Green- Duwamish River Watershed

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Green-Duwamish River Watershed

• The Green River Watershed is the land area where
  rainwater drains to the Green-Duwamish River.

http//www.epa.gov/owow/showcase/duwamish/
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• The watershed includes Black River, Springbrook
  Creek, Mill Creek, Soos Creek, Jenkins and
  Covington Creeks, Newaukum Creek, Crisp Creek,
  and other tributaries.

http//dnr.metrokc.gov/wlr/watersheds/green.htm
http//wa.water.usgs.gov/realtime/htmls/green.html
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Green River Watershed Facts

• Watershed Size 492 square miles
• River Length 65 miles from Elliott Bay to Howard
  Hanson Dam
• Population Approx. 400,000
• Salmon Species Present Chinook, chum, coho,
  winter steelhead
• Other Interesting Wildlife Elk, black bear,
  cougar, bald eagle, osprey, blue heron
• Number of Dams Two -
• Howard Hanson Dam, Built 1962 and
• Tacoma Water Supply Diversion Dam, Built 1911

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Watershed words

• Headwaters Source of a stream.
• Watershed The land from which rain collects and
  runs to a single point.
• Groundwater Water that lies beneath the earth's
  surface.
• Infiltration The slow movement of water from the
  surface to the groundwater.
• Hydrologic Related to water in all its forms.
• Aquifer An underground water supply flowing
  through rock.

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Historic Outlook

• Mid-1800s
• We have examined the valley of the Duwamish River
  and find it a fine country. There is plenty of
  room for one thousand travelers.
• Come at once."
• Today it is one of the most altered hydrological
  ecosystems in
• the Puget Sound basin.

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Historic Facts about the Green/Duwamish

• 1st European settlement in King County near the
  mouth of the Duwamish River in 1853,
• the river carried four times as much water as it
  does today.
• To date,
• 97 percent of the river's estuary has been
  FILLED,
• 70 percent of the flows of its former watershed
  have been DIVERTED out of the basin and
• 90 percent of the once-extensive floodplain is
  NOT FLOODED on a regular basis.

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Fill

• Upper Green River Basin lies primarily in the
  boundaries of the Mt. Baker-Snoqualmie National
  Forest and has been extensively LOGGED

UW
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Fill

• Middle Green River basin has high AGRICULTURAL
  use -- much of the original forests and riparian
  zones have been cleared for pasture.

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Fill

• Lower Green/Duwamish Basin begins at Fort Dent
  Park near Tukwila. A major area of DEVELOPMENT

http//www.historylink.org, kiro
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Diversion

• 1907 the White River was permanently diverted
  into the Puyallup River
• The Black River was the outlet channel of Lake
  Washington and the Cedar River.
• 1916 Ship Canal and Locks built
• Lake Washington was lowered nine feet, and the
  Black River was cut off from the Duwamish.
• Cedar River was redirected to Lake Washington

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Black River

• 1916 Lk Washington was lowered 8.8 feet

The Black River ran out of the southern end of
Lake Washington. It flowed south through Renton,
and then veered west and merged with the Green
River to form the Duwamish River. The point where
the Black River merged with the Duwamish was in
Tukwila just north of present-day Southcenter
Mall, near the site of Fort Dent Park.
http//www.historylink.org/essays/output.cfm?file_
id2624
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Cedar River

• Until 1912, the Cedar River emptied into the
  Black River and became part of the Black River,
  which then emptied into the Duwamish.
• In 1911, the Cedar River flooded Renton. The
  following year the town dug a 2000-foot-long,
  80-foot-wide canal to reroute the course of the
  Cedar to the north so that it flowed directly
  into Lake Washington, in the hope of avoiding
  floods in the future.
• Masonry Dam

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Ship Canal and Locks

• link for boats between the saltwater of the Puget
  Sound and the fresh water of the Ship Canal
  connecting to Lake Union and Lake Washington.
• Timber and coal transport

http//www.ci.seattle.wa.us/tour/locks.htm,
historylink.org
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Development
http//dnr.metrokc.gov/topics/map/aerials/1970LkMe
ridian.htm

• from the 1930's, 1970's and 1990's illustrating
  growth around Lake Meridian in the Soos Creek
  drainage

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Lake Meridian
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Lake Meridian
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Lake Meridian