HomeMy WebLinkAbout1994.08.09 - Wetlands 3 & 4, CT Pipeline ProjectJ.
n . 3' Lisa P- alazzi Priricipai - ,'
Fourth Ave. Eau
R f ` • ' ! Suite 416
arp;a VA 98501ply
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MEMORANDUM
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aiMf ATE: August 9, 1994
0: - Paula ..Mackrow, 6HMi11,
011: "Lisa Falazzi, PRSW `
GARDING: Wetlands 3 aiid 4 CT Pipeline 'Project
a following information -is intended to provide .the justification for
elineation_and wetland •characteristic determination on Wet]artds 3 and 4,,.-as -,
hown on.the attached standard project-map.
n• brief summary: Wetland 3' is located directly adjacent_ to '(north-:6f)
iscovery. Road, starting about. 330 feet and ending about 420 feet east -of . the :. tom° orthwest corner of the intersection of Discovery Road -and Rainier Road. It
s formed as a result of seasonal storinwater backin u aloe Discover Road_
n a reach that apparently lacks a culvert to allow drainage- across Discovery.
source of. the water is seasonal runoff ibat collects' west of Rainier Road,
hen drains east through a -culvert' off Rainier 'Road. -The drainage area around -
he culvert and within the-60 feet wide Rainier easement does not meet the
hiee parameter - jurisdictional wetland requirements and therefore should not `
k ffect this project in terms of Army-Corps of Engineers (COE) regulatory
urposes. (Details below.)
etland 4 is located in a small drainage just south OfL Sims Way in the middle
of the Howard Street easement. The drainage primarily receives surface runoff
rom.Sims Way,- culverted stormwater from north of Sims Way, and likely also
ome subsurface seepage from nearby upland areas.' reas Wetland 4 's a Palustrine
HJ crub -Shrub wetland,,meeting all three wetland criteria, but is too small to-
e regulated as a wetland under the City of Port Townsend. Critical. Areas
rdinance. Under Nationwide Permitting rules, thg COE will.regulate this ,
wetland if cumulative wetland - acreage impacts for,the - ,entire project are.
t_ reater than l acre,- 'regardless of the size• of the iridividual 'wetland. For :-
hat reason, this wetland must -be characterized for purposes of COE permitting ` -
ssessment. ;
etland 3: DESCFIPTION r
etland 3 is about'90 feet by 70 feet in dimension, forming a flattened oval -.
long the north side of Discovery Road more than 200.feet -east of Rainier
f Road. Please refer to the attached map for clarification. It:is a Palustrine -
wxScrub -Shrub system that has formed as a result of Discovery Road -damming local'
stormwater runoff; there does not appear to be -any functional culvert.
v "Vegetation is primarily Spirea douglasii: (FACW) and young Al.nus: rubra (FAC) .
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The surface is mostly bare, indicating that water stands over the surface for
extended periods during the winter months. The soils are mapped as Clallamnotahydricsoil), but this area would be considered an inclusion. We..
assume that it would meet poorly drained or worse drainage class criteria
since there is evidence of long duration saturation within 3 inches of the
soil surface. The soil was observed to have 2 inches of organic deposit on.
the surface underlain by 3 inches of 10YR3 /2 coarse sandy loam with about 10%
gravel content. From 3 -9 inches., the soils are 10YR4 /1 coarse sandy loam with
a common medium distinct mottling pattern. Below 9 inches, the soil is
cemented, gleyed hardpan.
The area around and downstream of the culvert crossing 'at Rainier Road (also
mapped as Clallam) lacked hydric soil characteristics, and we purposely
sampled in an area that showed signs of having water standing on the surfaceduringthewinter, so should be the worst case example of drainage. The lack
of hydric characteristics indicates that while the area may flood from time totimeinresponsetostorms, the water does not stand long enough for the soilstodevelopanaerobicconditions. This area directly within the-drainage
corridor might be classified as somewhat poorly drained, but that is somewhat
questionable as it does not appear that the water table is enduring enough togreatlyimpactseasonalaccess.
The soils are coarse sandy loams with low gravel content, but colors were not
characteristic of a poorly drained condition. The surface was 10YR2 /2 (chromalessthan2, but value less than 4) to 14 inches. At 14 inches and extendingtogreaterthan18inches, the color changed abruptly to 10YR 4/3 (chroma
greater than 2) and the soils_ were cemented, although not as dense as those
observed within the wetland. There were no oxidized rhizospheres, "no
mottling, no unusually high organic matter contents within the top 20 inches.
In summary, although there is-a wetland associated with that drainage, it is
well outside the Rainier Street easement so will not be directly impacted byinstallationofthepipelinealongtheeasement.
Wetland 4; „ DESCRIPTION
Wetland 4 is about 20 feet by 360 feet in dimension, a linear feature as a
result of being formed in the base of a drainage. The drainage is directly
adjacent to a mini -mall parking lot, and as a result has been greatly impactedbypastdevelopment. Downstream areas behind the mall have been filled and
recontoured, possibly making the wetland smaller than it once was, but also
possibly obstructing drainage to some degree_ The drainage receives water
directly from Sims Way runoff and from a culvert under Sims that appears to
diagonal to the northeast. Please refer to the attached map for
clarification.
Wetland 4 is a Palustrine Scrub -Shrub system that has formed as a result of
collection of upstream runoff, probably becoming wetter over time as the
surrounding area developed. The wetland vegetation includes a wide variety ofspecies, including: Alnus Rubra (FAG), Sium suave (OBL), Equisetum telmateia
FACW), Typha latifolia (OBL), Rosa pisocarpa (FAG), Agrostis stolonifera
FACW), Gallium trifidum (FACU), Salix lasiandra (FACW +), Salix scouleriana
FAG), Ranunculus repens (ACW), Oenanthe sarmentosa (OBL), and Juncus effusus
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FACW). The surface' shows evidence "of recent standing water, although none
was observed on the day of the evaluation. -
The soils are mapped as Clallam.(not a hydric soil), but this drainage area " would be considered an inclusion. We assume that it would meet poorly drained
or worse drainage class criteria since there is evidence of long durationsaturationwithin11inchesofthesoilsurfaceandevidenceofregularfloodingonthesurface. The wetland soils at Flag 1 near Sines Way was
observed to have 10YR3 /2 loam and loamy sand from the surface to 11 inches,
underlain by 2.5Y5/2 distinctly mottled loamy sand soils to greater than 18inches. The directly adjacent upland soils had 10YR3 /3 loamy'sand soils to 8inchesunderlainby10YR5 /4 loamy sands to greater than 18 inches. These
soils meet the hydric soil criteria.
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In summary, the drainage is a jurisdictional wetland for COE purposes. As itisproposedtofillatleastpartofthedrainage, the impacted wetland area
would be included in the calculation for cumulative wetland acreage affectedbytheproject.
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