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Temperature

Similar to flow, temperatures in the Umatilla River below McKay Creek are also seasonally limiting, reaching in excess of 28ْC at Three Mile Dam (RM 4) in August of 1998 (Boyd et al. 1999). As water temperatures increase in summer months, more of the subbasin becomes temperature limiting to fish

In the summer of 1998, temperature increased from RM 47 to RM 5 by nearly 5 degrees Celsius during the temperature-limited period. Temperatures rise above the 21ºC threshold for increasingly longer times progressively downstream. At RM 47 the river stayed below the threshold, due to cool water input from McKay Creek. Downstream at RM 42, the river was above the threshold value from early July to early August. By RM 5, the Umatilla River rose above the threshold before monitoring began in June until mid-September. The temperature limitations come from a variety of impacts including high width-to-depth ratios, low percent riparian shading, limited interaction between the stream channel and the flood plain during high flow recharge periods and reduced flow volume (Purser 1994).



In addition to problems in the mainstem Umatilla River, Birch Creek, East Birch Creek, North Fork McKay Creek, West Birch Creek and Westgate Canyon are listed on the 1998 303(d) list for failing to meet the salmonid rearing criterion of 17.8 C (Boyd et. al 1999).

Water Quality (chemical)

The lower portion of the Umatilla subbasin is subject to the greatest amount of land use disturbance. Habitat degradation resulting from urban runoff, pesticides and herbicides, excessive nutrient inputs, and a variety of other contributions are most prevalent throughout the lower 51 river miles of the Umatilla. Nitrates show up as a possible problem in the lower Umatilla subwatershed, ranging from 0.60-6.10 mg/l at Umatilla RM 2.1 (Purser 1994). Exceedingly high (> 0.4 mg/L) levels of ammonia have been recorded in Butter Creek (Purser 1994), further reducing habitat use by key species. A “threshold” value of 0.1 mg/L total phosphorous (California cold freshwater habitat criteria) is exceeded in the lower mainstem and McKay Creeks (Purser, 1994). Furthermore, the Butter Creek subwatershed has been documented as having water quality problems related to agricultural chemicals (Purser 1994). Very high levels of coliform bacteria are recorded at the Umatilla River at Reith Station (just below the Pendleton Sewage Plant).


Passage


Key fish species in the Umatilla subbasin may encounter a combination of passage impediments when migrating up the lower mainstem Umatilla River, McKay Creek or other tributaries in this portion of the subbasin. In addition to thermal barriers, a number of structural barriers exist downstream of McKay (Table 36). These impediments may severely limit fish movements.
Table 36. Known Fish Passage Barriers below McKay (A. Sexton, CTUIR, personal communication, February, 2001)

STREAM

RIVER MILE

BARRIER TYPE

COMPOSI-TION

STEP HEIGHT (m)

DEGREE

RECOM-MENDED ACTION

Umatilla River

1.5

Channel Modification

Concrete

0.7

Partial

Modify

Umatilla River

2.4

Irrigation Dam

Concrete

1.0

Partial

Modify


Umatilla River

28.8

Feed Canal Irrigation Dam

Concrete

1.5

Partial

Modify / Remove

Umatilla River

49.0

Vacated Irrigation Dam

Unknown

1.2

Unknown

Remove

Jungle/Windy Spring

0.1

Culvert

Steel

0.15

Partial

Modify

McKay Creek

6.0

Earthen Dam

Earth/Concrete

40

Complete

Leave

Butter Creek

7.9

Flash Boards

Wood

2.3

Complete

Modify

Butter Creek

27.2


Irrigation Dam

Concrete

1.4

Complete

Modify

Butter Creek

43.0

Irrigation Dam

Concrete

1.2

Complete

Modify

Johnson Creek Tributary of Butter Creek

0.3

Culvert

Wood

0.8

Partial

Modify

Stewart Creek

0.6

Bridge

Concrete

0.4

Partial

Modify

Birch Creek

0.5

Pipe Casing

Concrete

1.4

Partial

Modify

Birch Creek

5.0

Irrigation Dam

Concrete


1.2

Partial

Modify/ Remove

Birch Creek

10.0

Irrigation Dam

Concrete

1.0

Partial

Modify

Birch Creek

15.0

Irrigation Dam

Concrete

1.0

Partial

Remove/ Modify

W. Birch Creek

3.8

Bridge

Concrete

1.2

Partial

Modify

W. Birch Creek

3.5

Irrigation Dam

Concrete

2.1

Partial

Modify

W. Birch Creek

5.5

Irrigation Dam

Concrete

1.4

Partial


Modify

W. Birch Creek

8.5

Irrigation Dam

Concrete

Unknown

Partial

Modify/ Remove

W. Birch Creek

9.0

Irrigation Dam

Concrete

Unknown

Partial

Modify/ Remove

W. Birch Creek

?

Culvert

Steel

Unknown

Unknown

Unknown

E. Birch Creek

9.0

Irrigation Dam

Concrete

0.8

Partial

Modify/ Remove

Stewart Creek

0.6

Bridge

Concrete

0.4

Partial

Modify



Channel Conditions

The geomorphological assessment of channels at a basin-wide level currently represents a data gap. Seventy-nine of the lower 90 miles of the mainstem Umatilla River, from the mouth to the forks, were determined to have undergone human-caused channel alteration, restriction and/or diking (Close 1999). Extensive channel modification has occurred throughout this portion of the subbasin for more than a century. Railroad surveys from 1913 of lower Birch Creek indicated that portions had already been channelized (Nagle 1998). Aerial photos taken by the USDA in 1939 revealed that some tributaries within the Umatilla subbasin were channelized prior to 1939 (Nagle 1998). Nagle (1998) speculates that these stream manipulations occurred before the advent of heavy equipment. However, Harper et al. (1948) indicates that steam-powered tractors were available in Umatilla County in 1904 and 1905, caterpillar-type gasoline-powered tractors were introduced from 1907 to 1909, and diesel oil-burning caterpillar type tractors could be purchased in 1932. Perhaps, early farmers used such machinery to channelize streams in the lower Umatilla subbasin. An early account by a farm wife from Butter Creek mentioned that her husband was straightening the creek prior to 1920 (Nagle 1998).

Instream Habitat Diversity


The diversity of instream habitat in the lower portion of the Umatilla subbasin is ranked as poor-fair. Over the past several years, the CTUIR and ODFW have collected biological and physical data in an ongoing effort to monitor and evaluate natural salmonid production in the Umatilla subbasin. Included in this data are a number of variables, which are used to evaluate habitat complexity as it relates to key species use. This information is presented in Table 31 and Table 32, which include evaluation of habitat in various portions of the basin.

Instream habitat diversity in the lower subbasin, which may be coarsely evaluated using the parameters ‘percent pool area’, ‘width:depth’ and ‘woody debris’, is variable (Table 31). During 1995-1996 surveys of mainstem river miles 0-56, CTUIR found the percentage of the reach comprised of pools was good. The lack of instream large woody debris, which received a ‘poor’ rating, was attributed to the sparse amount of streamside vegetation throughout the reach, and throughout the majority of upstream reaches. Analyses of habitat parameters in the Birch Creek system (refer to Table 32) suggest that the streams are lacking habitat diversity as indicated by the low number of in-channel wood, low pool area and lack of complex pools. Very few of the variables assessed by ODFW were considered “desirable,” while most were classified as undesirable.

Because habitat diversity is intrinsically linked to other factors, such as stream sinuosity, floodplain connectivity and input of organic material, it is not surprising to see a relatively homogenized aquatic ecosystem throughout these lower reaches. Of primary concern is the lack of hydraulically active woody debris. The role of large wood in lower gradient areas is important for gravel bar stabilization and vegetation establishment. Woody material also provides off-channel and back channel areas where juvenile fish rearing occurs (Webster 1998). Based on historical accounts, habitat heterogeneity in lower portions of the Umatilla may have once been considered high, due to larger volumes of in-channel wood. Wilson Price Hunt’s overland trip to Astoria, Oregon passed down the Umatilla River in January 1812 and noted while descending the Umatilla River that “beaver must be common because many places are full of their dams.” Hunt’s trip proceeded from just below Pendleton down the Umatilla River to the Columbia River (Rollins 1935). Beaver still occupied nearly every body of water when whites showed up in the Blue Mountains in 1811, but thirty years later they had all but vanished (Langston, 1995).

The absence of beaver in the lower Umatilla subbasin is evident. The hydrologic retention in the basin is short in duration, a condition that would likely be more prolonged with the presence of instream beaver dams (Langston 1995). The lack of backwater areas throughout the lower reaches indicates a noticeable absence of flow shunting structures. The result is fewer rearing areas, reduced nutrient dispersal, and subsequent reductions in riparian zone succession (Langston 1995).

The areas downstream of the McKay Creek portion of the subbasin, East and West Forks of Birch creeks, and North Fork McKay Creek are listed on the 303(d) list for habitat modification. The listing is based on comparison of in-field measurement of habitat elements (pool frequency, pool quality, pieces of wood per 100 meters, width/depth ratio) to the ODFW habitat benchmarks (Oregon Department of Environmental Quality 2000).


Sedimentation


While background sedimentation levels in the lower subbasin have likely always been high, current rates in the lower subbasin are deemed excessive. Composite samples of turbidity, collected at various stations during the winter of 1997-1998, show that Tutuilla, Birch, and five sites on the Umatilla River mainstem exceeded standards on numerous occasions (Oregon Department of Environmental Quality 2000). The West Fork Birch Creek, North Fork McKay Creek and the mainstem Umatilla River in this section are on the 1998 303(d) list for sedimentation. The primary sources of sediment are from raw and eroding streambanks, unstable stream channels, and upland sources (T. Bailey, Oregon Department of Fish and Wildlife, personal communication, February 2001).

Riparian Condition

Lack of a sufficiently functioning riparian corridor, most notably throughout lower portions of the mainstem, affects instream temperatures and limits salmonid abundance and distribution (Contor et al. 1997). Riparian areas in poor condition are numerous. According to ODFW 70% of the Umatilla River tributaries need riparian improvement (Confederated Tribes of the Umatilla Indian Reservation and Oregon Department of Fish and Wildlife 1990).

The lower ten miles of the Butter Creek Drainage are almost devoid of woody riparian vegetation (Nagle 1998). Pioneer accounts mention that no trees existed along the creek where the Oregon Trail crossed it, but plenty of willow that could be used for fuel (Nagle 1998). And while the upper portion of the North Fork of Butter Creek has deeply incised channels, General Land Office survey records for Umatilla County mention that historically, some riparian trees and a number of springs occurred in this locality (Nagle 1998).

Although riparian shading throughout the wider sections of the Umatilla River is generally low, it has never entirely ameliorated mainstem temperatures (S. O’Daniel, Confederated Tribes of the Umatilla Indian Reservation, personal communication, February 2001). Many small springs, seeps, and hyporheic groundwater enter the surface flow, providing thermal refuges for salmonids during portions of the year (Confederated Tribes of the Umatilla Indian Reservation 1994).

The thermal refugia created by groundwater is not, however, considered a surrogate for the degraded riparian corridor bordering the lower 51 miles of the Umatilla River. Grazing, among other land uses, has had major impacts on riparian vegetation throughout the basin. Grazing intensity within riparian and floodplain areas has resulted in loss of surface cover, causing increased soil wash and wind erosion (Shelford and Hanson 1947).

Because much of the native vegetation bordering streams along the lower subbasin also borders agricultural ground, riparian areas commonly have been converted to cultivation. Indications are strong that Wildhorse, Tutuilla, McKay and Butter Creeks along with the lower Umatilla River contribute the major portion of suspended sediment to the Umatilla River (Purser, 1994). This is thought to result from soil left bare in grain farming operations or through overgrazing, streambanks denuded of vegetation for the purpose of agriculture or range management, and the lack of opportunity (due to channelization) for floodwater to spread over the floodplain and drop sediment (Purser, 1994).


McKay to Meacham


This reach extends for approximately 28 river miles upstream from McKay Creek. It includes the City of Pendleton and the Umatilla Indian Reservation. Two of the primary tributaries of the Umatilla River, Meacham Creek and Wildhorse Creek, enter the river in this reach. The lower portion of this reach is used solely for migration and overwintering, with steelhead spawning occurring above RM 65 (Contor et al. 1996). The Umatilla River between Meacham and McKay Creeks is outside of the influences of the Umatilla Basin Project and has no target instream values set for the reach. The river maintains relatively constant flow through this reach with no major diversions for irrigation. The largest water withdrawal comes from the City of Pendleton, which has 10.5 cfs water rights. The City also has a series of infiltration galleries that lie in the alluvium from about half a mile downstream of Thorn Hollow to just above Squaw Creek.

Flow


Flow continues to be a problem in this section of the mainstem Umatilla River. While the Umatilla River between McKay and Meacham Creeks generally meets instream flow recommendations () from November through June (Figure 38), flows are documented as being as much as 130 cfs below recommended levels during summer months (Table 38; U.S. Geological Survey data). Whether the Umatilla River can regularly meet 130 cfs during the summer, given that little flow reduction occurs in this reach, is debatable. Only during high flow years was the Umatilla River above the recommended flow during the summer months.

Table 37. Instream Flow Recommendations (CTUIR 1999; OWRD 1988) for the Umatilla River Upstream of McKay Creek.

Agency


Oct

Nov

Dec

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sept

CTUIR

200

240

310

310

430

500

500

490

270

200

180

180

OWRD/ODFW

200

200

200

200


240

240

240

240

200

100

60

60

Summer flow in the mid-Umatilla River relies heavily on the portion of the basin above Meacham Creek, with losses from streamside irrigation, seepage and evaporation often exceeding local inflows (Towle 1935). The portion of the Umatilla River above Meacham Creek represents about 20% of the area above Pendleton, but in instances, the flow above Meacham Creek was 200% greater than that at Pendleton during the summer months. During flood events, the Meacham and Wildhorse watersheds contribute a larger part to the volume at Pendleton. During smaller floods, 45% of the water reaching Pendleton originates upstream of Meacham Creek, while during larger events the percentage decreases and may be as low as 30% during the highest flows (Towle 1935). This implies that one of the key areas for maintaining sufficient habitat-sustaining summer flow in the Umatilla River above McKay Creek lies in the watershed above Meacham Creek.



Figure 38. Mean Monthly Discharge vs. Instream Flow Recommendations between Meacham and McKay Creeks
Table 38. Low-flow statistics for the Umatilla River between Meacham and McKay Creeks (Oregon Department of Environmental Quality 2000).

Return

Period


Umatilla R. upstream

of McKay Creek

Umatilla River at

Pendleton

Umatilla River

Near Cayuse

1-Day

7-Day

14-Day

1-Day

7-Day

14-Day

1-Day

7-Day

14-Day

1-year

33.5

39.8

44.8

64.4

69.2

72.5

56.7

57.2

58.1

2-year

17.5

18.7

19.4

25.7

28.8


30.8

40.5

41.5

42.0

5-year

14.2

16.8

17.7

20.7

23.5

24.9

38.4

38.8

39.2

10-year

13.0

16.2

17.3

18.9

21.6

22.6

37.4

37.7

38.2

25-year

N/A

N/A

N/A

17.4

20.1


20.6

N/A

N/A

N/A

50-year

N/A

N/A

N/A

16.5

19.2

19.4

N/A

N/A

N/A

100-year

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A



Instream Temperatures

The Oregon Department of Environmental Quality (1999) reported results of thermographs placed in the Umatilla River at RMs 59.5 and 67.5. The instrument at RM 67.5 recorded slightly higher temperatures than the one at RM 59.5, which broke the trend of warming in the downstream direction. The probe located at RM 78.8 was limited from June to August.

The entire Wildhorse Creek drainage regularly experiences excessive summertime stream temperatures. Headwaters often exceed 20°C for long periods in the summer, while lower Wildhorse Creek can often experience stream temperatures exceeding 30°C (Boyd 1999). Unfortunately, Wildhorse Creek has the distinction of regularly producing some of the highest summertime stream temperatures observed in Oregon. Wildhorse Creek drains the cultivated foothills of the Blue Mountains and enters the Umatilla River at Pendleton. Wildhorse Creek produces considerable run-off, particularly in years of deep snow or heavy winter rains (Bureau of Reclamation 1954).

The confluence of the Umatilla River with Meacham Creek represents an area of thermal mixing. Meacham Creek adds warmer water to the mainstem Umatilla River partly from the presence of the Union Pacific Railroad corridor throughout its length. The railroad has had a major impact on the stream zone through shade reduction and channel simplification (Umatilla National Forest 2000).

Buckaroo Creek, Squaw Creek, Wildhorse Creek and the Umatilla River between McKay Creek and Meacham Creek are listed on the 1998 303(d) list for temperature for not meeting salmonid rearing criterion of 17.8°C (Boyd et. al 1999). These areas are suspected thermal barriers to migration


Water Quality (chemical)


Either one or both of the state water quality criteria for fecal coliform bacteria and enterococcus are frequently exceeded for the Umatilla River below the Umatilla Indian Reservation and parts of Wildhorse Creek (Purser, 1994). Very high levels of coliform bacteria are recorded at the Umatilla River at Reith Station (just below the Pendleton Sewage Plant). Sources include municipal wastewater treatment facilities, individual septic/drain field systems, confined animal feeding areas, soil from surface or streambank/bed erosion (Purser, 1999). A “threshold” value of 0.1 mg/L total phosphorous (California cold freshwater habitat criterion) is exceeded for the Umatilla River from below Gibbon to the mouth of the Umatilla River and in Wildhorse Creek (Purser, 1994).

Passage


In addition to thermal barriers, a number of structural barriers inhibit movement in the McKay to Meacham portion of the subbasin. These barriers are summarized in Table 39.

Channel Conditions

In the mid and lower portions of the Umatilla subbasin, entrenched channels are found in the valley bottoms, which are characterized by deep alluvial deposits. Entrenched streams in this area include, among others, Wildhorse and Tutuilla Creeks (Nagle 1998). These entrenchment levels are less prominent in gravel and cobble bedded streams, such as in Meacham and McKay Creeks, because these systems are more resistant to incisions and tend to exhibit hydrologic responses by widening (Nagle 1998; T. Shaw, Confederated Tribes of the Umatilla Indian Reservation, personal communication, February 2001). Historical accounts indicate that most entrenchment processes began around the turn of the century, immediately after the elimination of beaver populations. These periods also coincided with the highest livestock densities (Nagle 1998).

Table 39. Known Fish Passage Barriers from McKay to Meacham (A. Sexton, CTUIR, personal communication, February, 2001))


STREAM

RIVER MILE

BARRIER TYPE

COMPOSI-TION

STEP HEIGHT (m)

DEGREE

RECOM-MENDED ACTION

Wildhorse Creek

0.1

Vacated Irrigation Dam

Concrete

0.7

Partial

Modify

Wildhorse Creek

18.8

Road Bridge Structure

Concrete

1.0

Partial

Modify

Greasewood Creek

0.4

Irrigated Dam

Concrete

0.6

Partial

Modify

Mission Creek


0.9

Channel Shift

Bedrock

0.5

Partial

Modify

Mission Creek

3.3

Bridge/Culvert

Steel

0.7

Partial

Modify

Coonskin Creek

0.3

Road Bridge

Concrete

0.5

Partial

Modify

Coonskin Creek

0.9

Water Pipe Protection

Concrete

1.1

Partial

Modify

Whitman Springs

0.1

Culvert

Steel

0.5

Complete

Modify

Red Elk Canyon Creek

0.2

Culvert


Steel

0.8

Partial

Modify

Un-Named Tributary at Minthorn effluent

0.1

Culvert

Steel

0.5

Partial

Modify

Stream channelization is also considered to be partially responsible for reducing natural stream channel morphology. Channel diking and levee construction to protect adjacent roads is common throughout portions of the mainstem Umatilla River and Wildhorse Creek (Shaw and Sexton 2000). Channel migration is further limited in Wildhorse Creek and the mainstem Umatilla River due to abandoned or active railroads, which have confined stream channels along the majority of their lengths (Shaw and Sexton 2000).



Instream Habitat Diversity

Contor et. al (1994) found that the abundance and volume of woody debris in this portion of the subbasin were at undesirable levels in riparian and channel inventory locations (Table 31). Portions of riparian areas in the upper reaches of mainstem Buckaroo Creek lack sufficient levels of downed woody debris and coarse woody debris complexes to function properly in terms of flow energy dissipation and sediment routing. Channel widening is occurring in specific areas as sediment, mainly in the form of bed load, overwhelms available stream energy and is deposited throughout the active channel profile. These deposits remain unstable and move with each bankfull event. Streambanks are not being built which decreases opportunities for riparian vegetation establishment (Webster 2000).

Several tributaries to McKay Creek, such as Bell Cow, Calamity, Darr, Lost Pin, and Rail Creeks are listed on the 303(d) list for habitat modification. Coonskin, Mission, and Moonshine Creeks, are also listed for habitat modification. The listing is based on comparison of in-the-field measurements of habitat elements (pool frequency, pool quality, pieces of wood per 100 meters, width/depth ratio) to the ODFW habitat benchmarks (Oregon Department of Environmental Quality 2000).


Sedimentation


One of the sediment-impaired stream segments that significantly deviated from the target standard was Wildhorse Creek (at its confluence with the Umatilla River), which had a peak turbidity value of over 5,000 Nephelometric Turbidity Units (NTU’s) measured on April 23, 1997. Wildhorse Creek turbidity is mainly due to later winter and early spring runoff events. At present the Wildhorse Creek Drainage is the most intensively cropped tributary to the Umatilla River, and it appears to be the largest sediment producing system within the subbasin (Nagle 1998). Coonskin Creek, Cottonwood Creek, Line Creek, Mission Creek, Moonshine Creek and the Umatilla River in the Meacham Creek to McKay Creek reach are listed on the 1998 303(d) list for sediment.
Habitat surveys conducted by CTUIR in June 1994 found that fine sediments comprised 20% of the streambed substrate and that 12% of the streambank length was eroding in this reach (Contor et al. 1994).

Riparian Condition


Below Meacham Creek, the Umatilla River is wider and flows through cultivated lands, with minimal shade provided by shrubs, deciduous trees and grasses (Confederated Tribes of the Umatilla Indian Reservation and Oregon Department of Fish and Wildlife 1990). These areas have moderate-low quality salmonid habitat.

Above Meacham

Flow


Flow is not cited in main documents as a problem in this portion of the subbasin. Five water diversions were documented at private residences (Contor et al. 1995). The impact of these diversions on aquatic habitat has not been documented.

Temperature

The North Fork and South Fork Umatilla River, Shimmiehorn Creek and North Fork Meacham Creek are listed on the 1998 303(d) list for temperature not meeting the Oregon Bull Trout Criterion (10 C). East Fork Meacham Creek and Meacham Creek are listed on the 1998 303(d) for temperature not meeting the salmonid rearing temperature of 17.8 (Boyd et. al 1999). None of the stream reaches for which full season data were available in the above Meacham Creek area met PACFISH or Oregon state standards for water temperature. Temperatures were generally better in the North Fork than in the South Fork Umatilla River. Temperatures in mainstem Meacham Creek exceeded PACFISH maxima by wide margins in all years of record, exceeding lethal limits for salmonids at times (Umatilla National Forest 2000). Thermal loading from two hot springs at Bingham and at Buck Creek may be a factor in warming the lower South Fork (Umatilla National Forest 2000), which, at its confluence with the Umatilla, may increase mainstem temperatures to as much as 18ºC.


Water Quality (chemical)


The chemical constituents of streams and rivers above the confluence of Meacham Creek are, for the most part, within the natural range of conditions. Oregon Department of Environmental Quality (2000) identified aquatic weeds or algae as an impairment to mainstem water quality from the confluence of Wildhorse to the Forks, which includes this upper river reach. Potential nutrient additions from rural areas may cause localized problems.

Passage


Known passage problems in and above Meacham Creek are summarized in Table 40.
Table 40. Known Fish Passage Barriers In and Above Meacham (A. Sexton, CTUIR, personal communication, February, 2001)


STREAM

RIVER MILE

BARRIER TYPE

COMPOSI-TION

STEP HEIGHT (m)

DEGREE

RECOM-MENDED ACTION

Un-Named Tributary at RM 1.5 of SF Umatilla River

0.1

Culvert

Steel

0.5

Complete

Modify

Camp Creek


.25

Vacated Irrigation Dam

Concrete

1.3

Partial

Remove

Un-Named Tributary at Umatilla River RM 81.2

0.1

Culvert

Steel

0.6

Partial

Modify

Twomile Creek

1.25

Culvert

Steel

Unknown

Unknown

Modify



Channel Conditions

The channel from headwaters to Meacham Creek was classified as constrained during habitat surveys conducted by CTUIR in July-August 1995 (Contor et al. 1995). This channel however, is a “B-type” channel (Rosgen methodology), which is considered to be naturally constrained. Constrained waterways have reduced off-channel habitat, a determinant of smolt production. Only nine percent of the bank length had established undercutting, potentially valuable to fish, and seven percent of bank length was actively eroding (Contor et. al 1995).

Most tributaries upstream of and including Meacham Creek have been heavily impacted by adjacent roads, dikes, campgrounds, and trails which have lowered sinuosity and decreased shade, large wood and pools (Umatilla National Forest 2000). The Union Pacific Railroad corridor along Meacham Creek, for example, has significantly reduced channel complexity. Streams in roadless areas or wilderness areas have experienced few direct impacts (Umatilla National Forest 2000).



Instream Habitat Diversity


The Upper Umatilla River and Boston Canyon, Meacham, Mill, North Fork Meacham and Line Creeks are listed on the 303(d) list for habitat modification. The listing is based on comparison of in-field measurement of habitat elements (pool frequency, pool quality, pieces of wood per 100 meters, width/depth ratio) to the ODFW habitat benchmarks (ODEQ 2000).

Eighteen out of 19 stream reaches surveyed with PACFISH protocols met standards for large woody debris minimums of 20 pieces per mile in the above Meacham portion of the subbasin. Additional surveys by ODFW and CTUIR found more woody debris in the North and South Forks of the Umatilla River than in Meacham Creek. Logging in riparian areas, roads next to streams and intensive grazing practices, which slow down riparian tree regeneration, have reduced large woody debris inputs in to Meacham Creek and the upper Umatilla River headwaters (Umatilla National Forest 2000). CTUIR and ODFW surveys found that Camp Creek and upper Meacham Creek had the best overall fish cover—including bank undercutting, large boulders and large woody debris. Surveys in the North and South Fork Umatilla River found relatively high pool frequency in most subwatersheds. This is at least partly explained by the presence of constructed pools (Umatilla National Forest 2000).

According to Shaw (CTUIR, personal communication, February 2001), beaver populations appear to be increasing throughout the upper Umatilla River subbasin. Beavers now occur within nearly all of CTUIR’s Habitat Enhancement Project Areas. However, landowners frequently do not realize the potential benefits that beavers provide and continue to destroy the animals.

Woody debris counts were low in the mainstem Umatilla River channel from headwaters to Meacham Creek. Only 1.5 pieces of wood per 100 meters met criteria and volume was very low. High flows had deposited the majority of the wood outside of the wetted channel where it was of little value to fish. As a result, instream wood complexity ratings pertaining to fish habitat ranked very low.


Sedimentation


Meacham Creek and its tributary Boston Canyon Creek, and the Umatilla River to the forks are on the 1998 303(d) list for sedimentation. ODFW and CTUIR habitat surveys found that 18 subwatersheds in the Meacham Creek drainage had fine sediment as the dominant substrate. Out of 42 subwatersheds sampled in the North and South Forks of the Umatilla River and Meacham Creek only two exceeded 35% embeddedness (Umatilla National Forest 2000). Surveys found that the Meacham Creek watershed has many reaches containing unsuitable rearing substrate. In 30 out of 50 reaches surveyed by the Umatilla National Forest; ODFW, and CTUIR above Meacham Creek, substrate appeared to be a good quality component of spawning habitat (Umatilla National Forest 2000).

Riparian Condition

Through much of the upper Umatilla subbasin, riparian vegetation is not a limiting factor. However, significant areas are degraded (Tim Bailey, Oregon Department of Fish and Wildlife personal communication February 2000). The mainstem Umatilla, between the Forks to Meacham Creek receives moderate rates of shading due to a mixture of deciduous trees and conifers. Patches of high to moderate-high quality habitat exist in these areas and are used by salmonids for spawning and rearing.

The North and South Forks of the mainstem Umatilla River are well shaded by conifer canopies. The North Fork Umatilla River and Ryan Creek had the highest levels of canopy cover upstream of and including Meacham Creek's portion of the basin, while the mainstem Umatilla River between the Forks and Meacham Creek had the lowest canopy cover. Low values were also found on the South Fork Umatilla River between Thomas Creek and the North Fork confluence (Umatilla National Forest 2000). The Umatilla National Forest (2000) found an inverse relationship between roads and canopy cover, with the highest canopy cover on unroaded streams. Habitat inventories and instream temperature monitoring of the Meacham Creek system show temperature, pool area, stream width-to-depth ratio, shading, large woody debris volume and amounts of fine sediment to be at less than desirable levels (Table 31and Table 32). From the Forks to Meacham Creek, low tree densities were recorded in riparian transects. Only three trees per 100m met minimum size criteria and only 15% were 30cm diameter at breast height (dbh) or more. Canopy closure was estimated at 30% and open sky was 50%--both ranked as poor (Contor et. al 1995).


Habitat Quality – Wildlife

Forest


Approximately 21% of the subbasin consists of forested habitat (Figure 17). The remaining area (79%) historically consisted of shrub and grassland habitats, but more recently has been converted to agricultural lands interspersed with shrublands. Forested habitat occurs primarily in the southern portion of the subbasin at mid and high elevations (Figure 17). In the mid-lower elevations, tree dominated areas primarily consist of cottonwood galleries and pine stringers along streams. The three primary forest vegetative groups are identified below as well as key habitat components.

Dry Forest

The dry forest group occurs predominately at the mid and lower elevations and on southerly aspects in the forested zone. Dry forest types are generally limited by low water availability and are often subject to drought. This group primarily consists of ponderosa pine as the cover type, but Douglas fir is also common at the upper elevations and moister sites (Quigley and Arbelbide 1997).

Timber harvest and fire suppression have reduced the prevalence of the dry forest group in the region (Quigley and Arbelbide 1997). Since ponderosa pine is a valuable timber species, large mature stands were among the first to be harvested after European settlement (U. S. Forest Service 1990). Fire suppression further reduced the extent of ponderosa pine in the subbasin. The thick bark of ponderosa pine allows it to withstand ground fires better than the thin-barked true firs. In areas with a short fire return interval, firs never had an opportunity to become established. Fire suppression allows the shade-tolerant forest fir species time to establish in the understory of ponderosa pine forest. In the continued absence of fire these species eventually become dominant when the canopy becomes dense enough that the shade-intolerant ponderosa pine seedlings cannot survive (Johnson 1994). Henjum et al. (1994) reported that remaining old growth ponderosa pine in the region has been reduced 75-80% and that most of the loss came from logging between 1936 and the mid-1960s. Flammulated owl, pygmy nuthatch, and white-headed woodpecker are dependent on late seral ponderosa pine forests (Csuti et al. 1997). Populations of these species have declined with the ponderosa pine forests of the subbasin.


Moist Forest


The moist forest group occurs primarily at mid to upper elevations and on all aspects in transitional areas between drier, lower elevation forests and higher elevation colder forests. This group primarily consists of grand fir and mixed conifer cover types. Mixed conifer types can include a variety of species including grand fir, Englemann spruce (Picea engelmannii), lodgepole pine (Pinus contorta), Douglas fir, western larch (Larix oddidentalis), and ponderosa pine. Some of the dry forest cover types occur in the moist forest group as well (Quigley and Arbelbide 1997).

The aerial extent of mixed conifer forests in the Blue Mountains has increased since European settlement, primarily due to their establishment in areas dominated by seral ponderosa pine under natural fire return intervals (Quigley and Arbelbide 1997). These forests are primarily comprised of Douglas fir and grand fir but also include western larch, Englemann spruce, and sub-alpine fir (Abis lasicocarpa) (Clarke and Bryce 1997). The expansion of this cover type has not resulted in healthy populations of the wildlife species dependent on mixed conifer cover types. Fire suppression has resulted in dense multi-storied forests of uniform age. These stands exhibit a higher degree of susceptibility to forest insects and disease and low suitability to species like the MacGillivray’s warbler that prosper in uneven canopied forests (Johnson 1994; Csuti et al. 1997).



Cold Forest

The cold forest group occurs at the highest elevations and/or on north facing slopes. Cold forests are generally limited by a short growing season and by low moisture availability on some sites. This group consists of spruce fir cover types including subalpine fir, Englemann spruce, and lodgepole pine. There is some overlap in species composition between the cold forest types and the moist forest group. Due to the remote location of the cold forest habitat type, little loss to agricultural or urban development has occurred in the region. Fire suppression has resulted in a significant increase in the extent of mid seral shade tolerant species in this forest group (Quigley and Arbelbide 1997).

Grass and Scrubland

Historically, the majority of the subbasin was covered primarily by shrub steppe and grassland ecosystems. In the driest sections of the subbasin, big sagebrush ( Artemesia tridentata), bluebunch wheatgrass (Agropyron spiciatum) and Sandberg’s bluegrass (Poa sandbergi) were the dominant vegetation types. Areas that received slightly more precipitation were historically dominated by Idaho fescue (Festuca Idahoensis) (Clarke and Bryce 1997). Approximately 65% of the historic grass and shrublands of the Umatilla/Willow subbasin has been converted to agricultural cropland (Kagan et al. 2000) (Table 41). Most of the remnant shrub steppe ecosystems in the region occur on shallow soils or near rock outcroppings where farming is difficult. They are usually privately owned, relatively small fragments of land surrounded by agriculture (Dobler et al. 1996).

Remaining significant shrub steppe tracts include the undeveloped portion of the state of Oregon owned lands (known as the Boeing Agri-Industrial Company lands) and the contiguous Navy-owned property near Boardman (Boardman Bombing range) (Figure 18). Together these tracts form approximately 70,000 acres of steppe habitat and may serve as the only remaining source habitat for a number of declining wildlife species. However, from a landscape perspective these tracts are fragments of the former ecosystem. Introduced plant species, neighboring land activities, disease, predation, and low reproductive success of several wildlife species using these areas indicates that these tracts alone may not be capable of sustaining the shrub steppe ecosystem in the Umatilla/Willow subbasin. Other remaining shrub steppe habitats in the subbasin tend to be small isolated patches and in private ownership. Fragmentation reduces habitat value to wildlife species and increases susceptibility to noxious weeds and other outside influences.

Table 41. Habitat losses of lowland vegetation types within the Umatilla/Willow subbasin (Kagan et al. 2000)



Cover

Existing km2

Historic km2

Losses km2

% Habitat lost

Quaking Aspen

0

3.1

3.1

100%

Big Sagebrush Steppe

174.6

1226

105.4

86%

Bluebunch Wheatgrass

3730.4

6708.4

2978.0

44%

Riparian

44.6

330.3

285.7

87%

Idaho Fescue

1324.7


1723.6

398.9

23%

Western Juniper

0

73

73

100%

Tufted Hairgrass Wet Prairie

0

11.7

11.7

100%

Sandy Grassland

346.5

721.3

374.8

52%



Wetlands

Wetland habitats in the subbasin have decreased in the past 100 years, but it is difficult to quantify by how much. Many wetlands in agricultural areas have been filled to increase the amount of farmable acres (Quigley and Arbelbide 1997). Based on limited analysis conducted by the Confederated Tribes of the Umatilla Indian Reservation (1997), wetland losses in the upper Umatilla River range from 30 to 35%, while in the Umatilla/Echo Meadows complex losses are as high as 90%. Although wetlands are distributed throughout the Umatilla River subbasin, the majority are associated with riparian corridors and floodplains of the Umatilla River and its tributaries. These wetlands are primarily classified in the palustrine and riverine systems. The CTUIR analysis identified Minthorn Springs on the Umatilla Indian Reservation, a braided portion of the Umatilla River downstream of Pendleton, and the Echo/Umatilla Meadows complex as important wetland communities.

The Minthorn Springs area (RM 65) represents a riverine and palustrine (forested/emergent) wetland complex formed by the interface of the springs and the Umatilla River. According to NWI maps, the area contains approximately 19 acres of palustrine wetlands and 11 acres of riverine wetlands. Historically, the wetland received water inputs from intermittent tributaries. Input from those streams has now been reduced because upland farming has either eliminated or rechanneled the stream channels. Additionally, cottonwood forest stringers that once existed along the upland channels have either been reduced or completely removed, resulting in intermittent streams drying up earlier in the year. This area is important for water quality, quantity and fish and wildlife habitat (Confederated Tribes of the Umatilla Indian Reservation 1997).

The second focus area is located in the mid-lower river corridor west of Pendleton (RM 47). This area contains braided river channels and a cottonwood gallery with approximately eight acres of palustrine wetlands and five acres of riverine wetlands, according to NWI maps. This portion of the Umatilla River has been channelized for transportation routes (roads and railways), agricultural development, and diking. This focus area represents a habitat that was once much more common prior to these impacts, and still serves as a corridor for fish and wildlife (Confederated Tribes of the Umatilla Indian Reservation 1997).

The Echo-Umatilla Meadows complex is located lower in the Umatilla River corridor (between RM 18 and 24). This meadow complex results from the broadening of the river’s floodplain to nearly 10 times its upstream width. Examination of aerial photos reveals numerous side channels and oxbows that are now dry. These dry channels are generally within a mile of the existing high water mark. The area historically held palustrine emergent and open water wetlands that abated floods, trapped sediment, stored water, provided recharge to the river, and provided fish and wildlife habitat. Based on the results of the NWI map analysis, the area contains an estimated 862 acres of palustrine wetlands and 152 acres of riverine wetlands. Primary impacts to this area include conversion to farmland, channelization for agriculture, roadways, railways, diking, and urbanization (Confederated Tribes of the Umatilla Indian Reservation 1997).



Riparian


Riparian areas contain the most biologically diverse habitats in the subbasin because of their variety of structural features (including live and dead vegetation) and proximity to water bodies. This combination of habitat features provides a wide array of habitats that support more species than any other habitat (Quigley and Arbelbide 1997). Common deciduous trees and shrubs in riparian areas include cottonwood, alder, willow, and red-osier dogwood (U. S. Forest Service and Bureau of Land Management 2000).

Many riparian habitats in the subbasin have been converted to agriculture, degraded by livestock grazing, or cleared for timber harvest. Habitat has also been altered by 1) hydrological diversions and flood control structures (e.g., dams) which have resulted in reduced stream flows and reduced area of riparian habitat, loss of vertical stratification in riparian vegetation, and lack of recruitment of young cottonwoods, willows, and other riparian species, 2) streambank stabilization which narrows stream channels, reduces the flood zone, and reduces riparian vegetation (Altman and Holmes 2000a, 2000b)

Especially important is the virtual elimination of large cottonwood galleries that existed along most of the larger waterways. This habitat type, along with various subcanopy structural riparian classes associated with it, is critical for a number of riparian landbird species including Lewis’s woodpecker, Bullock’s oriole, yellow warbler, yellow-breasted chat, yellow-billed cuckoo, willow flycatcher, and lazuli bunting (Altman and Holmes 2000a, 2000b).

A GIS-based comparison of historic and current vegetation data shows losses to riparian communities of 87% in the lowland areas of the Umatilla/Willow subbasin. This is likely an underestimate since early documentation is limited to large contiguous riparian communities. The actual loss of riparian habitat in the subbasin is probably closer to 95% (Kagan et al. 2000).

Confederated Tribes of the Umatilla Indian Reservation (1997) analysis of the Echo/Umatilla Meadow area along the lower Umatilla River revealed that approximately 5,730 of 6,340 acres (90%) has been stranded or cut off from the current Umatilla River flood plain. The area’s numerous oxbows and dry channels used to be surrounded by wetland and riparian habitats.


Agriculture


The greatest change to the wildlife habitat in the Umatilla/Willow subbasin since historic times has been the introduction of agriculture. While human-induced impacts on vegetation began in the last century, the more recent availability of electric power and pivot-type sprinkler systems has resulted in the expansion of cropland along the Columbia River in Morrow County (Puchy and Marshall 1993). These areas support relatively limited wildlife populations but some species thrive here. Agricultural areas support many small birds and mammals, and their predators, including coyotes and red-tailed hawks (Csuti et al. 1997). Ring-necked pheasants are common in agricultural areas within the subbasin, but recently their numbers have decreased (Washington Department of Fish and Wildlife 2000b). Possible explanations for this decline include a reduction in shrub and tree cover surrounding fields and the negative effects of pesticides (Larsen and Nordstrom 1999). Deer and elk sometimes feed in agricultural lands, which occasionally leads to conflict between private landowners and wildlife management agencies. The CRP lands in the subbasin have increased dramatically in recent years. Wildlife habitat and native vegetation have increasingly become priorities of the program. A corresponding increase in deer populations in the subbasin has been attributed to this increase in available habitat.




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