Coast Fork Willamette Watershed
GIS Analysis and Mapping Pages
December, 2002
Base Maps:
The Coast Fork Willamette Watershed is located at the southern end of the Willamette River Basin. The headwaters of the Coast Fork feed the Willamette River which is the 13th largest river in the "lower Forty Eight" and provides approximately 15% of the annual discharge to the Columbia River.
The Coast Fork Willamette Watershed occupies 663.6 square miles, or 14.4% of Lane County.
Some day soon (geologically speaking), the Coast Fork will drain to the coast just southwest of Cottage Grove at Divide via Martin and Pass Creeks. These two creeks are separated by a 20' difference in elevation and 1000' in horizontal distance. In fact, during the late Cenozoic, the Umpqua River used to flow north into the Willamette via this route.
The emphasis of this study is on the Lower Coast Fork watershed, which is 139 sq. mi. in area.
This fifth field watershed is composed of five sixth field watersheds:
Located at the northern edge of the watershed, the Lower Coast Fork is nestled between the urban growth boudaries of Eugene and Springfield and Cottage Grove.
The watershed ranges in height from a minimum of 508' to maximum of 3366'. Creswell sits at 590'.
Significant mountains in the Lower Coast Fork watershed include:
Snow zone map.
In Oregon, it generally snows above 4200' and rains below 1500'. In the transition zone between these two, havoc is created when a cold front drops a bunch of snow which is followed by the Pineapple Express which pours rain on top of the snow causing it to melt quickly. Nearly 13% of the Lower CFW is in this transition zone, depicted here as icy blue:
Streams:
Ownership:
Zoning:
Preliminary crude detailed Zoning:
Here's an example of Rural Residential Zoning:
There's more on CFW page 2.
For more information, send a note to
jpreed@epud.net Copyright (c) 2002 October, 2002. This page is http://www.epud.net/~jpreed/cfw.htm
The highest portion of the watershed in the southeast.
Fifty percent of the watershed is between 508' and 773', dark green
50%-75% is between 773' and 1088', yellow.
75%-95% is between 1088' - 2166', orange.
The top 5% of the watershed is between 2166' - 3366', red.
Prune Hill which is 2690' tall.
Cougar Mountain, 2422'.
Spencers Butte, 2065'.
Mt Pisgah, 1528'.
Short Mountain, 1147'.
Seller Mountain, 1086'.
Bear Mountain, located just outside of the watershed boundary, is 3698' tall.
There are still some gaps in this data, (about 6,000 acres). The total watershed area is 88,970 acres.
Category Area(acres)
F1 25,649
F2 16,620
E4 12,207
E3 7,585
RR 7,297
E2 7,076
PR 1,915
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Total 78,349 acres or 88% of the watershed.
Jim Reed, Ph.D.
The HydroLogic Group
Mapping, GIS Analysis and Web page development
All rights reserved.