DNS REVIEWED PLN RESUB7 BLD2020-0733+PLN_Response+2.8.2022_4.03.50_PM+2669630 (2)416
CITY OF EDMONDS
PLAN REVIEW COMMENTS
PLANNING DIVISION
425.771.0220
DATE: January 13, 2022
TO: Christopher Pichner; CHRISPICHNER@YAHOO.COM
FROM: Michele Q. Szafran, Planner
michele.szafran(@edmondswa.gov
RE: Plan Check BLD2020-0733
8120 Talbot Rd.
Retaining Walls
On behalf of the Planning Division, I have reviewed the resubmittal on December 22, 2021, for the
above referenced building permit application and have also taken into consideration the email
response provided from Thomas McDonough dated January 6, 2022. Based on the email response
provided, my comments below are made under the assumption that all retaining walls will be removed.
Additional comments may follow once revised plans are submitted. Please respond to the following
items:
1. Site Plan
Site plan (Figure 6, attached) needs to expand the planting area to include the area of all
the removed walls. These areas need to be restored with plantings consistent with the
critical area consultant recommendations. The areas where the retaining walls were
removed an additional 30 kinnikinnick plants were planted. Figure 6 is expanded and
color coded to correspond to the planting plan zones.
Show erosion control measures as recommended by the Geotech. Response taken
from Geotech report dated January 26, 2022.
The walls have been completely removed from the site, and the surface regraded to
resemble previous natural slope grade. The removal has occurred during a
persistent dry period of weather. No measurable rainfall has impacted the site during
demolition. Replanting appears to have been completed, with new tree starters and
vegetation cover having seeded and planted, with mulch over the majority of
exposed surface sails
• If trees are to be removed in the future the property owner must inquire with the city
regarding tree removal permit requirements. No trees will be removed.
2. Critical Area Report Requirements: Include the area subject to the LLA as applicable.
Stream Report: The restoration planting plan prepared by Alexander Callender dated
December 21, 2020 must be expanded (see Figure 6 and pgs. 16-20 attached) to
include the areas of the removed walls and the cost estimate must be updated as
noted on page 19 of the stream report. An additional 30 kinnikinic plants will be
added to the planting plan and positioned above zone 3 to provide ground cover for
the area of the vacated retaining walls. The kinnikinic plants will be speced 2' apart
to accommodate the average growth size of the plant to maximize the potential
coverage needed.
• Geotech Report: Provide an updated site plan to the Geotech regarding the full scope
of work along with the required planting plan as noted above. Please have Geotech
specifically address ECDC 23.80.060 and 23.80.070. The Geotech must also address
wet season work. The report dated August 24, 2021, provided by Nelson GeotechnicaI
Associates, Inc. (2" $, Pg. 6.) discusses the moisture -sensitive soils, the Geotech
recommends that demo work take place during dry weather. If work is to be
performed during the wet weather season, then the Geotech must address this.
Quality Geo was provided an updated site plan, drafted by McDonough's Law
Office on 01/13/2022. The removal has occurred during a persistent dry period
of weather. No measurable rainfall has impacted the site during demolition.
Geotech specifically address ECDC 23.80.060 and 23.80.070 and noted the
following.
Geotech specifically address ECDC 23.80.060 and 23.80.070 and noted the following.
ECDC 23.80.060
23.80.060 Development standards — General requirements.
Geotech performed general site reconnaissance to consider any indications of
surface degradation or large-scale slope instability. No indications of deep-seated
displacement were observed to cross within the slope or near to the residence.
Topography was generally consistent and lacking: significantly over steepened
areas, channelized runout zones, tension cracks, or hummocky zones. No obvious
evidenceof rotational or translational failures or major toppling hazards was
observed on the slopes in the proximity of the home. No significant failure
features were observed onadjacent slope areas visible from the subject property
during the visit. Review of available LiDAR imagery did not reveal any obvious
historic or recent movement.
B. Critical Facilities Prohibited. Critical facilities shall not be sited within geologically
hazardous areas unless there is no other practical alternative. [Ord. 4026 § 1 (Att. A),
2016; Ord. 3527 § 2, 2004]. N/A
23.80.070 Development standards — Specific hazards.
A. Erosion and Landslide Hazard Areas. Activities on sites containing erosion or landslide
hazards shall meet the requirements of ECDC 23.80.060, Development standards -- General
requirements,and the specific following requirements:
1. Minimum Building Setback. The minimum setback shall be the distance required to
ensure the proposed structure will not be at risk from landslides for the life of the structure,
considered to be 120 years, and will not cause an increased risk of landslides taking place on
or off the site. A setback shall be established from all edges of landslide hazard areas. The
size of the setback shall be determined by the director consistent with recommendations
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 concurrence with a critical areas report prepared by a qualified
professional;
No new dwellings or structures are proposed, and original surface grades have been
restored; therefore no setbacks will be encroached
2. Buffer Requirements. A buffer may be established with specific requirements and
limitations, including but not limited to, drainage, grading, irrigation, and vegetation. Buffer
requirements shall be determined by the director consistent with recommendations
provided in the geotechnicaI report to eliminate or minimize the risk of property damage,
death, or injury resulting from landslides caused in whole or part by activities within the
buffer area, based upon review of and concurrence with a critical areas report prepared by
a qualified professional;
3. Alterations. Alterations of an erosion or landslide hazard area, minimum building setback
and/or buffer may only occur for activities for which a hazards analysis is submitted and
certifies that:
a. The alteration will not increase surface water discharge or sedimentation to adjacent
properties beyond predevelopment conditions;
b. The alteration will not decrease slope stability on adjacent properties; and
C. Such alterations will not adversely impact other critical areas;
Geotech does not anticipate any impacts on the slope, and surface stabilization is
expected to exceed its original state
4. Design Standards within Erosion and Landslide Hazard Areas. Development within an
erosion or landslide hazard area and/or buffer shall be designed to meet the following 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 standards 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 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 subject 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 topography;
d. Structures and improvements shall be located to preserve the most critical portion of the
site and its natural landforms and vegetation;
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;
Geotech indicated in his report that the proposed improvements are expected to increase
the overall surface stability.
5. Vegetation Retention. Unless otherwise provided or as part of an approved alteration,
removal of vegetation from an erosion or landslide hazard area or related buffer shall be
prohibited;
No vegetation to be removed
6. Seasonal Restriction. Clearing shall be allowed only from May 1st to October 1st of each year;
provided, that the director may extend or shorten the dry season on a case -by -case basis
depending on actual weather conditions, except that timber harvest, not including brush
clearing or stump removal, may be allowed pursuant to an approved forest practice permit
issued by the city of Edmonds or the Washington State Department of Natural Resources; N/A
No clearing or removal
7. 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 follows:
a. Conveyed via continuous storm pipe downslope to a point where there are no erosion
hazard areas downstream from the discharge;
b. Discharged at flow durations matching predeveloped conditions, with adequate energy
dissipation, into existing channels 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
Geotech report on Erosion Controls & Wet Weather Work: Walls have been removed, and
planting plan completed at this time. Work was completed during consistently dry weather,
successfully avoiding erosional concerns. While no further work is anticipated, if additional
restoration or work is to be done in the future for upkeep, we recommend the following be
considered by the property owner at such time:
8. Prohibited Development. On -site sewage disposal systems, including drain fields, shall be
prohibited within erosion and landslide hazard areas and related buffers. N/A
Pichner Deck and Wall Installation Critical Area and Fabitat Management Plan
LANDSERVICES NIJ
120 STATE AVE NE #190QLYMPIA, IJA 98501
zt�r;E
F1171--, -- —
16
Land Services Northwest December 15, 2020
Picnner Deck and Wall Installation Critical Area and Habitat Management Plan
FIGURE 6
SITE PLAN IJITH PLANTINGZONES
<NOT A SURVEY)
Land Services Northwest 17
December 15, 2020
Pichner Deck and Wall Installation Critical Area and Habitat Management Plan
nstalled downslope from any disturbed earth and all earth disturbance will be limited to the
minimum necessary to achieve the purpose. No equipment or debris will be stored in the
buffer. Stormwater from the home and nearby impervious surfaces will be directed away from
the area until the vegetation has established. The bare slope will be mulched with 4 inches of
mulch as soon as possible to prevent erosion. The work will be done when the danger of
turbid discharge to the stream is minimized in the late spring. The slopes will be watered as
needed to promote vegetation growth, but not so much that it will cause erosion.
All plant installations will be done by hand to minimize the potential for erosion. Mulch will be
applied four inches thick in order to improve moisture retention and reduce erosion.
The planting plan was conducted by hand with hand tools (shovels, trowles, rakes, ect... ) with
minimal foot traffic to minimize the impact on the stabilization of the critical area. Additionally,
an extra 30 kinnikinick plants were integrated into the planting plan to cover the areas of the
vacated retaining walls to bolster the stability of the slope above zone 3 of the planting plan
Fig 6.
8.0 MITIGATION PLAN
8.1 Impacts
The project will mitigate for the unavoidable impacts to 1,452 square feet of r parian habitat
through the removal of invasive species such as English ivy and Himalayan frlackberry and
replanting of 3,812 square feet with a robust combination of groundcover, shrubs and trees.
These plants will lead to an improvement of functions and diversity ove- the existing
conditions. A net gain or positive impact is expected in landscape roughness, habitat
screening, food source, nutrient uptake and aesthetics and overall habitat resilience (Figure
5). See olanting plan
8.2 Mitigation Objectives
We will mitigate for the removal of vegetation and the installation of lawn, steps and walls by
providing a revegetation plan that will meet the projects objectives to:
a. Improve habitat as a food source and screening for wildlife
b. Prevent erosion
c. Discourage intrusion/degradation of the buffer
d. Provide aesthetic benefits for the residents in the viewshed of the projec_
e. Stem the intrusion of invasive species a
8.3 Buffer Mitigation Functions
If the buffer enhancement performs as expected, we canexpect the following lift in functions. The semi quantitative
method used in the Wetland Rating System (ECY, 2014) was adapted as the resolution of performance lift is only
valid to the semi quantitative Low, Medium, and High
Table 1 - Buffer Functions Comparison Before and After Mitigation
Land Semites Northwest 18
December 15, 2020
lluiicA rcu
criteria
acreenmg'-""grient
Snags
Other
Structure
uptake
and
Habitat
Los
FeaturesBefore
7Medium
mitigatingmeasures
LOW
Meidum
Low
Medium
Medium
7allenualin
f1er
mitigating
High
High
Low
Medium
HighHigh
measures
Land Services Northwest 19
December 15, 2020
Pichrer Deck and Wall Installation Critical Area and Habitat Management Plan
8.4 Planting plan
The planting plan is provided. Trees will be planted at grade in holes 1-2 =imes the width of
the container or root ball. The mulch will be applied around each tree 2-4 inches deep in a
two -foot diameter around the tree with an edge to retain water. Rootbound trees will be cut
with sharp shears on the bottom in an x pattern to promote root growth. Four cuts will be
madte vertically to allow roots to spread. Trees will be thoroughly watered in after installation.
Shrl-bs will be installed in a similar manner.
The species selected are typical native northwest species that usually survive our summers;
however, it may be necessary to irrigate during the first two years to ensure survival. The
watering will be the minimal necessary to avoid creating erosion.
All retaining walls will be planted with kinnikinic to provide screening from the walls.
The first 15 feet along the creek will be planted with shrubs like Red osier dogwood, Pacific
ninebark and Twinberry to provide erosion protection and structure over the creek which will
provide allochthonous inputs like macroinvertebrates for the fish below.
The second thirty feet will be primarily trees like Sitka spruce, Western hem ock and
Western red cedar and Red flowering currant to provide shade that will attenuate
temperatures and eventually shade out the invasive species that have become prevalent in
the area.
The remaining area near the wails will be planted with groundcover (Salal and Roses) for
erosion protection.
Land Services (Northwest 20
December 15, 2020
Pichrer Deck and Wall Installation Critical Area and Habitat Management Plan
Table 2 Tree/Shrub Species Quantity and Spacing (3,812 sq ft)
on
rn
EHemlock
Scientific
Name
Tsuga
heterophyfla
Spacing
15 ft
Zone
2
Quantity
5
Cost per
unit
$5.04
Total
$25.00
Western reef
cedar
Thuja plicata
15 ft
2
5
$5.00
$25.00
Sitka spruce
sicea
sitchensis
15 ft
2
5
$20 40
$140 00
Clustered
rose
Nootka rose
Red
flowering
Rosa
pisocarpa
Rosa nutkana
Ribes
sanguineum
5 ft
5 ft
loft
3
3
2
5
5
10
$5.00
$5 04
$10.00
$25.00
$25 00
$100.00
current
Red osier
dogrrvood
Cornus alba
5 ft
20
5
$5.00
$100. 00
Pacific Nine
bark
Physocarpa
capitatus
5 ft
10
5
$5.00
$25.00
Twinoerry
Lonicera
involucrata
5 ft
1
5
$5.00
$25.00
kinnikinnick
Arctostaphylos
uva-ursi
2 ft
Walls+
20
$4.00
$80 40
Sal al
Goutheria
shallon
2 ft
3
20
$2.00
$40.40
Table 3 Total Costs
8.4 Performance Standards and Monitoring
The site will be monitored for five years with the as -built as Year 0. Photo points will be
established in 2 points that capture the overall condition of the planting area. Monitoring will
begin in the spring following the installation of the plants. Year 1 will requi-e 100 percent
survival. Year 2 must have 100 percent survival of planted native plants Years 3-5 will have
Land Services Northwest 19
December 15, 2020
Pichrer Deck and wall Installation Critical Area and Habitat Management Plan
an 80% survival rate, if the survival rate is not met in the final year, the deficit will be replanted,
and the site will be monitored for 1 more year. The survival percentage will include 10 percent
of a-iy native non-invasive volunteers. Monitoring will occur each spring after the plants have
sprouted leaves. Management will require prior removal of any blackberries, scotch broom or
holly or other invasive plants in the planting area and replacement of any dead plants as
reg4ired to meet the performance standards. A report of management actions and photos
of the area will go to the City of Edmonds Development Center within a month following each
site monitoring event.
The invasive removal area will be monitored as well. The invasive removal area will have any
non-native blackberries grubbed out. Holly will be cut down and any other invasives
encountered will be removed by hand.
A bond will be put in place to account for 15% of the cost of plant installation which with the
added 30 kinnikinnick plants come to a total of $700.00. Making the cost of the 15% bond at
$ 10 .00
9.0 CONTINGENCIES
The City will be consulted on any contingency measures that are developed. The report willbe in
an email by the applicant and will include pictures that illustrate the condition of the mitigation site.
Contingency/maintenance activities may include, but are not limited to.
1. Replacing plants lost to vandalism, drought, or disease, as necessary;
2. Irrigating the enhancement areas only as necessary during dry weather if plants appearto
be too dry, with a minimal quantity of water;
3. Remulching areas to protect from dry weather
4. Providing protection from rodents
10.0 CONCLUSIONS
Development activities accidently occurred in the riparian buffer when the applicant installedhis
steps, retaining walls and other landscape amenities. A geotechnical report has shown that these
structures can safely remain without destabilizing the slopes and causing damage to the property.
The applicant has carefully considered the best options forrevegetaling the slopes with vegetation
that is appropriate for limiting erosion and adding stability to the slope. This restoration will
provide benefits to the area in many different ways but most importantly, it will maintain the
functions and values of the stream for the citizens of Edmond.
Land Services Northwest 20
December 15, 2020