Watershed Location

The West Fork Millicoma River watershed is located in Western-Central Oregon, primarily in Coos county, and part in Douglas county. (See figure 1 & 2).

General GeologyGeneral Geology: summary of the types of bedrock and soils found in your watershedSoils: The soils at lower elevations are made of clay and sand. At high elevation the soil is fine loam.Geology: The five geologic units consist of , TY(Yamhill Formation ), Tt (Tyee Formation), Tss (Tuffaceous Siltstone and Sandstone), Tsr (Siletz River Volcanic) and Qal (Alluvial Deposits)

Hydrologic Summary

The West Fork Millicoma River occupies an area of 390,363,097.99785 square meters. Its length is ++++ and its width is +++++. It has a Watershed length/width ratio of +++. It has a total of 13 subbasins, with an average area of 30.07 square kilometers. The total number of stream segments in the West Fork Millicoma River is 3,337. The total number of first order stream segments is 1,679, with 775 second order stream segments. The first order stream frequency is 4.29.

i. Figures1. Watershed outlines and stream overlays

Conclusions

(1) The West Fork Millicoma contains a large portion of streams. Also the West Fork Millicoma contains many type of soils that change from the hill top to the floor.

(2) We discovered that the West Fork Millicoma is in a more secluded area with little road access.

West Fork Millicoma River WatershedCoos and Douglas Counties, Oregon

Prepared by:

Robert BoyerJade McCredy

ES 341

Douglas fir-western hemlock-grand fir, and mixed conifer and broadleaf deciduous are the primary vegetation in this watershed. Sitka spruce-western hemlock forest also covers a small portion. There is also a small harvested area in the South-East. The West Fork Millicoma ranges in elevation from 9.8 feet to 2,408 feet. The minimum slope is 86.4 decimal degrees, and the maximum slope is 234 decimal degrees. The precipitation ranges from 65-90 inches of rainfall a year.

West Coast Millicoma River

Figure 2: Watershed Counties

Legend

West Coast Millicoma River Watershed

Oregon

Figure 1: Watershed Location

Streams

West Fork Millicoma River Watershed

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Figure 10: Watershed Streams

0 4,900 9,800 14,700 19,6002,450Meters

0 4,900 9,800 14,700 19,6002,450Meters

Figure 7: Watershed DOQs

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Figure 9: Vegetation

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0 4,900 9,800 14,700 19,6002,450Meters

Vegetation

VEG_NAME

Douglas fir-western hemlock-grand fir forest

Mixed conifer and broadleaf deciduous forest

Recent timber harvest areas

Sitka spruce-western hemlock forest

®0 4,900 9,800 14,700 19,6002,450

Meters

Legend

West Fork Millicoma

Elevation

Value

High : 736

Low : 0

Figure 6: DEM

Legend

Soil Type

MUSYM

10C

12

13D

13E

13F

17B

24

30D

30E

33

34

37C

38F

40

41

42

44D

44E

46D

46E

46F

48

4D

4E

51D

51E

54D

56E

57

58F

62

63B

63C

63D

65

66D

75E

W

147F

148F

179E

195F

196E

197E

197F

198F

200F

212G

238F

253G

27G

2E

49F

49G

58G

0 4,900 9,800 14,700 19,6002,450Meters

Figure 4: Soil

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Legend

Bedrock Geology

Qal

Tsr

Tss

Tt

Ty

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0 4,900 9,800 14,700 19,6002,450Meters

Figure 3: Geology

Streams

Precipitation

RANGE

65

67

69

71

73

75

77

79

81

83

85

87

89

91

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0 4,900 9,800 14,700 19,6002,450Meters

Figure 8: Climate