This page was last updated by the Content Provider on 01-Aug-2007
Stillaguamish River Basin
The Stillaguamish Basin is in the northeastern portion of the Puget Sound area about 50 miles north of Seattle. The basin extends from tidewater to the western spur ranges of the Cascade Mountains, encompassing some 684 square miles of drainage area. Major tributaries of the Stillaguamish are its North and South Forks and Pilchuck Creek. The topography ranges from low rolling terrain in the west to steep, mountainous areas in the southeast. Approximately 86 percent of the land is covered by forests. Agricultural lands along the coastal shelf and alluvial lowlands of river valleys make up most of the remaining area.
The climate is typical of the Puget Sound area with cool summers and mild winters. Precipitation ranges from 30 to 40 inches along the coastal plain to more than 100 inches in mountain areas. Precipitation falls mostly between October and June, with heavy snowpacks in areas over 3,000 feet.
Stillaguamish River
Completed Flood Control Project (Seattle District)
The Stillaguamish River is formed at the confluence of the North and South Forks at Arlington and flows westerly 22 miles to Puget Sound. A project completed in 1939 included snagging, bank revetments at 26 locations along the river and Cook Slough, channel changes between Arlington and the head of Hat Slough, cutoff channels, and a control weir at the head of Cook Slough. Federal costs through September 1998 were $501,594 for new work and $3,480,665 for maintenance.
Flood damages prevented through fiscal year 1998 totaled $4,830,000. An additional $21,000 in contributed funds was used for new work.
In 1995 a restoration study was initiated for ecosystem restoration throughout the Stillaguamish Basin with Snohomish County as sponsor. The study evaluated 18 restoration sites throughout the basin. The study is scheduled to go into feasibility in early fiscal year 1998 and be completed in 2000.
Stillaguamish Ecosystem Restoration Project
General Investigation Study, Deferred (Seattle District) A favorable report was completed in 2000 recommending the construction of 12 restoration sites in the StillaguamishBasin. SnohomishCounty withdrew sponsorship in 2005 during the Planning, Engineering, and Design phase.
Stillaguamish River, Stanwood
Section 205, Flood Control Study. Terminated (Seattle District) Feasibility study indicated a feasible project to protect Stanwood from SkagitRiver flooding. No feasible project was found to prevent flooding form the StillaguamishRiver. Study terminated in 2003 at request of the local sponsor, SnohomishCounty.
North Fork Stillaguamish River
Bank Protection Project, Terminated (Seattle District) In 1994, at the request of SnohomishCounty, Seattle District investigated the need for a bank protection project to protect a county roadway. The study was conducted under the authority of Section 14 of the 1946 Flood Control Act. The study was terminated at the request of local sponsor.
