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Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Table of Contents List of Figures ............................................................................................................................ iii
1.0 Introduction .......................................................................................................................... 5
3.0 Wetland Delineation Methodology ...................................................................................... 5
4.0 Project Area Description ...................................................................................................... 7
4.1 Location ........................................................................................................................... 7
4.2 Climate ........................................................................................................................... 10
4.3 Geology and Geomorphology ........................................................................................ 11
4.4 Hydrology ...................................................................................................................... 18
4.5 Hydric Soils ................................................................................................................... 23
4.6 Vegetation ...................................................................................................................... 25
Vegetation Types .................................................................................................................. 27
5.0 Results ................................................................................................................................ 36
6.0 Wetland Conclusions ......................................................................................................... 42
7.0 References .......................................................................................................................... 48
Appendix I - 2007 Adamus/Bosworth Wetland Assessment .................................................... 49
Appendix II - WESPAK-SE for Switzer Creek 2011 .............................................................. 60
List of Tables
Table 1- Plant Species List ........................................................................................................... 34
Table 2 - Definitions for Wetland Indicator Codes ...................................................................... 34
Table 3 - Wetland Status and Classification for Project Area Sample Points. ............................. 36
List of Photographs
Photo 1 - West Spruce Trib Photo 2 - Cookie Trib .......................................... 19
Photo 3 - Jay Trib .......................................................................................................................... 19
Photo 4 - Wimpy Trib - ditched above DZ school........................................................................ 20
Photo 5 - Upper Crabapple Trib .................................................................................................... 20
Photo 6 - Lower Crabapple Trib ................................................................................................... 20
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 7 - Upper East Switzer Trib ................................................................................................ 21
Photo 8 - Lower Swampy Trib...................................................................................................... 21
Photo 9 - East Marriot Trib below sedge marsh in small bedrock canyon. .................................. 21
Photo 10 - Saturated, organic mucky peat of the Maybeso Series from a forested ...................... 23
Photo 11 - Saturated organic sedge peat of the Kina Series in a sedge marsh on the East Switzer
Trib. ............................................................................................................................................... 24
Photo 12 - Alluvial spruce forest understory. ............................................................................... 28
Photo 13 - Western hemlock /Sitka spruce forest in the upper west unit. ................................... 29
Photo 14 - Forested wetland in central western unit. .................................................................... 30
Photo 15- Poorly-drained dammed area along West Spruce Trib in the western unit, growing
back in red alder (Alnus rubra), horsetail (Equisetum) and Mertens sedge (Carex mertensii). ... 31
Photo 16 - Well-drained, dammed areas along Cookie Trib, in the western unit, growing back in
red alder with Sitka spruce (Picea sitchensis) and western hemlock (Tsuga heterophylla) in the
understory. .................................................................................................................................... 31
Photo 17 - A photo in the 1968 clear cut, on the hill between East Switzer Trib and West Switzer
Trib, growing back in Sitka spruce. .............................................................................................. 32
Photo 18 - 1943 clear cut, west of DZ school, coming back in Sitka spruce and western
hemlock. ........................................................................................................................................ 32
Photo 19 - Sedge marsh on East Switzer Trib. ............................................................................. 33
Photo 20 - Sedge marsh on West Switzer Trib ............................................................................. 33
List of Figures Figure 1 - Project area location. ...................................................................................................... 5
Figure 2 - Land ownership map for the Switzer Watershed. .......................................................... 8
Figure 3 - East unit of project area. The orange line shows the general project area, though for
wetland purposes there is an extension of the project area to the southwest to just beyond the
confluence of the east and west tributaries of Switzer Creek. This brings the total acreage for the
eastern unit to 88 acres. ................................................................................................................... 9
Figure 4 - The eastern unit of the project area as shown by the orange line and the 8 acre piece
just east of the school. ..................................................................................................................... 9
Figure 5 - 2011 Temperature data for Juneau Alaska (NOAA).................................................... 10
Figure 6 - 2011 precipitation totals for Juneau Alaska (NOAA). ................................................. 10
Figure 7 - Geology map of the Switzer Creek Watershed (USGS). ............................................. 11
Figure 8 - Surficial geology of the Switzer Creek Watershed (Miller 1975)( Carstensen 2008) . 12
Figure 9 - Surficial geology detail for the east Switzer Creek area (Carstensen 2008). ............... 16
Figure 10 - "A" lobe shows the project area former tidelands and present day, active tidelands
(Carstensen, 2008). ....................................................................................................................... 17
Figure 11- Map showing the relative position of the Switzer Creek Watershed in the larger
Juneau area (Carstensen 2008). ..................................................................................................... 18
Figure 12 - ADF&G and CBJ Anadramous water catalog mapping of the Switzer Creek area. .. 22
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Figure 13 - 1948 aerial photography of the project area. Trails, streams and roads not present
then are overlain. ........................................................................................................................... 26
Figure 14 - 1962 aerial photography annotated and overlain by project area trails and roads. .... 26
Figure 15 - 2006 CBJ aerial photography showing streams, trails and clearcut ages. ................. 27
Figure 16 - West Unit Wetland/Upland acreage amounts ........................................................... 42
Figure 17 - East Unit Wetland /Upland acreage amounts............................................................. 42
Figure 18 - Wetland delineation and Waters of the US map for the east unit. ............................. 43
Figure 19 - Sample point locations for the east unit. .................................................................... 44
Figure 20 - Sample point locations for the central unit. ............................................................... 45
Figure 21 - Wetland delineation and Waters of the US map for the west unit. ............................ 46
Figure 22 - Sample point locations for the west unit. ................................................................... 47
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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1.0 Introduction This document is a wetland report for City and Borough of Juneau, Lands Division to aid in land
inventory and development analysis for the Switzer Creek area. The project area includes 158
acres, with 70 acres in the west or DZ unit and 88 acres in the east unit.
Figure 1 - Project area location.
3.0 Wetland Delineation Methodology The project area was visited for delineation and mapping during the period from August 25
through September 1, 2011. Though this document will not be submitted to the US Army Corps
of Engineers as Jurisdictional Wetland Delineation document, the data gathered was done using
the US COE methodology.
The Army COE delineation methodology was used, as outlined in the 1987 Corps of Engineers
Wetland Delineation Manual - for Routine Determinations - greater than five acres, and amended
by the, Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Alaska
Region – November, 2007.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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A general reconnaissance of the site was accomplished from aerial photography, 10 foot contour
interval lidar, reports from previous wetland work done in the area and scoping work done by
Discovery Southeast naturalists and students. Transects, trending east-west and following trails
were done in some areas and intuitive controlled transects following natural, hydrology-
controlling landmarks, were walked across the three parts of the project area.
Representative sample points were done along the transects at any significant change in
vegetation, soils or hydrology. At each sampling point, the wetland status of that point was
determined by observing indicators of hydrophytic vegetation, hydric soil, and wetland
hydrology. Wetland and upland areas that were big enough to be mapped separately were
delineated using a Garmin Rino 530HCx GPS.
Vegetation was divided into three strata; tree, shrub and forb, and each layer was classified using
the prevalence index (a weighted-average wetland indicator status of all plant species in the
sample plot) and the dominance test (more than 50% of the dominant plant species across all
strata are rated obligate, facultative wet or facultative). Plant species were classified by the U.S.
Fish and Wildlife Service, and available on the “National List of Plant Species that Occur in
Wetlands.” The list was updated by the Army COE Alaska Plant Working Group, in Nov. 2009.
Hydrology was determined using two methods: (1) visually, if the water table is at or above the
surface, or (2) with a soil pit. The presence of standing water, depth to free water in the soil pit,
and depth to saturated soils were recorded. Other primary and secondary hydrology indicators
were recorded, such as presence of watermarks, sediment deposits, drift deposits, iron deposits,
hydrogen sulfide odor, geomorphic position, and drainage patterns in wetlands. Soil pits were
dug to a depth of 12-18 inches, or to bedrock refusal, to determine if indicators of hydric soils
were present. Soil colors were determined from a moist sample with the Munsell Soil Color
Chart.
Preliminary delineation mapping was accomplished by Bosworth Botanical Consulting and GIS
technician, Richard Carstensen of Discovery Southeast, using GPS data gathered in the field with
a Garmin Rino 530HCx (a WAAS-enabled, recreational grade GPS that works well under tree
canopy and has an advertised accuracy of 5-10 feet). The wetland boundaries were way-pointed
with the Garmin Rino
Polygon acreages and stream lengths were calculated in Arcmap.
Two different wetland classification systems were used to characterize the wetlands identified
with the project area:
1. The U.S. Fish and Wildlife Service wetland classification or what is often called the
Cowardin or NWI classification, is a commonly used system that, in freshwater
wetlands, is based on vegetative life form.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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2. The Canadian wetland classification system at the class level is hydrologic, based on the
overall genetic origin of the wetland ecosystem and the nature of the wetland
environment.
4.0 Project Area Description
4.1 Location
The project area is located along the west edge of the Lemon Creek Valley, 5.5 miles from
downtown Juneau and three miles from the Juneau International Airport. It has 2 distinct units:
the western or DZ school unit and the eastern unit. The easiest road access to the western unit is
via Old Glacier Highway to Renninger Drive up to Dzantik'i Heeni (DZ) School where trails
leave from the west edge of the parking lot or above the school and below the water tower. Road
access to the eastern unit is Old Glacier Highway to Lemon Creek Road to Mountain Ave. There
is a trail-head for the area trail system at the end of Mountain Drive.
The project area is all on City and Borough of Juneau (CBJ) property with US Forest Service
(USFS)owning the property uphill of CBJ and private ownership below (Figure 2).
The interpretive trail behind Dzantik’i Heeni Middle School (DZ) is among the 4 trail systems on
CBJ land that has been studied and described by Discovery Southeast (DSE) under Phase 1 of
their work for the City. The document assembled by Discovery Southeast (along with
collaborating DZ science students and teachers) for this trail system included natural and
cultural history information to be used in signage, and in interpretive booklets, brochures and
web products. Some of this information was used for this report (Carstensen 2008).
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Figure 2 - Land ownership map for the Switzer Watershed.
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Figure 3 - East unit of project area. The orange line shows the general project area, though for wetland purposes there is
an extension of the project area to the southwest to just beyond the confluence of the east and west tributaries of Switzer
Creek. This brings the total acreage for the eastern unit to 88 acres.
Figure 4 - The eastern unit of the project area as shown by the orange line and the 8 acre piece just east of the school.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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4.2 Climate
The Pacific Ocean and the coastal mountains strongly interact to influence climate patterns in
southeast Alaska. Frequent low-pressure systems from the Gulf of Alaska bring warm
temperatures and large storms into southeast Alaska where the high mountains of the Coast
Range block passage of these storms, generally resulting in heavy precipitation and high speed
winds in the region. Juneau has significant amounts of precipitation, in the form of both rain and
snow. Precipitation amounts and patterns are variable throughout CBJ depending on topography
and elevation. The closest NOAA weather station to the project area is at the airport and Figures
5&6 are 2011 climate data for the airport weather station.
Figure 5 - 2011 Temperature data for Juneau Alaska (NOAA).
Figure 6 - 2011 precipitation totals for Juneau Alaska (NOAA).
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4.3 Geology and Geomorphology
Most of the Switzer watershed, and all of the terrain underlying the west and the east project
areas, is in a belt of phyllite and slate. Most of this bedrock foundation is obscured by
surficial sediments (Figure 7). The strike of the bedrock units on Heintzleman Ridge trends
northwest-southeast, diagonally to the slope. This is reflected in numerous gullies and ravines
that control the direction of Switzer tributaries such as Spruce, Cookie, and West Switzer Trib. In
stream beds, slate and phyllite easily break down into flat, platy rocks that typically result in poor
habitat for aquatic invertebrates.
Figure 7 - Geology map of the Switzer Creek Watershed (USGS).
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Figure 8 - Surficial geology of the Switzer Creek Watershed (Miller 1975)( Carstensen 2008)
Ancient Landforms: To understand the configuration of surficial landforms at Lemon Creek, it’s important to
distinguish 2 major periods of glaciation: 1) the Great Ice Age (or Wisconsin Glaciation), which
peaked about 18,000 years before present (BP) and was ending around 9,000 BP, and; 2) the
Little Ice Age (or late Neoglacial), which peaked in the mid 1700s. On the map above (Figure 8),
older features associated with the ending of the Wisconsin period are shown in black, while more
recent Neoglacial features are shown in white. A thick blanket of marine fines was spread over
the coastal benches of Gastineau Channel and other low coastlines throughout Southeast.
Shortly after the ice went out, the channel was full of till-covered bergs, and as these melted they
dumped a load of coarse material–up to boulders in size–into the marine fines. Thus, the term
glaciomarine sediments. The northwest part of the project area passes through mapped
glaciomarine deposits. You can sometimes see sorted marine fines in the soils exposed where
tree roots are tipped up. The cleanest exposure of marine sediments near the DZ trail system is
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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in a recent slump on the west side of the V-notch gorge of Cookie Trib, on the way up to the
drained reservoir. As shown in the profile view on the surficial geology map, glaciomarine
deposits (green) are generally the thickest of the unconsolidated material covering bedrock in
Lemon Creek valley. Along transect A-B (Figure 8), marine features are overlain by colluvium
on their upper extent, and recent alluvial fan at their lower, seaward margin.
Ancient deltas Wherever streams entered Gastineau Channel in times of higher relative sea
level, deltas were deposited; today these marine features are high and dry. Rich in gravel from
bedload brought down by the streams, the raised marine deltas of Lemon Creek valley served as
Juneau’s primary source of construction fill for many decades. The recently grassed-over slope
behind Home Depot is all that remains of the thick layer of deltaic sediments once covering the
entire Commercial Boulevard district to a depth of perhaps 30 feet above the current surface.
With the eventual exhaustion of these deposits, quarries have had to shift to more expensive
shot-rock operations on Secon land farther up the valley. The closest to the west project area, of
the ancient delta deposits (dark brown) mapped by R.D. Miller is a quarter mile east of the DZ,
underlying the 1943 clear-cut on the Marriott Trail (Figure 13). Deltas, once raised to supratidal
elevations, are similar in form and sediment composition to alluvial fans, described below.
Sorted, fairly coarse and well-drained material provides an optimum rooting environment for
large trees. Stump size in the 1943 clear-cut, however, is unremarkable, and examination of the
1929 air photos suggests this stand was not as tall as the forest on the Switzer Village fan. It’s
not clear why this delta forest was targeted so early. But long before the 1943 clear-cut on the
Marriott Loop, truly giant spruces on ancient deltas were selectively logged by handsaw in the
area south of today’s Home Depot
Colluvium Miller distinguishes many types of surficial deposits resulting from gravity
movement down steep slopes. “Colluvium” is the most stabilized of these deposits, and
presumably the oldest. Less stable slopes are mapped as varieties of “talus” and “debris flow.”
For millennia after the Great Ice Age, steep mountainsides–at first unforested–were subject to
massive downslope movements, both imperceptible and sudden. Gradually, the roots of conifers
anchored the moving material on steep slopes, and podzol soils developed over millennia on the
conifer forest floor. There’s actually quite a bit of unmapped stabilized colluvium upslope from
the band shown in lavender on the surficial geology map (Figure 8). Colluvium can be a good
substrate for growth of large trees, particularly when parent material (in this case slate and
phyllite) is conducive, but they tend to be more widely scattered than on alluvium.
Intermediate-aged landforms:
Alluvial terrace Several millennia after the Great Ice Ages ended, sea level regained equilibrium
somewhere close to its present elevation. But mountain slopes in the Lemon headwaters
remained raw and active, continuing to send large quantities of sediment downstream. This
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slowly built a broad alluvial flood plain outward from the toe of the ancient raised delta
formations just above the Lemon Creek estuary. These alluvial terraces are shown in light brown
on the surficial geology map (Figure 8). They’re separated from active alluvium by their higher
elevation. As headwaters stabilized and Lemon Creek carried less material, it sliced downward
through its terrace deposits, leaving them inactive. Today, these terraces occupy the belt between
about 30 and 40 feet above Mean Lower Low Water (zero feet sea level). Very little of this old
alluvial terrace belt remains undeveloped. Pre-logging air photos suggest fairly large old-growth
trees and good drainage. Flat, well-drained surfaces are hard to come by in steep, wet country
like Southeast; after the forests were felled and stumps pulled, the belt was mostly converted to
residential and industrial development.
Recent landforms:
The second period of glaciation–the Little Ice Age–was much less severe than the Wisconsin
episode. Instead of a mile-thick glacier covering all but Juneau’s highest peaks, the toes of our
valley glaciers expanded by a few miles in the mid-1700s AD, and thickness of the Juneau
Icefield increased by about 500 feet. But the Little Ice Age strongly modified our coastal
landforms and habitats. Whereas post-Wisconsin isostatic land adjustment was measured in
hundreds of feet, post Little Ice Age depression and subsequent recovery affected only the zone
between today’s 20 and 30-foot elevations. In gently sloping estuaries like Lemon Creek, that
10-foot elevational belt occupies a lot of acreage. In addition to sea-level changes, greater snow
accumulations in the mountain highlands increased stream flow and sediment transport. Glaciers
expanded on the margins of Juneau Icefield. Degrading streams once again became aggrading
systems, adding new layers to fans and flood plains.
Alluvial fan These landforms occur where steep hillside streams encounter gentle lowland
gradients, dumping sediment and over millennia creating fan-shaped landforms. Southeast’s
alluvial fans are thousands of years old. But in northern Southeast where the Little Ice Age was
strongest, some fans became so active that few trees appear to be older than 250 or 300 years.
DZ Middle School sits on a 100-acre alluvial fan built up from the deposits of Cookie, Spruce
and Wimpy Tribs. Although trees here were not especially old compared to those on more
stabilized upland slopes, they were exceptionally vigorous. Some of the tallest spruces in Lemon
Creek Valley grew on the fan southwest of Dzantik’i Heeni, where Switzer Village now lies. We
saw in the preceding bedrock description how alluvial fans–especially those with a substantial
phyllite/slate component–hosted the earliest clearcut logging in the Juneau area. Juneau
hydrologist Dan Bishop said that after the logging of Switzer fan, the overburden was pushed
across Glacier Highway to become the pad under today’s Walmart parking lot.
Active alluvium At the time of first European settlement in this valley, the glacial Lemon Creek
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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was still an aggrading system; active alluvium spread throughout the lower valley and built a
lobe out into the upper estuary that shows well on 1948 and 1962 air photos. Valley flood plains,
like alluvial fans, are slightly domed in the center and lower in the margins. This is imperceptible
to the human eye, but when valley centers are slightly higher than their margins, tributary
streams coming off valley walls are often shunted along the sides of the valley for some distance,
even reaching the sea before they can manage to link up to the primary stream or river. Such
valley-margin creeks are called yazoo streams; the 1948 and 1962 pre-development air photos
show the dominance of Lemon over Switzer Creek particularly well. As glaciers receded, Lemon
Creek’s load decreased, and it began to down-cut, just as it did after formation of the older
alluvial terraces described above. This, combined with gradual development right up to the
stream edge, has boxed it in so that the zone of active alluvium is now narrower than the yellow
strip mapped by Miller in 1975. Farther upstream on private lands, gravel mining often sends
heavy slugs of fresh sediment down into the estuary. Lemon Creek seems to be considered
Juneau’s “sacrificial stream” for construction material, perhaps a logical choice given the
alternatives.
Recent landslide Miller mapped a large landslide on East Switzer trib. Evidently he felt that this
huge lobe of debris came down off Heinztleman Ridge and deflected southwestward, covering
the logged off hilltop through which the Dick Marriott trail now loops. His map also shows an
escarpment at the 2500 foot elevation in the zone of exposed schist; possibly he felt this was one
of the originating points for the slide. CBJ’s lidar-generated 10-foot contours, indicates it
unlikely that the entire 140-foot Marriott Hill could be composed of landslide debris at so distant
a location from the hill slope that spawned it. Probably Miller concluded that the recent slide
deposits spread a “blanket” over ancient deltaic material, contiguous with that of the deltaic hill
above the prison. He cored trees on the deposit and got one germination age of ~1460 AD,
determining that the landslide must have occurred “pre 1500.” Where the mounded landslide
debris blocks and turns West Switzer to the southwest, there’s a marsh wetland (Figure 9). There
is also a large marsh wetland on the East Switzer Trib. on the east side of the landslide hill.
Relatively warm groundwater, stored in this deposit and slowly released, helps to account for the
high fish values of Switzer Creek.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Figure 9 - Surficial geology detail for the east Switzer Creek area (Carstensen 2008).
Emergent tidelands With decreased glacial pressure from the thinning Juneau Ice field, the
land today is rising at about 0.6 inches per year in the Lemon Creek watershed, creating a belt of
raised former tideland. Today, an extremely high tide laps against the base of the Walmart pad
and backs up Switzer Creek all the way to its Glacier Avenue culvert and above. But during the
peak of the Little Ice Age in the mid 1700s, high tides reached farther, filling the Davis
Meadows almost all the way to Marriott Pond (Figure 10). (Of course, at that time they were not
meadows but tidal salt marsh.)
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Figure 10 - "A" lobe shows the project area former tidelands and present day, active tidelands (Carstensen, 2008).
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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4.4 Hydrology
Figure 11- Map showing the relative position of the Switzer Creek Watershed in the larger Juneau area (Carstensen
2008).
All of the perennial and intermittent streams of the project area flow into Switzer Creek, which
flows into the Mendenhall Wetlands Wildlife Refuge and Gastineau Channel just east of Sunny
Point and west of Lemon Creek. The headwaters of the Switzer Creek watershed are fed by the
steep, southeast facing slope of Heinztleman Ridge. Most of the tributaries of Switzer Creek
were mapped by various agencies including: the USFS (included in the USFS - Tongass GIS
streams layer) and the Alaska Department of Fish and Game (ADF&G) in their anadramous
streams catalog. Work done in the 2000's by DZ students in conjunction with Discovery
Southeast naturalist Richard Carstensen included studying, mapping and in some cases naming
some of the tributaries of Switzer Creek that are within this project area. Those tributaries
include: Spruce Trib, Cookie Trib, Wimpy Trib, and Robins Trib. Three, so far unmapped and
unnamed, tributaries were mapped and named for this report: Jay Trib, Crabapple Trib and
Swampy Trib (Figures 17 & 18) (Photos 1-9). There is a pond at the confluence of the East and
West Switzer Tribs (or sometimes called the Marriott Tribs) called Marriott Pond.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 1 - West Spruce Trib Photo 2 - Cookie Trib
Photo 3 - Jay Trib
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 4 - Wimpy Trib - ditched above DZ school
Photo 5 - Upper Crabapple Trib
Photo 6 - Lower Crabapple Trib
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Photo 7 - Upper East Switzer Trib
Photo 8 - Lower Swampy Trib
Photo 9 - East Switzer Trib below sedge marsh in small bedrock canyon.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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The tributaries flowing through the project area are mostly medium gradient streams with cobble
substrate, though the lower reaches of the East and West Switzer Tribs, in the eastern part of the
project area, are lower gradient, slightly- meandering streams with some finer gravel and
substrate that is good for salmon spawning. Figure 12 shows the ADF&G and the CBJ mapping
of the anadramous streams of the Switzer Creek area. The lower reaches of Spruce Trib, Wimpy
Trib, Robins Trib, Crabapple Trib, Marriott Pond, East Switzer Trib and West Switzer Trib are
spawning, overwintering and rearing reaches for chum, pink, coho and a few scattered sockeye
salmon, Dolly Varden and cutthroat trout .
Figure 12 - ADF&G and CBJ Anadramous water catalog mapping of the Switzer Creek area.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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4.5 Hydric Soils
The project area hydric soils vary according to the geomorphic and hydrologic catena, from the
shallow-to-bedrock soils of the steeper hillsides to the organic, saturated, soils in the relatively
flat and poorly drained parts of the project area. The system of soil classification used by the
National Cooperative Soil Survey has six categories (USDA, 1999). Beginning with the
broadest, these categories are: order, suborder, great group, subgroup, family, and series. The
series level is the most detailed category. In this report soils are discussed to the series level
when classified to that level.
The soils of the west unit of the project area are mostly mucky peats of the Maybeso Series and
poorly drained mineral soils of the Wadleigh Series (Schoephorster 1974). During the time of
visit the soils were saturated throughout all of the wetland (except on scattered hummocks). The
soils of the wetland on the old dam site along East Spruce Trib are new soils that have yet to
develop many of the characters of hydric soils since the water was drained from the reservoir but
there is a layer of silt laid down when the reservoir was full, that impedes drainage and is gleyed.
The Wadleigh series are poorly drained shallow soils over para-lithic compact till or uplifted
glaciomarine sediments. Slopes range from 5 to 75 percent. The overstory vegetation is
mainly western hemlock with some Sitka spruce. The understory vegetation is dominantly
blueberry, rusty menziesia and skunk cabbage.
The Maybeso Series consists of deep, very poorly drained soils formed from decomposing
organic matter which overlies glacial till or uplifted glaciomarine sediments. These soils
occur on broad ridge tops, mountainsides, and valley side slopes with western hemlock,
blueberry and skunk cabbage. Slopes range from 5 to 60 percent (Photo 10)
Photo 10 - Saturated, organic mucky peat of the Maybeso Series from a forested
wetland in the western unit of the project area.
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The soils of the eastern unit of the project area are more varied. The lowlands areas along
Switzer Creek below and above Marriott Pond and in sedge marshes on the upper parts of East
and West Switzer Tribs have hydric organic soils of the Kina Series and mucky peats of the
Maybeso Series and Wadleigh Series.
The Kina series consists of very deep, very poorly drained soils that formed in partially
decomposed organic material derived from sedges. Kina soils occupy depressional bench-
like areas associated with the toe-slope, lower back-slopes, and floors of valleys. Slopes
range from 0 to 60 percent. The vegetation is dominantly sedges, mosses, and plants of the
Ericaceae family (Photo 11).
Photo 11 - Saturated organic sedge peat of the Kina Series in a sedge marsh on the East Switzer Trib.
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4.6 Vegetation
The project area vegetation patterns correspond to the geologic, geomorphic, hydrologic and
soils patterns of the overall area. The steeper, well-drained slopes of the deltaic and alluvial fan
areas are mostly upland vegetation. The flatter basin areas, toe of slope discharge areas and areas
underlain by uplifted glaciomarine silts have wetland vegetation of various types.
Project Area Wetland Classification (Canadian Wetland Classification and Cowardin
Classification)
Forested Wetland (PFO4) - The forested wetlands in Southeast Alaska are almost always
oligotrophic wetlands with western hemlock trees dominating. They are usually found in
shallowly sloping lowland areas with poorly-draining glacial till or glaciomarine
sediments underlying shallow (1.5-3 feet) mucky peats.
Sedge Fen or Marsh (PEM1/PSS1/PFO4) - A fen or marsh is a peat landform where the
rooting zone has ground water or surface water flowing through it. These waters are rich
in dissolved minerals and are minerotrophic. Marshes in the project area are dominated
by Sphagnum moss, sedges and bulrush. Fens are often found at the toe-of-slope where
ground water flowing downslope is forced to the surface by impermeable layers. They are
also found as a transition zone between upland areas and bogs.
The following aerial photo sequence, from Richard Carstensen's 2008 DZ scoping document,
1948 - 1962 - 2006, shows the change in vegetation due to clear cuts, road and building
construction, dam building and dam deconstruction, isostatic rebound, and plant succession.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
26
Figure 13 - 1948 aerial photography of the project area. Trails, streams and roads not present then are overlain.
Clear cut ages included.
Figure 14 - 1962 aerial photography annotated and overlain by project area trails and roads.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
27
Figure 15 - 2006 CBJ aerial photography showing streams, trails and clearcut ages.
Vegetation Types The vegetation of the project areas is a mixture of old growth forest, second growth forest and
several small areas of sedge marsh.
Old-Growth Forests Three basic kinds of old-growth forest can be found within the project area and though each type
contains trees many centuries old, and qualifies as old growth, structurally they are very
different.
1) Alluvial Sitka spruce/devils club/skunk cabbage forest, as is found in the lowland alluvial
reaches of East and West Switzer Tribs and some small patches in the lower reaches of Spruce
Trib. (in some well drained areas as in the upper part of West Switzer Trib this forest is well
drained and the skunk cabbage drops out).
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 12 - Alluvial spruce forest understory.
2) Productive upland western hemlock/Sitka spruce/blueberry forest as is found in the northern
part of the west unit (north of the trail above DZ school) this line corresponds with the boundary
between the well drained colluvial material and the poorly drained material over uplifted
glaciomarine sediments. Much of the upland forest between DZ and forest limit at roughly 2000
feet is majestic, with large old-growth hemlocks and scattered spruces 4 or more feet in diameter.
At the toe of the long upland slope above the school, the surface grades to gentler fan and flood
plain deposits. Much of this forest has been clear cut, and all was selectively logged in the early
1900s. In spite of this, the spruce dominated forest along Switzer Creek has large trees, many of
them once rejected by the loggers, but now “released” and fast growing because of the increased
light.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 13 - Western hemlock /Sitka spruce forest in the upper west unit.
3) Not all of the project area forests are productive. And given the history of forest high-grading,
much of what remains is wet and of little interest to either loggers or land developers.
DZ school itself was constructed upon forested wetland, requiring special exemptions in the
building permit. Scrubby forested wetland as is found along the upper part of the East Switzer
Trib, the forest just above DZ, and a forested wetland at the far west edge of the western unit of
the project area.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 14 - Forested wetland in central western unit.
Second-Growth Forests There are two disturbed areas within the project area that were clear cut at different times and
the whole project area was selectively logged in the early 1900s. Dams for water storage, were
placed on Cookie Trib and West Spruce Trib. The dams were removed in 1986.
The clear cuts are re-growing with a Sitka spruce and western hemlock overstory and little to no
understory. The previously dammed and submerged areas are re-growing with red alder. One of
the dam sites has Cookie Trib flowing through it and draining it, so the understory consists
mostly of spruce and hemlock seedlings. Most of the other dam site is offset from West Spruce
Trib and retains its layer of silt. The silt layer perches the water table, making the area wet and
giving it an early successional understory of horsetail and Merten's sedge (Carex mertensii).
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 15- Poorly-drained dammed area along West Spruce Trib in the western unit, growing back in red alder (Alnus
rubra), horsetail (Equisetum) and Mertens sedge (Carex mertensii).
(Photo series by Richard Carstensen)
Photo 16 - Well-drained, dammed areas along Cookie Trib, in the western unit, growing back in red alder with Sitka
spruce (Picea sitchensis) and western hemlock (Tsuga heterophylla) in the understory.
1986
1986
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 17 - A photo in the 1968 clear cut, on the hill between East Switzer Trib and West Switzer Trib, growing back in
Sitka spruce.
Photo 18 - 1943 clear cut, west of DZ school, coming back in Sitka spruce and western hemlock.
Sedge Marsh Communities Along the upper parts of East and West Switzer Tribs are two large sedge marshes. The one
along East Switzer Trib grades into forested wetland both up and downstream (Figures 9 and 17).
The marsh is dominated by Sitka sedge (Carex sitchensis) but also has smaller amounts of bull
rush (Scirpus microcarpus) and skunk cabbage (Lysichiton americanum).
1968
1943
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Photo 19 - Sedge marsh on East Switzer Trib.
Photo 20 - Sedge marsh on West Switzer Trib
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Table 1- Plant Species List
Scientific name Common name Indicator status1
Alnus rubra red alder FAC
Alnus sinuata Sitka alder FAC
Athyrium felix-femina lady fern FAC
Blechnum spicant deer fern FAC
Calamagrostis canadensis bluejoint FAC
Cinna latifolia wood reedgrass OBL
Carex mertensii Mertens sedge FACW
Carex sitchensis Sitka sedge OBL
Circium alpinum enchanters nightshade FACW
Coptis asplenifolius goldthread FAC
Coptis trifoliata goldthread FAC
Cornus canadensis dwarf dogwood FACU
Equisetum arvense horsetail FACU
Equisetum fluviatile water horsetail OBL
Equisetum variegatum variegated horsetail FACW
Gymnocarpium dryopteris oak fern FACU
Lysichiton americanum skunk cabbage OBL
Maianthemum dilatatum deer berry NI
Menyanthes trifoliatum buck bean OBL
Menzisia ferruginea false azalea NI
Malus fusca crabapple FACU
Oplopanax horridum devils club FACU
Picea sitchensis Sitka spruce FACU
Rubus pedatus trailing raspberry FAC
Rubus spectabilis salmonberry FACU
Salix sitchensis Sitka willow FAC
Sambucus racemosa elderberry FACU
Scirpus microcarpus small-fruited bulrush OBL
Sorbus sitchensis mountain ash FACU
Streptopus amplexifolius twisted stalk FAC
Taraxacum officinale dandelion FACU
Tiarella trifoliata foamflower FAC
Tsuga heterophylla western hemlock FAC
Vaccinium alaskaense Alaskan blueberry FAC
Vaccinium ovalifolium early blueberry FAC
Vaccinium parvifolium Red huckleberry NI
Viola glabella yellow violet FACW
Table 2 - Definitions for Wetland Indicator Codes
Indicator
Code
Wetland
Type
Comment
OBL Obligate Occurs almost always (estimated probability 99%) under natural conditions in
1 See Table 2 for abbreviation definitions
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Wetland wetlands.
FACW Facultative
Wetland
Usually occurs in wetlands (estimated probability 67%-99%), but occasionally found in
non-wetlands.
FAC Facultative Equally likely to occur in wetlands or non-wetlands (estimated probability 34%-66%).
FACU Facultative
Upland
Usually occurs in non-wetlands (estimated probability 67%-99%), but occasionally
found on wetlands (estimated probability 1%-33%).
UPL Obligate
Upland
Occurs in wetlands in another region, but occurs almost always (estimated probability
99%) under natural conditions in non-wetlands in the regions specified. If a species
does not occur in wetlands in any region, it is not on the National List.
NI No indicator Insufficient information was available to determine an indicator status.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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5.0 Results
Twenty-three out of 65 of the sites sampled were in wetlands, 24 of 65 were waters of the US, 6
were wetland/upland boundaries and 12 were upland (Table 1). Wetland boundaries were drawn
using the results of the field sampling and GPS tracks and waypoints.
Table 3 - Wetland Status and Classification for Project Area Sample Points.
Sample pts.
and WOUS
Dominant vegetation/
hydrology /
geomorphology
Wetland status - NWI class
West DZ Area Sample Pts.
1 Stream crossing Waters Of The US
2 Intermittent drainage Wetland PEMI/PFO4/Waters Of
The US
3 Stream crossing Waters Of The US
4 W. hemlock /skunk cabbage/enchanters
nightshade - Swale with intermittent
drainage
Wetland - PFO4
5 Trail edge - fill Upland
6 Sitka spruce/lady fern/oak fern - old clearcut Upland
7 W. hemlock /skunk cabbage, hillside swale Wetland - PFO4
8 Small intermittent stream - culvert under trail Waters Of The US
9 Small intermittent stream Waters Of The US
10 W. Hemlock/ devils club/elderberry -
gently-sloping hillside
Wetland – PFO4
11 Small intermittent stream - culvert under trail
- same stream as #9
Waters Of The US
12 Large stream (Cookie Trib. - 6-8 ft. wide 5-
10 inches deep)
Waters Of The US
13 Medium stream (3-4 ft. wide 3-8 inches
deep)
Waters Of The US
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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14 W. Hemlock/early blueberry/ false azalea/
hillside
Wetland - PFO4
15 Swale with skunk cabbage Wetland - PEM1/ Waters of the
US
16 Swale with skunk cabbage Wetland - PEM1/ Waters of the
US
17 Swale with devils club Wetland - PEM1/ Waters of the
US
18 Small intermittent stream Waters of the US
19 Two small intermittent streams Waters of the US
20 Small intermittent stream Waters of the US
21 Small intermittent stream Waters of the US
22 Continuation of #21 small intermittent
stream
Waters of the US
23 Confluence of #13 and #22 Waters of the US
24 Small intermittent stream Waters of the US
25 Small intermittent stream Waters of the US
26 Wetland boundary Wetland/Upland boundary
27 Medium stream - continuation of #13 Waters of the US
28 Cookie Trib Waters of the US
29 Small seep along the Cookie Trib trail Wetland – PFO4
30 W. hemlock/false azalea/early blueberry/ Upland
31 Small intermittent stream Waters of the US
32 Med. stream confluence Waters of the US
33 Trail crosses #32 Waters of the US
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34 Trail intersection
35 Doghair Sitka spruce/W. hemlock/ red alder/
few skunk cabbage disturbed
Upland
36 Confluence of W. Spruce Trib and #4 Waters of the US
37 Small skunk cabbage swale - intermittent
drainage
Waters of the US/Wetland PFO4
38 Small skunk cabbage swale - intermittent
drainage
Wetland – PFO4
39 Top of w. hemlock/blueberry/skunk cabbage Wetland – PFO4
40 Red alder/Mertens sedge/creeping buttercup Wetland – PFO4
41 W. hemlock/ skunk cabbage/
salmonberry/lady fern hillside
Wetland – PFO4
42 Small stream comes out of culvert here Waters of the US
43 Between 42 & 43 is a deep ditch Waters of the US
44 Devils club/ skunk cabbage/salmonberry Wetland – PSS1
45 Yellow cedar Wetland – PFO4
46 Med. stream Waters of the US
47 Devils club/ red elderberry/lady fern Wetland – PSS1
48 Small intermittent stream Waters of the US
49 Small intermittent stream Waters of the US
50 East Spruce Trib. Waters of the US
51 Sitka spruce/w. hemlock/red alder/
salmonberry/ blueberry/devils club/wood
fern
Upland
Central DZ area sample points
52 Small perennial stream in upland forest Waters of the US/ Upland
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53 Boundary Wetland/Upland boundary
54 Skunk cabbage/Sitka willow/crabapple Wetland - PSS1
55 Stream Waters of the US
56 Small stream confluence Waters of the US
57 Boundary/small stream crossing Wetland/Upland boundary/
Waters of the US
East DZ area sample points
58 Sitka spruce/W. hemlock/spiny wood fern Upland
59 W. hemlock/skunk cabbage/lady fern Wetland – PFO4
60 Red alder/skunk cabbage/enchanters
nightshade/ lady fern
Wetland – PFO4
61 Sitka spruce/ skunk cabbage Wetland - PFO4/Waters of the
US
62 Sitka willow/sedge/ skunk cabbage Wetland - PSS1
63 Wetland boundary at toe of slope Wetland/Upland boundary
64 Small stream Waters of the US
65 Small stream Waters of the US
66 Small stream Waters of the US
67 Small stream Waters of the US
68 Small stream Waters of the US
69 Pipeline Cord road
70 Big stream Waters of the US
71 Small stream/ red alder/devils club/lady fern Wetland - PFO2/ Waters of the
US
72 Large stream Waters of the US
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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73 Sedge marsh Wetland PEM1
74 Small stream coming off steep hillside Waters of the US
75 Small hill upland/wet boundary Boundary
76 Swampy Trib goes through bedrock gorge Waters of the US
77 Wetland on East side and upland on west Boundary
78 Swampy Trib bridge Waters of the US
79 SW edge of sedge marsh Wetland - PEM1
80 Cross E. Switzer Trib Waters of the US
81 Wetland boundary Wetland/Upland boundary
82 Wetland boundary Wetland/Upland boundary
83 Wetland along trail Wetland - PFO4
84 Wetland Wetland - PEM1
85 Small stream just above sedge marsh Waters of the US
86 Wetland boundary Wetland/Upland boundary
Central DZ area sample points
87 Wetland boundary Wetland/Upland boundary
88 Small stream crossing Waters of the US
89 Wetland boundary Wetland/Upland boundary
90 Sedge marsh along stream beginning Wetland - PEM1/Waters of the
US
91 Stream goes underground Waters of the US
92 Wetland boundary Wetland/Upland boundary
East DZ area sample points
93 Confluence Waters of the US
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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94 Intermittent stream Waters of the US
95 Confluence Waters of the US
96 Tiny stream Waters of the US
97 Upland Upland
98 End of stream Waters of the US
99 Tiny stream Waters of the US
100 Confluence with Switzer Creek Waters of the US
101 Small stream in swampy area Waters of the US/Wetland -
PEM1
102 SE edge of sedge marsh Boundary - PEM1
103 Large stream Waters of the US
104 Small stream Waters of the US
105 Stream comes into sedge marsh Waters of the US/Wetland -
PEM1
106 Stream comes into sedge marsh Waters of the US/Wetland -
PEM1
107 Large stream on w. edge of sedge marsh Waters of the US/Wetland -
PEM1
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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6.0 Wetland Conclusions
The western unit of the project is 78 acres total, 15.8 acres of the total were found to be wetland.
The eastern unit of the project is 88 acres total, 36.1 acres of the total were found to be wetland.
The total length of the waters of the US (rivers, perennial streams, intermittent streams and
ditches) for the western unit of the project is 7,838 feet.
The total length of the waters of the US (rivers, perennial streams, intermittent streams, and
ditches) for the eastern unit of the project is 9,335 feet.
Figure 16 - West Unit Wetland/Upland acreage amounts
Figure 17 - East Unit Wetland /Upland acreage amounts
15.8
54.2
0
10
20
30
40
50
60
Wetland Upland
Acres
West Project Unit - Wetland /Upland
Acreage Amounts
36.1
51.9
0
10
20
30
40
50
60
Wetland Upland
Acres
East Project Unit - Wetland /Upland
Acreage Amounts
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
43
Figure 18 - Wetland delineation and Waters of the US map for the East Unit.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Figure 19 - Sample point locations for the east unit.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Figure 20 - Sample point locations for the central unit.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Figure 21 - Wetland delineation and Waters of the US map for the West Unit.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Figure 22 - Sample point locations for the western unit.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
48
7.0 References Bosworth, Koren and Paul Adamus Ph. D. January 2007. Delineation and Function Rating of
Jurisdictional Wetlands on Potentially Developable City-owned Parcels In Juneau, Alaska. CBJ
Community Development.
Carstensen, Richard - Discovery Southeast. April, 2008. Draft - Dzantik’i Heeni Nature Trails
Scoping for Interpretive Signage and Publications. For CBJ - Parks and Recreation.
Cooperative Soil Survey. 2010. Alaska Soil Series Data.
http://soilsurveydemo.org/soilseries.asp?x=A&sort=Series&st=AK
Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of Wetlands and
Deepwater Habitats of the United States. Office of Biological Services, USDI Fish and Wildlife
Service. Washington, D.C. FES/OBS-79-31. 131pp.
D'Amore, David V. 2010. personal communication. Wetland Soils of Northern Southeast Alaska.
D'Amore, David V., Warren C Lynn,. 2002. Classification of Forested Histosols in Southeast
Alaska. Soil Sci. Soc. Am. J. 2002 66: 554–562
Hulten, E. 1968. Flora of Alaska and Neighboring Territories. Stanford University Press, Stanford,
California. 1008 pp.
Miller, R. 1975. Surficial geology map of the Juneau urban area and vicinity, Alaska. Miscellaneous
Investigations Series I-885.
National Wetlands Working Group/ edited by: B.G. Warner and C.D.A. Rubec, 1997. The Canadian
Wetland Classification System, Second Edition. Wetland Research Centre, University of Waterloo,
Waterloo, Ontario.
Reed Jr., Porter B., 1988. National List of Plant Species That Occur in Wetlands: Alaska (Region A).
U.S.D.I, Fish and Wildlife Service, Research and Development, Washington, DC. 79 pp.
Schoephorester, Dale B. and Clarence E. Furbush. June 1974. Soils of the Juneau Area, Alaska
U.S. Army Corps of Engineers, U.S. Army Corp of Engineers Wetlands Delineation Manual, USDA
Soil Conservation Service (NRCS).
Technical Report Y-87-1, Environmental Laboratory. U.S. Army Engineer Waterways Experiment
Station, Vicksburg, MS.
U.S. Army Corps of Engineers. 1987. Corps of Engineers Wetland Delineation Manual.
Technical Report Y-87-1, US Army Waterways Experiment Station, Vicksburg, MS.
US Army Corps of Engineers, Oct. 2007. Regional Supplement to the Corps of Engineers Wetland
Delineation Manual: Alaska Region, Environmental Laboratory, ERDC/EL TR-06-x, US Army
Engineer Research and Development Center, Vicksburg, MS.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Appendix I - 2007 Adamus/Bosworth Wetland Assessment
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Scores for 12 functions in parcel unit 1 wetlands, and resulting management
category based on formulas described in CDD (1997).
Scores: 7= very high, 6= high, 5= moderate high, 4= moderate, 3= moderate low, 2= low, 1= very low. Not all
functions can have the full range of scores (1 to 7).
Pa
rcel u
nit
Wetla
nd
Gro
un
d w
ater
Disch
arg
e
Sed
imen
t/ To
xica
nt
Reten
tion
Nu
trient E
xp
ort
Rip
aria
n S
up
po
rt
Sa
lmo
nid
Ha
bita
t
Ero
sion
Sen
si- tivity
Gro
un
d w
ater
Rec
ha
rge
Hy
dro
- log
ic Co
ntr
ol
Deten
tion
Va
lue
Recre
a- tio
n P
oten
tial
Recre
a- tio
n A
ctu
al
Wild
life H
ab
itat
Ma
ng
e- m
ent C
ateg
ory
1 28 6 6 6 5 6 2 2 5 4 6 3 6 B
1 30 2 6 4 3 1 2 6 6 4 6 6 5 B
1 31 6 6 4 6 1 2 4 6 4 6 6 5 B
1 48 6 6 4 5 3 2 4 5 4 3 3 3 C
1 49 6 6 4 5 3 2 4 5 4 3 3 3 C
Wetland #30 - This wetland is just west of the DZ school. It was assigned to category B due
partly to relatively high ratings for Groundwater Recharge, Sediment/Toxicant Retention,
Hydrologic Control, and Recreational Use (Table 2). Fish cannot access any part of this wetland.
This wetland was not assigned to category A partly because of its relatively high PP (lower
public preference) and PA (more numerous practicable alternatives) scores based on 1987
information for the closest wetland (L15) assessed at that time. The wetland is mostly forested
with stunted spruce and hemlock, with a small open bog in its southern portion. The soil has
been mapped as a hydric soil of the Wadleigh Series, and during the time of visit was saturated
throughout all of the wetland (except on scattered hummocks).
Wetland #31 - This wetland is west of the DZ school and west of wetland #30. It was assigned
to category B based partly on relatively high ratings for Groundwater Discharge,
Sediment/Toxicant Retention, Riparian Support, Hydrologic Control, and Recreational Use
(Table 2). Fish cannot access any part of this wetland, but East Creek flows along the western
edge. This wetland was not assigned to category A partly because of its relatively high PP
(lower public preference) and PA (more numerous practicable alternatives) scores based on 1987
information for the closest wetland (L15) assessed at that time. This wetland site was formerly a
pond created by a small catchment dam on East Creek. The water table is perched in the wetland
area by the bedrock that outcrops there. The wetland has an unusual gramimoid understory with
a somewhat open overstory of red alder and Sitka willow. Young fast-growing spruce saplings
are coming up under the red alder overstory. The soil was a saturated, gleyed soil.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Wetland #49 - This small sedge marsh is upstream from wetland #28, and is intercepted by an
ephemeral tributary to Switzer Creek. It was assigned to category C based partly on a relatively
low rating for Erosion Sensitivity and moderate ratings for Salmonid Habitat, Recreational use,
and Wildlife Habitat (Table 2). A few of the characteristics that contributed to the low ratings
for these functions include its relatively flat slope and lack of structurally diverse vegetation.
This wetland was not assigned to category B partly because of its relatively high PP (lower
public preference) and PA (more numerous practicable alternatives) scores based on 1987
information for the closest wetland (L15) assessed at that time. The wetland is dominated by
Sitka sedge and skunk cabbage. The water table over most of the wetland at the time of the visit
was 9-10 inches above the surface (i.e, the wetland was flooded) and the soil was a sedge peat of
the Kina Series.
This wetland is the same as the isolated wetland delineated along the NW edge of the east
project area in the 2011 delineation. This area was also included in the wetland assessment done
in Sept. of 2011 using the new wetland assessment methodology developed by Paul Adamus.See
Appendix II.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Wetland #48 - This wetland was across a low divide from wetland #49 and is identical to it
with regard to all its functional ratings and hydrologic regime. It also was flooded by an
ephemeral tributary of Switzer Creek during the time of visit. This wetland was larger than the
upper marsh and the upper part was dominated by small-flowered bulrush and Sitka sedge. The
lower part of the wetland had Equisetum-dominated open water, rimmed with Sitka willow. The
water table was 10-15 inches above the soil surface over most of the wetland and the soil was a
sedge peat of the Kina Series except in the upper part, where the flooding stream was washing
sediment into the wetland.
This wetland is the northern part of the larger wetland complex along Swampy Trib and the East
Trib of Switzer Creek in 2011. This area was also included in the wetland assessment done in
Sept. of 2011 using the new wetland assessment methodology developed by Paul Adamus. See
Appendix II.
Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
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Wetland #28 - Portions of this large wetland are intercepted by upper Switzer Creek. It was
assigned to category B based partly on relatively high ratings for Groundwater Discharge,
Sediment/Toxicant Retention, Nutrient Export, Salmonid Habitat, Wildlife Habitat, and
Recreational Use Potential (Table 2). Ratings were relatively low for Groundwater Recharge
and Erosion Sensitivity. This wetland was not assigned to category A partly because of its
relatively high PP (lower public preference) and PA (more numerous practicable alternatives)
scores based on 1987 information for the closest wetland (L15) assessed at that time. This
wetland is a complex of marshy uplifted beach meadow and bog in the southern part (mostly
outside the study unit) and scrub-shrub and forested wetland in the northern part. The forested
wetland overstory is dominated by large spruce with an understory of young hemlock. The
wetter swales were dominated by skunk cabbage, devils club and liverworts and the drier
hummocks by spiny wood fern. The scrub-shrub community is dominated by Sitka alder, Sitka
willow and high bush cranberry with an understory of skunk cabbage and Sitka sedge. Soils in
both communities have been mapped as hydric soils – mostly mucky peats of the Kena and
Maybeso Series, and during the time of visit were saturated throughout all of the wetland (except
on scattered hummocks).
This wetland is the southeastern part of the larger wetland complex delineated along the West
Trib of Switzer Creek in 2011. This area was also included in the wetland assessment done in
Sept. of 2011 using the new wetland assessment methodology developed by Paul Adamus. See
Appendix II.
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Wetland Delineation Report for CBJ Switzer Creek Area Inventory and Analysis - 2012
55
" 1987 Adamus Methodology" criteria used for assessing relative level of each function
Ratings in column 2 are VH (very high, 7), H (high, 6), MH (moderately high, 5), M (moderate, 4), ML (moderately low, 3), L (low, 2), or VL (very
low). C1, C5, etc. refer to cell addresses in the accompanying spreadsheet where the data can be found (see Appendix A for data categories). The
weight shown for each function is the one recommended by the CDD (1997) report.
Important Note: When scoring each function, begin with its top row and then proceed downward row by row only if the criteria in the row being
examined are not met. Only one rating (the highest applicable one) should be assigned per function per wetland.
Function Rating Criteria
Groundwater
Discharge
H (6) if 1) Wetland is non-tidal (C9=0) AND
2) either is at the toe of a steep slope (C5= TS) or is on a slope of greater than 15% (C6= H) or in an alluvial fan or avalanche chute
(C4= AC) or is intersected by a perennial stream or is within 50 ft of one (C11= PI).
L if Wetland is tidal (C9= Y) and is not intersected by a perennial stream or within 50 ft of one (C11= not PI & not P50)
and is not at toe of a steep slope (C5= not TS) and not in alluvial fan (C4= not AF) and is on a slope of less than 7% (C6= L)
M if not H and not L
Sediment/
Toxicant
Retention
(weight= 6)
H (6) if 1) Wetland is at toe of a steep slope or on a flat (C5= TS or F) and has a slope of less than 15% (C6= M or L) and its soil is
predominantly peat (C7= Y), OR
2) Wetland is not intersected by a perennial or ephemeral stream (C11= not PI & not Ei) and is on a slope of less than 7% (C6= L)
MH (5) if Wetland is not intersected by a perennial or ephemeral stream (C11= not PI & not Ei ) and its gradient is less than 15% (C6= not H)
and its soil is predominantly peat (C7=Y)
L (2) if Wetland gradient is greater than 15% (C6= H) and pit-mound topographic variation is not extensive or great (C17= 0 or T1L)
ML (3) if not H and not MH and not L
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Function Rating Criteria
Nutrient
Export
(weight= 7)
H (6) if 1) Wetland is tidal (C9= Y) OR
2) Wetland is intersected by a perennial stream (C11= PI) AND ANY of 2a, 2b, or 2c
2a) its surface water levels experience large fluctuation (C13= H) or
2b) its area covered only seasonally by surface water is extensive (C15= H)
2c) it is dominated by trees (C18= T50) or deciduous shrubs (C19= D50)
L (2) if 1) There is no perennial stream within 200 ft of the wetland and not intersected by ephemeral stream (C11= not PI & not P50 & not
P200 & not Ei), and any of the following:
2a) is mostly covered by wetland moss (C21= M50) or
2b) the wetland’s surface water levels experience little or no fluctuation (C13= L) or
2c) the area covered only seasonally by surface water is very limited (C15= S)
M (4) if not H and not L
Riparian
Support
(weight= 10)
H (6) if 1) Wetland is intersected by a perennial stream (C11= PI) or is within an annual floodplain (C12= FP) AND EITHER
1a) alder shrub covers at least half of the wetland’s vegetated area or stream bank (C19= A50 or A90), or
1b) deciduous shrubs/trees cover more than 90% of the wetland’s vegetated area or stream bank (C20= D90).
OR
2) Wetland is intersected by an ephemeral stream (C11= Ei) and
2a) alder shrub covers more than 90% of the wetland’s vegetated area or stream bank (C19= A90) or
2b) deciduous shrubs/trees cover more than 50% of the wetland’s vegetated area or stream bank (C20= D50).
MH (5) if 1) Wetland is intersected by a perennial stream (C11= PI) or is within its annual floodplain (C12= FP) AND EITHER
1a) alder shrub covers at least 1% of the wetland’s vegetated area or stream bank (C19= A1), or
1b) deciduous shrubs/trees cover more than 50% of the wetland’s vegetated area or stream bank (C20= D50).
OR
2) Wetland is intersected by an ephemeral stream (C11= Ei) or is within 50 ft of a perennial stream (C11= PI) AND
2a) alder shrub covers more than 50% of the wetland’s vegetated area or stream bank (C19= A50) or
2b) deciduous shrubs/trees cover more than 1% of the wetland’s vegetated area or stream bank (C20= D1).
L (2) if There is no perennial or ephemeral stream within 50 ft of the wetland (C11= not PI & not Ei & not P50 & not Ei), and the wetland
contains less than 1% deciduous shrubs/trees (C20= 0)
ML (3) if not H and not L and not MH
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Function Rating Criteria
Salmonid
Habitat
(weight= 11)
VH (7) if 1) Wetland is tidal (C9= Y), OR
2) salmonid fish can access part of the wetland year-round (C10=P) and habitat quality (pools, undercut banks, wood, etc.) is good
(C14= H)
H (6) if Salmonid fish can access part of the wetland year-round (C10= P) and habitat quality is moderate (C14=H)
MH(5) if Salmonid fish can access part of the wetland year-round (C10= P) and habitat quality is low (C14= M or L).
ML (3) if Salmonid fish can access part of the wetland seasonally (C10= S) and habitat quality is moderate or high (C14= M or H).
L (2) if Salmonid fish can access part of the wetland seasonally (C10= S) and habitat quality is low (C14=L).
VL (1) if Salmonid fish cannot access the wetland at any time (C10= 0)
Erosion
Sensitivity
(weight= 7)
H (6) if Wetland is on a slope of greater than 15% (C6= H) and its predominant soil is peat (C7= Y)
MH(5) if Wetland is on a slope of greater than 15% (C6= H) and its predominant soil is not peat (C7= 0)
ML (3) if Wetland is on a slope of greater than 7% (C6= M or H) and its predominant soil is peat (C7= Y)
L (2) if Not H and not ML and not MH
Groundwater
Recharge
(weight= 7)
H (6) if Wetland is not in an alluvial fan or avalanche chute (C4= not AF & not AC) or tidal area (C9= 0) AND
Wetland is not intersected by a perennial stream or within 50 ft of one (C11= not PI & not P50) and is either on a plateau (C5= P)
or has a slope of mostly less than 7% (C6= L)
L (2) if Wetland is tidal (C9= Y) or is intersected by a perennial stream (C11= PI)
M (4) if Not H and not L
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Function Rating Criteria
Hydrologic
Control
(weight= 9)
H (6) if 1) Wetland non-tidal (C9= 0) and is on a slope of less than 7% (C6= L) and is not intersected by a stream (either perennial or
ephemeral) (C11= not PI & not Ei) OR
2) Wetland is not in a mid-slope or toe-slope position (C5= not TS & not MS) and is in a floodplain (C12= FP) or has extensive
seasonal ponding of surface water (C15= H) or has extensive and large pit-mound topography (C17= T25H)
MH(5) if Wetland is non-tidal (C9= 0) and
has moderate-extensive seasonal ponding of surface water (C15= M) or moderate water level fluctuations (C13= M) or extensive
but mild pit-mound topography (C17= T25L)
L (2) if Wetland is tidal (C9= Y)
ML (3) if Not H and not MH and not L
Detention
Value*
(weight= 9)
H (6) if
L(2) if
Wetland is non-tidal (C9= 0) and uphill areas have peat soils (C8= Y) and relatively extensive development (C26= H)
Wetland is tidal (C9= Y) and uphill areas have little or no development (C26= L)
M (4) if Not H and not L
Recreational
Use Potential
(weight= 5)
H (6) if Developed hiking trails go to or near (within 100 ft of) wetland and wetland is within 0.5 mile of trailhead (C30= H) and wetland is
on public land (C31= C)
MH (5) if Developed hiking trails go to or near the wetland but wetland is farther than 0.5 mile from trailhead (C30= M) and wetland is on
public land (C31= C)
L (2) if No hiking trails go to or near the wetland and wetland is more than 0.5 mile from road (C30= 0) and wetland is on private land
(C31= P)
ML (3) if No trails are within 100 ft of wetland but the wetland is within 0.5 mile of a road (C30= L) and wetland is on public land (C31= C)
Recreational
Use Actual
(weight= 6)
H (6) if Results of a 1987 recreational survey indicated relatively high use of this wetland or the closest one (C32= H)
MH (5) if Results of a 1987 recreational survey indicated moderately high use of this wetland or the closest one (C32= MH)
L (2) if Results of a 1987 recreational survey indicated relatively low use of this wetland or the closest one (C32= L)
ML (3) if Results of a 1987 recreational survey indicated relatively moderately low use of this wetland or the closest one (C32= ML)
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Function Rating Criteria
Wildlife
Support*
(weight=
11.5)
H (6) if 1) Wetland is tidal (C9= Y) or contains or adjoins at least 1 acre of perennially ponded non-tidal water (C16= PW) OR
2) Wetland is contiguous to a large forested tract and not separated from it by roads (C25= C) and has little or no uphill development
(C26= L), and has not been altered by nearby ditches or roads (C28= 0), and has less than 10% cover of non-native plants (C29= 0),
and 2a or 2b:
2a) creates a gap in the canopy of an extensive surrounding forest (C23= CC) and is not primarily wetland moss (C21= 0 or M1) and is
(2a1) distant from the nearest residence (C27= F) or (2a2) has many vegetation structural forms (C22= H), OR
2b) does not create such a gap (C25= 0) and is not within 100 ft of a residence (C27= M or F), and has more than 90% total tree cover
(C18=T90) or more than 50% deciduous tree/shrub cover (C20= D50), or has salmonid access (C10= S or P), or at least one large-
diameter tree (C24= BT), or extensive pit-mound topography (C17= T25L or T25H), or many vegetation forms (C22= H)
MH (5) if Wetland is contiguous to a large forested tract and not separated from it by roads (C25= C) and has less than 10% cover of non-native
plants (C29= 0), and EITHER
a) creates a gap in the canopy of an extensive surrounding forest (C23= CC) and is not within 100 ft of a residence (C27= M or F) and
has some diversity of vegetation structural forms (C22= not L) OR
b) has more than 50% deciduous tree/shrub cover (C18= T50 or C20= D50) or is intersected by or within 50 ft of a perennial stream
(C11= PI or P50) or is more than 0.5 mile from a road and lacks developed trails (C30= 0)
L (2) if 1) Wetland does not create a gap in the canopy of an extensive surrounding forest (C23= 0), and is not tidal (C9= 0), and is not within
500 ft of perennially ponded non-tidal water (C16= 0), and does not have salmonid access (C10= 0), and has no large-diameter trees
(C24= not BT & not MT), and has little or no pit-mound topography (C17= 0 or T1L), and has 1a or 1b:
1a) >90% moss cover (C21= M90) or more than 10% cover of non-native plants (C29= Y) or only a few vegetation structural forms
(C22= L), OR
1b) is not contiguous to a large forested tract (C25= 0) and has any of the following: extensive development in uphill areas (C26= H)
or is close to a residence (C27= N) or has been altered by nearby ditches or roads (C28= Y) or has developed trails and a trailhead
nearby (C30= H).
ML (3) if Not H and not ML and not L
* Detention Value was termed “Downslope Beneficiary Sites” in the ARA (1987) and CDD (1997) reports. Wildlife Support is the merger of “Disturbance-sensitive Wildlife” and
“Regional Ecological Diversity” in those reports; their respective weights were averaged.
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Appendix II - WESPAK-SE for Switzer Creek - 2011
Application of Draft WESPAK-SE
for Rapid Assessment of Functions and Values of Wetlands
Associated With CBJ – Switzer Creek (Eastern) Area Land Inventory
and Development Analysis
Draft Report for City and Borough of Juneau
by:
Paul R. Adamus, Ph.D.
Adamus Resource Assessment, Inc.
Corvallis, OR
and
Koren Bosworth
Bosworth Botanical Consulting
Juneau, AK
December 6, 2011
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61
Background
Assessments of the impacts of development on wetlands, and the mitigation of those impacts, commonly focus
on the “functions and values” of the wetlands as is required by the federal Clean Water Act. “Functions” are
what a wetland can do naturally (such as store water). “Values” reflect the importance society usually places on
a particular wetland as reflected partly by the functions that wetland provides relative to the locations of users of
those functions.
A method for rapidly assessing particular functions and values of wetlands in Southeast Alaska was first
published in 1987 (Adamus 1987) and used as a basis for the Juneau Wetlands Management Plan (CDD 1997).
Recently, the criteria used to define relative levels of each function or value were modified slightly from the
1987 method to reflect new scientific information (Adamus & Bosworth 2007, 2010), but the update was not
intended to be comprehensive nor make the method applicable to wetlands outside the City-Borough of Juneau.
For use throughout all of Southeast Alaska, a more scientifically-thorough update termed WESPAK-SE
(Wetland Ecosystem Services Protocol for Alaska – Southeast) was funded in early 2011 by the US Fish and
Wildlife Service through a grant to the Southeast Alaska Land Trust (SEAL Trust). That has now been
completed in draft, staffs from some agencies have been trained in its use, and a final version is currently
undergoing peer review. It differs substantially from the 1987 and 2007 Juneau methods. Further description is
provided in Appendix A.
In September 2011, data forms had been completed for WESPAK-SE. The eastern part of the Switzer Creek
project area wetlands were then assessed in September, 2011. Once the draft versions of the WESPAK-SE
models for estimating functions and values were completed, the collected field data were run through the
models and results are described in this report.
Methods
On September 13, 2011, Adamus and Bosworth visited the eastern project area and assessed it using WESPAK-
SE. This report includes the contiguous wetlands along the East and West Tribs of Switzer Creek and the
isolated wetland along the north edge of the West Trib. This wetland, though isolated, was visited and assessed
and is part of the same watershed and has wetland characteristics almost identical to those of the marsh in the
northern part of the East Trib of Switzer Creek.
Results
The numbers shown in the tables below are extracted from a table that includes the results from 26 other non-
tidal sites around communities in SE Alaska. The first shows the function and value scores paired by site, and
on the far right I've included some summary statistics calculated for all 26 sites. You can see that for some
functions (and values), there's a wider numeric range among the scores of the test sites than for others. Also,
the scores for some functions average higher than for others. This is to be expected, because (for instance) not
every wetland is accessible to fish, but nearly every wetland has the potential to remove nitrate to some degree,
resulting in a higher regional median score. In the second table down, on each row I've highlighted sites that
were in the top 10% for each function (green) and bottom 10% for each function (orange). In the last table, I've
done the same for the values of the sites. In the future, the scores could also be mathematically re-scaled so
they fill each function's entire potential range of 0 to 10 if that is desired, though I hesitate to do that with a
sample size of only ~30 sites.
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Summary Statistics for all 26 non-tidal sites
FUNCTIONS & VALUES PAIRED BY SITE
Switzer Min Min Max Max Median Median
Specific Functions or Values: F V F V F V F V
Water Storage (WS) 3.45 2.22 2.33 1.11 5.65 10.00 3.45 2.50
Stream Flow Support (SFS) 6.22 2.39 0.00 0.90 6.46 4.34 4.24 1.27
Streamwater Cooling (WC) 9.26 5.83 0.00 0.00 9.26 6.75 1.90 2.50
Streamwater Warming (WW) 3.50 6.41 1.33 4.93 8.00 7.12 4.25 5.79
Sediment & Toxicant Retention &
Stabilization (SR) 5.07 5.30 1.64 2.67 5.59 5.83 3.20 3.71
Phosphorus Retention (PR) 5.59 6.33 4.20 1.67 6.87 6.67 4.88 3.33
Nitrate Removal & Retention (NR) 5.99 6.30 2.71 2.50 6.88 6.48 4.78 5.28
Carbon Sequestration (CS) 4.23 4.03 7.82 4.72
Organic Nutrient Export (OE) 4.72 2.71 5.82 4.01
Aquatic Invertebrate Habitat (INV) 5.17 6.22 3.61 1.76 6.30 6.67 4.95 2.62
Anadromous Fish Habitat (FA) 7.66 3.30 0.00 1.32 8.50 6.80 0.00 3.04
Resident & Other Fish Habitat (FR) 6.76 1.57 0.00 0.00 8.09 8.74 0.00 3.33
Amphibian Habitat (AM) 6.41 5.00 4.93 5.00 7.12 5.46 5.79 5.00
Waterbird Feeding Habitat (WBF) 4.72 5.00 0.00 0.00 6.22 10.00 3.88 0.00
Waterbird Nesting Habitat (WBN) 6.57 10.00 0.00 0.00 7.37 10.00 2.52 0.00
Songbird, Raptor, & Mammal Habitat
(SBM) 5.20 7.50 3.97 5.00 7.15 7.50 4.76 7.50
Pollinator Habitat (POL) 5.07 5.00 1.33 0.00 5.54 5.00 3.68 5.00
Native Plant Habitat (PH) 6.11 5.07 3.02 4.16 7.46 7.45 5.43 5.54
Public Use & Recognition (PU) 3.56 1.67 7.40 3.34
Subsistence & Provisioning Services
(Subsis) 0.00 0.00 10.00 3.33
Wetland Sensitivity 3.22 1.09 3.56 2.33
Wetland Ecological Condition 6.67 1.67 7.78 5.10
Wetland Stressors 1.11 0.56 5.37 1.26
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FUNCTION SCORES ONLY (for each function:
top 10% highlighted in green, bottom 10% in
orange)
Switzer
Water Storage (WS) 3.45
Stream Flow Support (SFS) 6.22
Streamwater Cooling (WC) 9.26
Streamwater Warming (WW) 3.50
Sediment & Toxicant Retention &
Stabilization (SR) 5.07
Phosphorus Retention (PR) 5.59
Nitrate Removal & Retention (NR) 5.99
Carbon Sequestration (CS) 4.23
Organic Nutrient Export (OE) 4.72
Aquatic Invertebrate Habitat (INV) 5.17
Anadromous Fish Habitat (FA) 7.66
Resident & Other Fish Habitat (FR) 6.76
Amphibian Habitat (AM) 6.41
Waterbird Feeding Habitat (WBF) 4.72
Waterbird Nesting Habitat (WBN) 6.57
Songbird, Raptor, & Mammal Habitat
(SBM) 5.20
Pollinator Habitat (POL) 5.07
Native Plant Habitat (PH) 6.11
VALUE SCORES ONLY (for each value: top
10% highlighted in green, bottom 10% in orange)
Switzer
Water Storage (WS) 2.22
Stream Flow Support (SFS) 2.39
Streamwater Cooling (WC) 5.83
Streamwater Warming (WW) 6.41
Sediment & Toxicant Retention & Stabilization
(SR) 5.30
Phosphorus Retention (PR) 6.33
Nitrate Removal & Retention (NR) 6.30
Aquatic Invertebrate Habitat (INV) 6.22
Anadromous Fish Habitat (FA) 3.30
Resident & Other Fish Habitat (FR) 1.57
Amphibian Habitat (AM) 5.00
Waterbird Feeding Habitat (WBF) 5.00
Waterbird Nesting Habitat (WBN) 10.00
Songbird, Raptor, & Mammal Habitat (SBM) 7.50
Pollinator Habitat (POL) 5.00
Native Plant Habitat (PH) 5.07
Public Use & Recognition (PU) 3.56
Subsistence & Provisioning Services (Subsis) 0.00
Wetland Sensitivity 3.22
Wetland Ecological Condition 6.67
Wetland Stressors 1.11
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Even when a wetland provides a high level of function, that functioning at a particular location is not
necessarily recognized as valuable by society, using common indicators of social importance such as species
rarity and position relative to important human uses and infrastructure.
Based on the assessment findings above, the project area wetlands scored at or above the regional median score
for 16 out of 18 functions and at or above the regional median score for 16 out of 20 values. The wetlands
scored in the top 10% for 3 out of 18 functions and 6 out of 20 values. They scored in the lowest 10% for 0
functions and 3 out of 20 of the values.
Literature Cited
Adamus, P.R. 1987. Juneau Wetlands: An Analysis of Functions and Values. USEPA and Dept. of Community
Development, Juneau, Alaska.
Adamus, P.R. and K. Bosworth. 2007. Delineation and Functional Rating of Jurisdictional Wetlands on
Potentially Developable City-owned Parcels in Juneau, Alaska. Community Development Department, Juneau,
AK.
Adamus, P.R. and K. Bosworth. 2010. Delineation and Functional Rating of Jurisdictional Wetlands on Two City-
owned Parcels in Juneau, Alaska. Community Development Department, Juneau, AK.
Adamus, P.R. and K. Bosworth. 2011. Rapid Assessment of Functions and Values of Wetlands
Associated With Stage 3 Tailings Expansion for Hecla Greens Creek Mining Company. Report to Hecla Greens
Creek Mining Company, Juneau, AK.
Adamus, P.R. 2011 (draft). WESPAK-SE: Logic Models for Rapidly Assessing the Ecosystem Services of
Wetlands of Southeast Alaska. Draft report to Southeast Alaska Land Trust and US Fish & Wildlife Service,
Juneau, AK.
Bosworth Botanical Consulting. 2011. Jurisdictional Wetland Delineation Report, Stage 3 Tailings Expansion.
Report to Hecla Greens Creek Mining Company.
Community Development Department (CDD), City and Borough of Juneau. 1997. Revised City and Borough
of Juneau Wetlands Management Plan. CDD, Juneau, AK.
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Background on WESPAK-SE
The Wetland Ecological Services Protocol for Alaska: Southeast (WESPAK-SE) is a science-based field
method for rapidly assessing tidal and non-tidal wetlands of Southeast Alaska. Input data are categorical
choices based on observations (not measurements) made during a single half-day visit to a wetland, as well as
from interpretation of generally available maps and resource information. The data are entered into an Excel
spreadsheet that instantly generates scores for 23 functions and values of a non-tidal wetlands, or 11 functions
and values of a tidal wetland. For tidal wetlands, WESPAK-SE is applicable only to salt marshes and wooded
tidal habitats, not to eelgrass, kelp, or other vegetated tidal habitats. WESPAK-SE is applicable to wetlands at
all elevations of Southeast Alaska, from Yakutat south to the Canadian border.
WESPAK-SE results may not always be more accurate than ratings of wetland sites made by someone who is a
specialist on a particular function, particularly if they are experienced locally. However, such expertise is
seldom routinely available to wetland regulators for every function of concern. Moreover, as a standardized
approach, WESPAK-SE provides consistency and comparability when prioritizing wetlands or assessing the
consequences of alterations on wetland ecosystem services.
The model formula WESPAK-SE uses to generate the score for each wetland function or value is logic-based
rather than mechanistic. Each model is described in a document currently being peer-reviewed, and consists of
indicator variables (indicators) and assumed ranks for the conditions potentially associated with each indicator
as it pertains to each wetland function. From a pool of 125 rapidly observable indicators, WESPAK-SE uses up
to 50 indicators (depending on function or value) drawn from a pool of 125 to score non-tidal wetlands, and up
to 27 indicators from a pool of 85 to score tidal wetlands.
For most functions, WESPAK-SE groups the indicators by the underlying processes they inform. Weights were
assigned both to individual indicators within a process, and the processes that comprise a function. Indicator
and process selection was based on the author’s experience and review of much of the literature compiled
initially in an indexed bibliography of science relevant to Southeast Alaskan ecosystem services (available
electronically from SEAL Trust or the author). Field data forms that are used to assess each indicator were
field-tested by the author in wetlands throughout Southeast Alaska during 2011.
WESPAK-SE provides models for both functions and values. It is very important to understand the conceptual
difference. Functions are what a wetland potentially does, such as store water. Values attempt to answer the
“So What?” question, partly by considering where a wetland is positioned relative to people or features that
might benefit from its services, and whether its species or habitats have special designations.
WESPAK-SE is a regionalized modification of ORWAP2, the Oregon Rapid Wetland Assessment Protocol,
developed by the same author from 2006 to 2009, which built on indicator-function relationships first described
by the author in the early 1980s and in numerous agency publications and methods since then, including the
2 http://oregonstatelands.us/DSL/WETLAND/or_wet_prot.shtml
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66
1993 Juneau Wetlands Management Plan. The State of Oregon, in collaboration with the US Army Corps of
Engineers Portland District, has required ORWAP assessments since 2009 for all major wetlands permitting and
mitigation. The provinces of Alberta and Nova Scotia and an international private non-profit group have also
expressed a desire to regionalize a generic version of the Oregon method (named WESPUS)3 for their needs. If
interest is sufficient, WESPUS or WESPAK-SE could be modified for use elsewhere in Alaska. At the behest
of an Interagency Review Team (IRT) and Southeast Alaska Land Trust (SEAL Trust), an independent
consulting firm was contracted in 2009 to review and critique 16 wetland rapid assessment methods potentially
applicable to Southeast Alaska. They selected ORWAP/WESPUS and recommended its adaptation and
calibration in the region (CH2M Hill, 2010). The City and Borough of Juneau is considering using this
WESPAK-SE method to re-prioritize its wetlands in 2012-2013, and SEAL Trust intends to use it in
collaboration with the US Army Corps of Engineers for their In-Lieu Fee Mitigation program.
An operable version of the WESPAK-SE spreadsheet and data forms, along with a manual, will be released
publicly in February 2012, and will reflect revisions based on the peer review. It is anticipated that training will
also be available during 2012.
3 http://people.oregonstate.edu/~adamusp/WESPUS/