• Mercer Slough Basin Drainage Details

    Header Image
    Conservation Banner 6-14-17.jpg

    Lake Washington Watershed (WRIA 8) / State Stream #08-0259

    Updated: July 2017

    The City of Bellevue does not guarantee that the information on this map is accurate or complete. This data is provided on an "as is" basis and disclaims all warranties.

    BasinFactSheet_Mercer Slough.jpg

    Please check out the PDF fact sheet version

    Land Characteristics

    Basin Area
    1,332 Total Acres
    City Area
    6.2%
    Drainage Jurisdiction(s)
    Bellevue: 100.0%
    Beaux Arts: 0.0%
    Clyde Hill: 0.0%
    Issaquah: 0.0%
    King County: 0.0%
    Kirkland: 0.0%
    Medina: 0.0%
    Newcastle: 0.0%
    Redmond: 0.0%
    Renton: 0.0%
    Lowest Elevation
    16 Ft
    Highest Elevation
    467 Ft
    Total Length of Open Channel
    3.3 Miles
    Total Length of Storm Drainage Pipes:
    20.9 Miles

    Salmon Present in the Basin

    • Chinook*+
    • Coho+
    • Sockeye
    • Rainbow & Cutthroat Trout
    • Steelhead (Lake only)

    * Listed Federal Endangered Species
    + City Species of Local Importance (Bellevue Land Use Code 20.25H.150A)

    Population

    The population density in Bellevue ranges from 1,344 to 9,851 people per square mile.

    Basin Population (2016)
    4,900
    % of all Basins
    3.2%
    Basin Population Density
    2,354 People per Square Mile

    Land Use

    Entire Basin Within Bellevue
    Public Right of Way 25.9% 25.9%
    Commercial/Office 6.4% 6.4%
    Industrial 0.5% 0.5%
    Institutional/Government 3.6% 3.6%
    Mixed Use/Misc 3.5% 3.5%
    Multi-Family 1.4% 1.4%
    Open Space/Park 24.7% 24.7%
    Single Family Residential 28.6% 28.6%
    Unknown 5.4% 5.4%

    Land Cover

    Entire Basin Within Bellevue
    Impervious 33.5% 33.5%
    Tree Canopy 43.2% 43.2%
    Impervious in 100 Ft Stream Buffer 8.0% 8.0%
    Tree Canopy in 100 Ft Stream Buffer 52.8% 52.8%