King County Lake Inventory

Author

Curtis DeGasperi

King County Lake Inventory

For a preliminary assessment of the number of lakes in King County I used two data sources of lake coverage:

King County’s wtrbdy_con.shp file (“\\gisdw\KCLIB\Plibrary2\hydro\shapes\polygon\wtrbdy_con.shp”)
National Hydrography high resolution waterbody data: Access National Hydrography Products | U.S. Geological Survey (usgs.gov)

These lake data sources were intersected with kingco.shp and the intersection of kingco.shp and Ecoregion Level III Puget Lowland to estimate the total number of lakes in King County and the number of lakes withing the Puget Lowland of King County.

NHD High Resolution data

I used the Washington NHD shapefile coverage found here: The National Map (prd-tnm.s3.amazonaws.com). I downloaded the Washington zipped file and extracted the data.

EcoRegion Level III data

I also extracted the EPA Region 10 EcoRegion Level III shapefile and put a copy of the data in “./data/base/gis”.

King County and King County|Puget Lowland coverages

Now we can load the two coverages that we’ll use to intersect with the available lake data.

Number of Lakes using wtrbdy_con

[1] "Number of lakes = 228"

[1] "Number of lakes = 118"

Number of lakes >=1 acre using NHDWaterbody

[1] "Number of lakes = 883"

[1] "Number of lakes = 526"

Number of lakes >=4 acres using NHDWaterbody

[1] "Number of lakes = 381"

[1] "Number of lakes = 191"

Lake Area Histogram

It seems like we should also know something about the distribution of lakes of various sizes throughout the county….at least throughout the Puget Lowland.

[1] "Mean lake area for Puget Lowland lakes = 30 acres"

[1] "Median lake area for Puget Lowland lakes = 2 acres"

Number of lakes >=1 acre using LAGOS-US

[1] "Number of lakes in King County = 467"

[1] "Number of lakes in Puget Lowland of King County = 241"

…and the LAGOS-US lake area histogram…

[1] "Median lake area for King County lakes = 88 acres"

[1] "Median lake area for King County lakes = 8 acres"

[1] "Median lake area for King County Puget Lowland lakes = 134 acres"

[1] "Median lake area for King County Puget Lowland lakes = 7 acres"