HomeMy WebLinkAbout921182027 Geotech AssessmentGeorge Edwards
Habitat Management Plan
Parcel # 921 182 027
Apri12006
Prepared for:
George Edwards
14 A Chase Drive
Lakewood, WA 98498
.~. ~:
George Edwards
Habitat Management Plan
Parcel #921 182 027
Apri12005
1.0 Introduction
1.1 Site Description
The 1+ acre site is located an Old Oak Bay Road. The roughly rectangular parcel slopes
to the eastern boundary and is adjacent to the shoreline of Oak Bay. Access to the parcel
is from a short driveway on an easement along the southern edge of the parcel.
A Type 5 stream (designation by Ross Goodwin Department of Natural Resources) lies at
the bottom of a steep slope from Old Oak Bay Road.. The stream flows to the north to a
flat grassy Swale where the stream forks; the main channel continues to east and off site
towards Oak Bay. The left fork of the stream appears to ga subsurface at after it flows
into a flat Swale. The stream originates upslope as roadside runoff and passes through a
culvert directed to the parcel. During the April water was flowing in as a shallow sheet
flaw approximately 9 feet wide.
The majority of the stream buffer is heavily vegetated with native species; in some
locations salmonberry was over 6 feet tall. The remainder of the .parcel below the stream
slopes gently towards Oak Bay. Several large maples, grand and Douglas' firs with a
healthy understory of native species were observed. Parts of the parcel that were
previously cleared or impacted are covered with Himalayan blackberries and other weedy
species. .
1.2 Site Development Plans .
A single family residence is planned for this site. A buffer reduction from. the 50 foot
easement will be required to access a building site via the existing easement. The
building envelope will also fall within the buffer to allow for sufficient setback from the
septic site location which has already been installed.
2.0 Habitat Management Plan
This Habitat Management. plan has been prepared to meet the requirement outlined in the
Jefferson County UDC (Adopted January 2041(Section 3.6.8.g. Protection Standards. (6)
Reducing Buffer Widths.) The UDC states that "Under no circumstances shall buffer widths be
reduced by more than twenty-five percent (25%)". The proposed reduction is from a 50 foot
buffer to a 40 foot buffer and is within the standards outlined above.
2.1 Impact Analysis
The construction process will impact approximately 1,800 square feet (1 SO feet wide by
lU feet deep), within the 50-foot buffers of the Type 5 stream. This buffer area is
Habitat Management Plan George Edwards
Report File Number 2006-0410 1 Olympic Wetland Resources, Inc.
required to accommodate a building site and access driveway. Impacts to the buffer are
unavoidable but will be minimized using Best Management Practices (BMP's) during the
construction process as outlined below in this report.
Field findings reveal that the azea to be reduced has been historically impacted by
clearing and now consists ofnon-native Himalayan blackberries.
2.2 Proposed Enhancement Site
After development all areas adjacent to the remaining buffer should be carefully
revegetated with native species. No parts of the stream buffer should be altered or
cut, but should remain in a natural state.
Native trees and shrubs that would be appropriate for this parcel include red-
flowering currant, vine maples, red-elderberry, cedars, and firs.
2.3 Project Goals and.Objectives
The goals and objectives are as follows:
• to retain at least 40 feet of existing buffer which is currently in a natural state;
• increase diversity of plant species with appropriate native trees and shrubs after
construction incomplete;
• to remove aggressive non-natives established on site, including Himalayan
blackberries;
• to provide protective measures during and after the construction process to
minimize impacts to the Type 5 stream or buffers (BMP's);
2.4 Best Management Practices
During and after the construction process Best Management Practices should be implemented as
outlined below:
Best Management Practices (BMP's}
Conservation Practices
1. Avoid or control soil loss and protect water quality from degradation caused by nutrients,
animal waste, toxins, and sediment; and
2. Avoid or minimize adverse impacts to surface'water and ground water flow, and
circulation patterns; and
3. Avoid or control the movement of sediment and erosion control caused by land alteration
activities; and
4. Avoid or minimize adverse impacts to the chemical, physical, and biological
characteristics of critical areas.
5.
BMP's are those practices as defined by the State of Washington Department of Agriculture, State of
Washington Department of Ecology, State of Washington Department of Fish and Wildlife, Jefferson County
conservation district, and other professional organizations.
Habitat Management Plan George Edwards
Report File Number 2005-0410 2 Olympic Wetland Resources, Inc.
3.0 Summary
A Type 5 stream that crosses the subject property will have buffer restrictions. This stream was
not previously mapped on the Jefferson County Critical Areas Maps but was recently classified
by Ross Goodwin at DNR. A buffer reduction from this Type 5 stream is required in order to
provide adequate access to a potential building envelope that is outside the setbacks of an
installed septic system. The standazd buffer is 50 feet; the reduction requested will be a
reduction of 10 feet to a 4D foot buffer. This reduction is within the allowable buffer reduction
of less than 25°!0. If the remaining buffer remains intact and native vegetation is added after the
construction process is complete there should be no significant damage to the functions and
values of the streamside buffer.
The final authority over buffer reduction and approval of this Habitat Management Plan rest with
Jefferson County Department of Community Development. If I can be of further assistance
please do not hesitate to call.
Dixie Llewellin
Principal Biologist, Olympic Wetland Resources, Inc.
Certified for Wetland Delineation, 1987 Manual
Wetland Training Institute, June 1995
Habitat Management Plan George Edwazds
Report File Number 2006-0410 3 Olympic Wetland Resources, Inc.
~' ~, ` Olympic Weiland Resources, Inc T~~: Findings Map
Parcel #921 182 02? ~~~As Indicated ~~
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George Edwards April 2006
360 385-6437
`~' dixie@cablespeed.aom 14A Chase Drive
Lakewood WA 98498 ~ #~ 2006-0410
Oak
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.•-'~'•.~____~ Approximate Location
of Type 5 Stream
Reduced Buffer (40')
All stream and buffer locations
and are approximate;
to establish exact location
a formal survey is required
Septic
Location