and its natural landforms and vege-
tation;
e. The proposed development shall
not result in greater risk or a need for increased
buffers on neighboring properties;
f. The use of retaining walls that
allow the maintenance of existing natural
slope area is preferred over graded artificial
slopes; and
g. Development shall be designed to
minimize impervious lot coverage;
4. Vegetation Retention. Unless other-
wise provided or as part of an approved alter-
ation, removal of vegetation from an erosion or
landslide hazard area or related buffer shall be
prohibited;
5. Seasonal Restriction. Clearing shall
be allowed only from May Ist to October Ist
of each year; provided, that the director may
extend or shorten the dry season on a case -by -
case basis depending on actual weather condi-
tions, except that timber harvest, not including
brush clearing or stump removal, may be
allowed pursuant to an approved forest prac-
tice permit issued by the city of Edmonds or
the Washington State Department of Natural
Resources;
6. Point Discharges. Point discharges
from surface water facilities and roof drains
onto or upstream from an erosion or landslide
hazard area shall be prohibited except as fol-
lows:
a- Conveyed via continuous storm
pipe downslope to a point where there are no
erosion hazard areas downstream from the dis-
charge;
b. Discharged at flow durations
matching predeveloped conditions, with ade-
quate energy dissipation, into existing chan-
nels that previously conveyed storm water
runoff in the predeveloped state; or
c. Dispersed discharge upslope of the
steep slope onto a low -gradient, undisturbed
buffer demonstrated to be adequate to infiltrate
all surface and storm water runoff, and where
it can be demonstrated that such discharge will
not increase the saturation of the slope; and
7. Prohibited Development. On -site
sewage disposal systems, including drain
fields, shall be prohibited within erosion and
landslide hazard areas and related buffers.
B. Earth Subsidence and Landslide Hazard
Area. In addition to the requirements of this
chapter, development proposals for lands
located within the earth subsidence and land-
slide hazard area as indicated on the critical
areas inventory shall be subject to the provi-
sions of Chapter 19.10 ECDC.
C. Seismic Hazard Areas. Activities pro-
posed to be located in seismic hazard areas.
shall meet the standards of ECDC 23.80.060,
Development Standards — General Require-
ments. [Ord. 3527 § 2, 20041.
(Revised 3/05) 23-84
Figure 23.80.000
CITY OF EDMONDS CRITICAL AREAS
.Critical Areas Compliance Requirements*
h.
R,
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izW1
*Report requirements may be met through submission of a single critical area report or multiple reports 'in combination.
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