Reed College Canyon

Canyon Resources

"Reed Canyon Reach"

from Crystal Springs Creek Fish and Wildlife Habitat Assessment

The following is an excerpt from a fish and wildlife habitat assessment of Crystal Springs Creek, which extends from its headwaters on the Reed campus to its confluence with Johnson Creek in Sellwood. The assessment was prepared for Portland Parks and Recreation by Adolfson Associates, Inc.

Crystal Springs Creek Fish and Wildlife Habitat Assessment

Final Draft, June 2001

III.2 Habitat Assessment
III.2.7 Reach 7. Reed Canyon
III.2.7.1 Reach Description
Habitats
Fish and Wildlife Use
Special Features
Hydrology and Water Quality
Current Land Use
III.2.7.2 Wildlife Habitat Assessment
III.2.7.3 Summary of ODFW Data
III.2.7.4 Stream and Riparian Functional Assessment (SRFA)
III.2.7.5 System Stresses and Sources
III.2.7.6 Reach 7 Habitat Condition Summary
V. Restoration Assessment
V.1.7 Reach 7 ? Reed Canyon

 

III.2.7 Reach 7. Reed Canyon

III.2.7.1 Reach Description

The final reach in the CSC study area includes the entire Reed Creek channel located on the Reed College campus, as well as Reed Lake. The reach begins adjacent to the east lot of the Rivelli farm, and continues east through the west part of campus and up to the lake. Reed Lake is a 4-acre spring-fed shallow water body that is contained within the upper part of reed canyon. The college swimming pool used to be adjacent to the west side of the lake, near the outlet into the channel. However, in fall of 2000 the swimming pool was removed and the area back filled. Flows from the lake are diverted through an out-flow grate into a channel that passes along the north margin of campus, under the reed theater, and towards the Rivelli farm. The reach contains approximately 2,200 feet of open water and stream habitat.

Habitats within this reach include Reed Lake, the emergent wetland and marsh surrounding the lake, forested riparian and upland habitats, and the Reed Creek channel. This reach is one headwater area for CSC and includes several springs located at the base of the hill slope at the eastern boundary of the canyon. The springs feed a large marsh habitat dominated by open water and emergent communities east of the lake. The marsh transitions into the lake at the location of a former beaver dam that has accelerated the area?s succession from open water to emergent and scrub-shrub wetlands. The lake, bordered by forested canyon walls, drains to an outlet on a man-made embankment and discharges into a natural stream channel that occupies the lower portion of the reach.

Habitats

Instream Habitat - The stream channel within this reach contains a higher gradient than the other reaches. Instream habitat throughout this reach is the most diverse within the study area, with a sand dominated stream bottom including a full range of sizes of gravels and cobbles. The average stream channel width is approximately 10 feet, and the average depth is approximately 4 inches. Riparian vegetation along the majority of the stream channel is dense mixed deciduous/coniferous forest providing shade over approximately 50 percent of the stream. Instream structure is augmented by many large boulders, large downed logs that both bridge and are anchored in the stream channel, and large amounts of leaf litter and vegetative debris along the channel margins. The stream contains several small runs, riffles, braided sections, and pools of variable depth, although no pools were over one-foot deep. The channel starts near the area of the former swimming pool on campus, just below Reed Lake. The lake is connected to the stream channel by an underground pipe approximately 200 feet in length. This area presents a potential opportunity for riparian habitat restoration and a possible surface connection between the stream channel and the lake.

Riparian Habitat ? The majority of the channel length contains a dense canopy dominated by red alder (Alnus rubra), big-leaf maple (Acer macrophyllum), and western red cedar (Thuja plicata). Canopy cover varies from 25 to 70 percent, with large amounts of downed wood and standing snags throughout the lower half of this reach. The understory contains several areas of isolated emergent wetland adjacent to or near the channel, dominated by stands of spreading bentgrass (Agrostis stolonifera), skunk cabbage (Lysichitum americanum), spotted touch-me-not (Impatiens capensis), creeping spikerush (Eleocharis palustris), and field horsetail (Equisetum arvense). However, the riparian corridor is generally less than 100 feet wide, and quickly transitions into upland. Much of Reed Lake also contains a mixed canopy of red alder, big-leaf maple, and western red cedar, as well as Douglas-fir (Pseudotsuga menziesii) and grand fir (Abies grandis). A dense emergent understory is dominated in areas adjacent to the water by pacific willow (Salix lucida var. lasiandra), Douglas? spiraea (Spiraea douglasii), and red elderberry (Sambucus racemosa). The remainder of the understory is composed of large amounts of non-native and small numbers of native grasses, sedges, and forbs. The majority of the emergent habitat associated with Reed Lake is dominated by dense growths of reed canarygrass (Phalaris arundinaceae) surrounded by shallow open water areas. This species is actively suppressing the growth of a more diverse emergent understory in the upper canyon.

Upland Habitat ? Upland vegetation is found throughout the canyon and along the stream channel, and is dominated by a canopy of Douglas-fir, western red cedar, and big-leaf maple. A dense shrub understory surrounds Reed Lake in areas without a prominent canopy, and includes native shrubs in the upland areas such as serviceberry (Amelanchier alnifolia), vine maple (Acer circinatum), Douglas?s hawthorn (Crataegus douglasii), bitter cherry (Prunus emarginata), wild rose (Rosa sp.), and snowberry (Symphoricarpos albus). However, a large proportion of this vegetation is heavily invaded or suppressed by dense growths of non-native or invasive species, including English holly (Ilex aquifolium), Himalayan blackberry (Rubus discolor), English hawthorn (Crataegus laevigata), and English Ivy (Hedera helix). English ivy has blanketed much of the herbaceous understory of the upland forest, so that only a few native herbs such as sword fern (Polystichum munitum) remain. Uplands associated with the stream channel include a canopy of Douglas fir and planted trees of various species, including some pines (Pinus sp.). The understory in these areas is dominated either by weedy shrubs including Scotch broom (Cytisus scoparius), English hawthorn, and wild rose, or upland grasses including bluegrass (Poa sp.) and tall fescue (Festuca arundinaceae). English ivy is a prominent invasive species in these areas as well, and limits the herbaceous understory as well as posing a threat to many of the upland trees by climbing their canopies.

Fish and Wildlife Use

Good quality instream, riparian, and upland habitats occur within this reach, usually with only minimal interruptions of good habitat areas by more disturbed areas. Nearly all habitats located within this reach have an extremely high refuge value for most species of wildlife due to the dense vegetative cover, relatively low disturbance rates, and structural diversity contained throughout the reach. Species that were observed during the field investigations, have been previously documented within the reach area, or are expected to occur due to suitable habitat conditions are discussed below.

Fish ? Adolfson observed riffle sculpin (Cottus gulosus) and redside shiner (Richardsonius balteatus) in the farthest downstream portion of the reach. No fish were observed during the field investigation within Reed Lake, but likely species inhabiting the large, shallow lake include carp (Cyprinus carpio), largemouth bass (Micropterus salmoides), smallmouth bass (Micropterus dolomieu), bluegill (Lepomis macrochirus), as well as potential coho (Oncorhynchus kisutch), chinook (O. tshawytscha), steelhead and rainbow trout (Oncorhynchus mykiss), and cutthroat (Oncorhynchus clarki). In addition, ODFW and Mr. Clyde Brummell have historically operated fish hatch boxes in the lake area and released salmon and trout fingerlings below the dam, with the intention of strengthening the populations (in both the lake and stream) of cutthroats, steelheads, and coho living there.

Aquatic Invertebrates ? Adolfson conducted three invertebrate samplings within CSC in this reach, and observed increased species diversity compared with Reach 6 downstream, and increased populations of all species compared with all other reaches in the study area. Included in the samples were large numbers of amphipods, trichoptera (several species), and mollusks. Also included in the samples were lower numbers of plenaria, nematodes, and coleoptera (riffle beetles). The increase in species diversity and relative numbers of aquatic invertebrates illustrates improved instream conditions throughout this reach compared with all downstream reaches.

Amphibians ? Adolfson did not observe any amphibians during the field investigations, but good breeding and foraging habitat is located throughout Reed Lake due to the shallow water, high vegetative cover values, and logs and other structures present in the lake. Expected species include the Pacific chorus frog (Pseudacris regilla), northwestern salamander (Ambystoma gracile) long-toed salamander (Ambystoma macrodactylum), and roughskin newt (Taricha granulosa). In addition, portions of the riparian and upland forests in this reach contain dense woody debris on the forest floor and rotted tree stumps, which provide good habitat for terrestrial salamanders including ensatina (Ensatina eschscholtzii).

Reptiles ? Adolfson observed both aquatic and terrestrial garter snakes (Thamnophis sp.) during the field investigations of this reach. Reed Lake also may provide suitable habitat for western pond turtle (Clemmys marmorata), although none were observed during the field investigations.

Birds ? Adolfson identified ten birds within the reach during the field surveys: ruby-crowned kinglet (Regulus calendula), white-crowned sparrow (Zonotrichia leucophrys), fox sparrow (Passerella iliaca), bank swallow (Riparia riparia), belted kingfisher (Ceryle alcyon), downy woodpecker (Picoides pubescens), brown-headed cowbird (Molothrus ater), marsh wren (Cistothorus palustris), red-tailed hawk (Buteo jamaicensis), and mallard (Anas platyrhynchos). Expected species for this reach are numerous, and include a large population of common ducks and resident passerines, wading birds including great blue herons, raptors including hawks and owls, as well as several neotropical migrants such as warblers. Due to the proximity of this reach to large areas of open space including the Reed College campus and the Eastmoreland Golf Course, a large and diverse bird population can be expected. Screech owls have been documented in nest boxes surrounding Reed Lake.

Mammals ? Adolfson identified raccoon (Procyon lotor), mule deer (Odocoileus hemionus ssp. columbianus), woodrat (Neotoma sp.), western gray squirrel (Sciurus griseus), and coyote (Canis latrans) presence within this reach, primarily by scat and track identification. No other mammals were observed during the field investigations, but habitat within the reach is likely productive for small mammals including mice (Peromyscus sp.), voles (Microtus sp.), bats (Myotis sp. and Eptesicus sp.), pocket gophers (Thomomys sp.), nutria (Myocastor coypus), Virginia opossum (Didelphis virginiana), and muskrat (Ondatra zibethicus). Beaver may also be active within the reach, and the species has had a strong historical presence in and near the lake due to an abundance of quality habitat.

Special Features

As noted above, the Reed Canyon reach contains the some of the highest quality terrestrial habitat within the Crystal Springs watershed, as well as within the 11,500 acres of the Johnson Creek basin located in Portland. The lower section of this reach, downstream of Reed Lake, contains good quality in-stream habitat with exposed gravels and cobbles, natural bank conditions, good streamside cover, and a wide vegetated riparian buffer. Sedimentation and embeddedness are limited in this reach, unlike the disturbed, lower gradient channel conditions found in downstream reaches.

This is the headwater reach fed by multiple springs emerging from the base of Portland Terrace deposits at the east end of the canyon. Water quality and temperature conditions are equaled only by the springs located within Reach 5. The cool, clean water with near constant year-round flows, and the gravel substrate provide potential spawning habitat for coho salmon, steelhead, and cutthroat trout (if downstream fish passage barriers can be addressed).

Hydrology and Water Quality

Reach 7 is the headwater reach of the Reed Creek branch of CSC and includes lake, steep gradient/high velocity stream, and spring source wetland hydrologic regimes. The sources of Reed Creek are three or four major and several lesser springs in the upper canyon; Reed Lake, constructed around the turn of the 20th century, provides a nearly constant level water body. The upper canyon has several impoundments (at least one on private property) which trap spring water prior to discharge to the stream. The discharge from the lake is currently a high velocity culvert section, which is scheduled for replacement by a designed pool/riffle stream segment in 2001/2002. The stream below Reed Lake has a consistently moderate to steep gradient with a fairly uniform, moderate velocity riffle hydrology over cobbles and gravels. Water quality at the headwater sources is high except for elevated nutrients and bacteria. Reed Lake provides a significant source of thermal loading, although it is well shaded. Some waterfowl reside on the lake, but their numbers are small compared to CSL and the Westmoreland Park duck pond.

Current Land Use

This reach is set in the heart of Reed College?s 100-acre campus (institutional use with on-site residential dormitories). Most college buildings and facilities are set back from the rim of the forested canyon. However, the Reed Theater extends into the lower canyon and is constructed over a section of the stream. The Physical Plant and a bermed road crossing are located at the west end of the lake; a swimming pool at this location was removed during the summer of 2000. A single footbridge spans the lake near its midpoint, and a loop trail follows the lake?s perimeter at the base of the canyon. Bordering the canyon to the east and northeast are single family residential homes. Some dumping of yard debris and excavation at the springs is evident in this area. The source of escaped English ivy, a major stress in the understory (discussed below), is both residential and college landscaping.

III.2.7.2 Wildlife Habitat Assessment

This reach contains the highest quality habitat within the CSC watershed. The diversity of habitat types, plant diversity and quantity, and the mosaic of wetland communities make the Reed Canyon the highest quality habitat area within the City of Portland?s portion of the Johnson Creek basin. Some of the vegetative assemblages within this reach can be used for reference sites for other reaches of the Crystal Springs watershed. Table 25 summarizes the habitat assessment for this reach, and the WHA form for this reach can be found in Appendix C.

Table 25. Reach 7 WHA Summary

Wildlife Habitat Score: 81

Range for Crystal Springs Sites: 24-81

Habitat Components

Other Factors

Water: High (28)

Connectivity: Moderate (4)

Food: High (19)

Uniqueness: Low (3)

Cover: High (22)

Disturbance: Moderate (4)

III.2.7.3 Summary of ODFW Data

Adolfson?s Reach 7 is the upstream portion (~ 700 m) of the ODFW Aquatic Inventory Project?s Reach 4. A summary of ODFW Aquatic Inventory Project draft data for Reach 4 is presented in Table 26 below. The stream channel along this reach is in a relatively natural state, without channelization. Refugia and cover for fish within this reach include off channel habitat, woody debris, with some undercut banks and deep pools. In addition, the riparian zone is intact, with both coniferous and deciduous trees providing shade. Shrub cover values are also good for this area. This reach currently includes a fish barrier at the outlet from Reed Lake. ODFW indicate that gradients in this reach are the steepest in the entire basin. ODFW data also show three significant peaks in percent silt and organics occurring within Crystal Springs Creek, with one of these peaks associated with Reed Lake at the upstream end of this reach. In addition, one of the two areas with a significant amount of boulders is located within this reach.

Table 26. ODFW Reach 4 Data Summary

 

ODFW Reach # 4

(Adolfson Reach # 7)

Reach Length

1152 m

Gradient

1.2%

Actively Eroding Banks

10%

Undercut Banks

9%

Average Shade

48%

Dominant Substrates

fine sediment (49%)

gravel (36%)

Dominant Habitat Types

dammed pool (73%)

scour pool (14%)

III.2.7.4 Stream and Riparian Functional Assessment (SRFA)

The Reed Canyon Reach received the highest score in the study area (62 of 81 total possible points, 77%) during the field investigations. For comparison purposes, the range of scores within the CSC study area was 36 to 62. This reach scored high in the natural biological support and specific habitat functions due to the presence of a large area of land containing variable habitat types within the reach. Although significant problems exist with invasive species in this reach, high vegetative cover values, better refuge habitats, and available habitats for most wildlife groups result in the highest score within the CSC study area. Table 27 summarizes the results of this assessment, and scoring decisions for specific functions are presented in Appendix D.

Table 27. Reach 7 SRFA Summary

Function

Group 1

Group 2

Group 3

Total per Function

Maximum Points Possible

Percent of Total Points

Natural Biological Support

1

8

21

30

36

83%

Overall Habitat Functions

0

2

4

6

9

67%

Specific Habitat Functions

0

4

9

13

15

87%

Cultural/ Socio-economic

2

8

3

13

21

62%

TOTALS

3

22

37

62

81

77%

III.2.7.5 System Stresses and Sources

Environmental stresses were identified within this reach, and are listed below in Table 28. The reach contains several stresses to the riparian and instream habitats, including a large and prominent population of non-native and invasive plant species associated with Reed Lake, as well as a fish migration barrier just below the lake. Increased levels of fecal coliform bacteria potentially affect the water quality. A long pattern of heavy sediment deposition at the west end of the lake may produce a sediment flushing problem for downstream portions of CSC if the lake flow is reconnected via a surface connection through the old swimming pool area on reed College campus.

Table 28. Stresses and Sources in Reach 7

Stresses

Sources

  • Sediment accumulation
  • Deep fine sediment deposits at west end of lake
  • Instream habitat fragmentation
  • Poor stream habitat quality immediately downstream of this reach may create a passage barrier for salmonids and other fish species
  • Piped connection between Reed Lake and the stream channel does not allow for salmonid and other fish species to utilize the lake habitat
  • Degraded vegetative community composition
  • Large amounts of exotic and invasive species in and surrounding Reed Lake area
  • Water quality degradation
  • Septic system inputs of nutrients
  • Thermal impacts of Reed Lake

III.2.7.6 Reach 7 Habitat Condition Summary

  • A large population of invasive species now dominates large areas of the riparian and upland habitat areas associated with Reed Lake and the stream channel on campus. The species composition in some areas is so dominated by invasive species that the native flora is completely suppressed.
  • The Portland pipeline is a visual disturbance. This water pipeline enters from the north of the canyon, runs across the marsh, and exits through the south of the canyon.
  • A very thick layer of fine silt is masking the lake's bottom. The water moves very slowly in this part of the canyon, and heavy sediment deposition is creating a gradual but certain transition to a more closed scrub/shrub wetland habitat in place of the lake. The sources of these sediments are unknown but may be related to historical development on the upland slopes above the springs as well as organic material input to the wetland and lake (leaf-fall, decaying vegetation, etc.)
  • The land under the theater is trampled and depleted of nutrients. Little plant life can be expected to survive there, and the riparian community here is entirely absent due to heavy shading.

Reed Lake is a large and shallow water body that may be prone to higher summer temperatures than some downstream sections of the CSC study area.

  • Large warm-water fish populations may be a significant competition threat to any salmonids in the lake; current fish populations in the lake are unknown but warm water species numbers are thought to be low.
  • The current lake discharge presents a barrier to fish passage because of its culverted nature and the free drop at the downstream end. Reed College anticipates replacing this structure with a new channel designed to provide salmonid habitat and passage in 2001/2002, as funding permits. The design is currently in process.

This reach is largely in institutional ownership. Habitat values on this reach are high for upland and riparian adapted species, but only moderate for fish. Replacement of the Reed Lake outflow will create dynamic conditions for salmonids and conditions should be monitored to determine the impacts of these changes on general fish conditions. Some opportunities may exist on this reach for spring restoration.

TABLE 30 - PROJECT LIST by REACH

Reach 7 ? Reed Canyon Reach

7-1 Restore Lower Canyon ? restore protected riparian zone on 500 ft of lower canyon.
7-2 Reconstruct Reed Lake Outlet ? reconstruct lake outlet to permit fish passage.
7-3 Protect Reed Springs ? establish minimum buffers around Reed Canyon springs.
7-4 Amphibian & Reptile Plan ? study populations and develop a management plan.
7-5 Dredge Reed Lake ? dredge sediments to improve fish habitat
7-6 Remove Canyon Invasives ? remove invasives throughout Reed Canyon.
7-7 Purchase Upland Parcels ? acquire vacant parcel above Reed Springs.

V. Restoration Assessment

V.1.7 Reach 7 ? Reed Canyon Reach

Seven projects were identified for this reach, ranging from less than $1000 to $250,000 in capital cost. Six of these projects would require participation of the institutional landowner (Reed College). The habitat on this reach is the highest in overall quality in the basin, particularly for upland and riparian species; however, the potential for viable salmonid habitat above Reed Lake would appear to be limited. Acquisition on this reach would have little impact on in-stream conditions. One substantial project on this reach (project 7-2, replace Reed Lake outlet) is currently in the planning stages and may be funded by alumni contributions. Costs were not estimated for project 7-3 (dredge Reed Lake) because the feasibility of this option has not been studied.