Watershed Location

1
Elk River Watershed, Sixes River Basin, Curry
County, Oregon
Prepared by Kristin Mooney ES 492
Hydrologic Summary The drainage area measures
35,480m by 21,960m which is approximately 58678
acres. There is a total of 9 sub-basins within
the watershed that includes over 2,050
tributaries. Of those tributaries, over 1,000
are first order streams, and nearly 500 are
second order streams. The first order streams
are relatively warm compared to the tributaries.
(See Fig. 9) The Elk River Fish Hatchery is
located along the Elk River. Other users of the
watershed include miners, fishers and campers.
Watershed Location Elk River Watershed is
located in the Sixes River Basin in Curry County,
Oregon. (See Fig. 1)
General Geology There are Cretaceous sedimentary
rocks consisting of greywacke, conglomerates and
shale. Rocks from the Jurassic and Triassic
periods include mudstone, shale, siltstone,
greywacke, tuff, limestone and intrusives of
felsic to intermediate, quartz-rich, granite and
diorite. Recent deposits are terrace, pediment,
and lag gravels consisting of unconsolidated
gravel, cobble and boulders. (See figs. 4 5)
Fig. 1 Map of Oregon
Fig. 7
Fig. 9
Physiography The watershed ranges in elevation
from sea level to approximately 4,080 feet at the
summit of Iron Mountain. There are narrow,
forested, valleys with steeply sloping sides in
the upper portion of the basin. The remaining
portion of the basin is relatively flat. (See
Fig. 2) The lower portion of the watershed
receives 70-100 inches of precipitation per year
and the upper portion receives 100-180 inches per
year. (See Fig. 4) In 1930, European Beach grass
was introduced. In the lower portion of the
watershed, large log "drifts were removed for
agricultural development. This resulted in loss
of wetlands and reduction of riparian vegetation,
which is being overtaken by gorse and Himalayan
blackberry. (See Fig. 5)
Elk River
Fig. 8
Fig. 2
Fig. 3
http//memory.org/point.b/image/img_1277.jpg
Fig. 5

• Conclusions
• The watershed is located in southern oregon, in
  Curry county, along the coast.
• The Watershed ranges from high elevation to sea
  level.
• Like all watersheds, precipitation is a key
  factor.
• Soils are derived from mainly sedimentary
  bedrock.
• The main group of vegetation is Douglas Fir and
  Tan Oak.
• There are numerous tributaries off Elk River.

Fig. 6
Fig. 4
References Cited "Elk/Sixes River Watersheds."
currywatershed.org. The South Coast and Lower
Rogue Watershed Councils. 21 Mar 2007
lthttp//www.currywatersheds.org/watersheds.php?idl
nk_art15modpage_mastergt.