HomeMy WebLinkAboutOHWM Determination 821355029Page 1 of 12
Dropp Ordinary High Water Mark Determination
March 5, 2020
Prepared for:
Chase Dropp
103 River Run Road
Sequim, WA 98382
Regarding:
Jefferson County Parcel 821355029
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Introduction
On February 27, 2020, Ioana Bociu and Kimberly McClurg of Marine Surveys & Assessments
(MS&A) conducted an Ordinary High Water Mark (OHWM) Determination for Parcel
821355029 in Port Ludlow, Washington (Figure 1). The area around the proposed building
footprint and the area near a mapped stream on site were surveyed to determine if any OHWM
indicators were present to determine buffer setbacks that may affect the proposed building
footprint.
Parcel 821355029 is assessed at approximately 5.02 acres in Section 35, Township 28 N, 1E. A
stream is mapped on the parcel, which flows approximately northeast to connect to another
stream offsite (Figure 2). This stream on site was typed by DNR in 2001 as a Type 5 (now
considered type Ns) stream (Appendix A).
Methodology
Upon arrival at the property, site pictures were taken to document vegetation and substrate type,
along with a written general description of the site. The survey was conducted between 0930 and
1130 hours.
Starting at the western end of the property and continuing east is a depression that starts out
small and shallow (possible old riverbed) with a gentle slope that gets deeper with steeply sloped
sides as you continue east across the parcel. On the eastern side of the parcel, the ground starts to
slope more steeply (to a ravine on the very eastern side of the parcel) and is covered with
Himalayan blackberry which made it challenging to access the mapped steam from the eastern
side (Figure 2). MS&A staff followed the depression as far as possible starting west and
continuing east until staff encountered impenetrable Himalayan blackberries across the
depression that were too thick to navigate. The survey endpoint was close to where the stream is
mapped to start (Figure 3).
The depression and surrounding areas were inspected for the three criteria for identifying
OHWM: geomorphic/hydrologic indicators of high flow regime, soils, and vegetation.
This assessment is congruent with the Department of Ecology “Determining the Ordinary High
Water Mark for Shoreline Management Act Compliance in Washington State” manual.
Findings
Along the section of the depression that staff were able to survey, it was completely dry and
there were no marks along the sides or bottom indicating commonly occurring high flows. The
slope stability along the ravine is indicated as “intermediate” by the Ecology Coastal Atlas
Mapper. Intermediate slopes are defined as “steeper than 15 percent except where conditions
such as weaker material and/or abundant groundwater exist. Identified areas include slopes of
sand and gravel, till, or thin soils over bedrock which have no known failures”. This survey was
done after a period of heavy rain so even a low flow stream would be expected if one was
present.
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Dominant vegetation in the depression was sword fern (Polystichum munitum.) and Himalayan
blackberry (Rubus armeniacus), both of which are upland plant species that are not typically
found in areas of ordinary inundation.
There was no transition between channel bed material (i.e. cobble and gravel) and finer
sediment. There was a thick layer of relatively dry leaf litter on the bottom that showed no signs
of water marks. Thick roots were also present under the soil surface; no cobble or gravel.
No evidence of a stream was noted upland near the proposed building footprint and no wetland
vegetation was present. Vegetation observed includes sword fern (Polystichum munitum.),
Oregon grape (Mahonia nervosa sp.), purple foxglove (Digitalis purpurea) and coniferous tree
species.
Conclusion
Due to the lack of any OHWM indicators of a stream that would warrant a 50-75 ft buffer, the
proposed building footprint is appropriately placed so as not to fringe upon a critical area.
If any trees are proposed to be cleared on the eastern side of the parcel where staff were not able
to survey, we recommend reaching out to DNR to re-evaluate the stream type/presence since the
last typing was done in 2001.
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Figure 1. Vicinity Map
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Figure 2. Jefferson County Parcel Map Showing Elevation Contours & Mapped Streams
(subject parcel outlined in red)
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Figure 3. Map of Survey Points
End survey pt
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Photo 1. Following the ravine showing blackberry and sword fern
Photo 2. Near the end of the surveyable portion of the ravine
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Photo 3. Survey end point (facing east)
Photo 4. Soil at the bottom of the ravine
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Appendix A. 2001 DNR Stream Typing Report
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