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Delineation / Mitigation / Restoration / Habitat Creation / Permit Assistance 9505 19th Avenue S.E.
Suite 106
Everett, Washington 98208
(425) 337-3174
Fax (425) 337-3045
October 9, 2017
Linda Fabregas
15931 72nd Ave W
Edmonds, WA 98026
RE: Site Assessment and Functional Analysis: Snohomish County Tax ID
#00513300003616
On September 19, 2017, Wetland Resources, Inc. (WRI) conducted an on -site assessment and
functional analysis for the above referenced parcel, located at 15931 72nd Ave W in Edmonds,
WA. The purpose of this investigation was to respond to comments provided in Plan Review
Comments RE: Plan Check BLD20170946, received from the City of Edmonds Planning
Division (dated August 10, 2017).
SITE DESCRIPTION
The subject property is accessed from the west via 72nd Ave W. It contains a single-family
residence and associated outbuildings. The site slopes generally to the west. Soils on the site are
mapped by the NRCS web soil survey as Alderwood gravelly sandy loam, 8-15 percent slopes,
and Alderwood-Everett gravelly sandy loam, 25 to 70 percent slopes. Surrounding land use
consists of single-family residential use and undeveloped land.
SITE ASSESSMENT AND FUNCTIONAL ANALYSIS
Wetland and Buffer Assessment
The review letter received from the City of Edmonds requested assessment of a previously
identified Category II wetland located on the south side of N Meadowdale Road (across the
street from the subject site) that could cast a buffer onto the subject property. This wetland occurs
off -site on private property and was assessed from the public right-of-way of N Meadowdale
Road. The wetland could not be directly observed from the road, but it appears to occupy a
ravine located approximately 40 feet south of N Meadowdale Road. The tree canopy over the
ravine consists primarily of red alder (Alnus rubra, FAC). The area adjacent to N Meadowdale
Road is dominated by big leaf maple (Acer macrophyllum, FACU), Western red cedar (7huja plicata,
FAC), beaked hazelnut (Corylus cornuta, FACU), salmonberry (Rubus spectabilis, FAC), red
elderberry (Sambucus racemosa, FACU), red huckleberry (Paccinium parr/ifolium, FACU), European
mountain ash (Sorbus aucuparia (N/I), cherry laurel (Prunus laurocerasus, N/I), Himalayan blackberry
(Rubus armeniacus, FAC), trailing blackberry (Rubus ursinus, FACU), and English ivy (Hedera helix,
FACU).
Wetland Resources, Inc. 1 15931 72nd Ave W
October 9, 2017 WRI #17244
Functional Analysis
As noted in the review letter from the City of Edmonds Planning Division, Edmonds Community
Development Code (ECDC) 23.40.220.C.4 states:
"Development Proposal within Interrrupted Stream or Wetland Buffers. Adjacent areas that may be physically
separated from a stream or wetland due to existing legally established structures or paned areas may be exempted
from the prescribed buffer widths if proven scientifically to be functionally isolated from the stream or wetland. The
director will require the applicant to provide a site assessment and functional analysis documentation report by a
quali zed critical area consultant that demonstrates the interrupted buffer area is functionally isolated. The director
shall consider the hydrologic, geologic, and/or biological habitat connection potential and the extent and permanence
of the physical separation."
The subject property is physically separated from the wetland by an existing paved roadway (N
Meadowdale Road). Any portion of wetland buffer that would extend north of N Meadowdale
Road onto the subject property would not provide significant protection to wetland functions.
The basis of this assessment comes from review and analysis of Best Available Science on the
topic of buffer functions. Chapter 5 of the Washington State Department of Ecology Guidance
Document entitled "Freshwater Wetlands in Washington State Volume 1: A Synthesis of the Science"
provides a comprehensive analysis of buffer functions. The following, taken directly from the
aforementioned document, is a list of the functions provided by buffers: 1.) removing sediment;
2.) removing excess nutrients; 3.) removing toxics; 4.) influencing microclimate, 5.) maintaining
adjacent habitat; 6.) screening adjacent disturbances; and 7.) maintaining habitat connectivity.
Functions numbered 1-3 relate to water quality improvement. Any portion of the buffer that
would extend north of N Meadowdale Road is physically isolated from the wetland. Surface
water from the subject property flows into the storm drainage system north of N Meadowdale
Road, whereas surface water south of N Meadowdale Road flows into the subject wetland. Water
from the subject wetland enters the storm drainage system and merges with the stormwater from
the subject property down gradient of the wetland. Therefore, any portion of the buffer that
might extend north of N Meadowdale Road provides no water quality improvement benefit to
the wetland located south of the road.
Function 4 relates to the influence of the buffer on microclimate. The presence of N Meadowdale
Road interrupts the microclimate created by vegetation adjacent to the wetland, disconnecting it
from the microclimate occurring across the road from the wetland. Therefore, any portion of the
buffer that may occur north of the road does not influence the microclimate of the subject
wetland.
Functions numbered 5-7 relate to wildlife habitat. Buffer isolation created by the road eliminates
connectivity of the subject property to the wetland for all but avian species. Due to the
disconnection, any portion of the buffer that may occur north of the road does not provide a
significant influence on wildlife habitat functions of the wetland.
Wetland Resources, Inc. 2 15931 72" d Ave W
October 9, 2017 WRI #14136
The existing paved roadway of N Meadowdale Beach Road is a permanent feature and
functionally isolates the wetland south of the road from the subject property. Therefore, the
buffer of the wetland should not extend beyond the limits of the southern edge of N Meadowdale
Beach Road.
USE OF THIS REPORT
This Site Assessment and Functional Analysis is supplied to Linda Fabregas as a means of
determining the presence of on -site and adjacent critical areas as required by the City of
Edmonds during the permitting process. This report is based largely on readily observable
conditions and, to a lesser extent, on readily ascertainable conditions. No attempt has been made
to determine hidden or concealed conditions.
The laws applicable to critical areas are subject to varying interpretations and may be changed at
any time by the courts or legislative bodies. This report is intended to provide information
deemed relevant in the applicant's attempt to comply with the laws now in effect.
This report conforms to the standard of care employed by ecologists. No other representation or
warranty is made concerning the work or this report and any implied representation or warranty
is disclaimed.
Wetland Resources, Inc.
Joie Goodman
Associate Ecologist
John Laufenberg, PWS
Principal Ecologist
Wetland Resources, Inc. 3 15931 72"d Ave W
October 9, 2017 WRI # 1413 6