USGS groundwater studies South and East King County, Washington
The US Geological Survey produced two studies specifically for King County Groundwater Management Plans:
- D.G. Woodward, F.A.Packard, N.P.Dion, and S.S. Sumioka. Occurrence and Quality of Ground Water in Southwestern King County, Washington. Water-Resources Investigations Report 92-4098. Prepared in cooperation with: State of Washington Dept. of Ecology, Regional Water Association of South King Co., and Seattle - King County Dept. of Public Health. Tacoma. 1995.
- G.L. Turney, S.C. Kahle, and N.P.Dion. Geohydrology and Ground-Water Quality of East King County, Washington. Water-Resources Investigations Report 94-4082. Prepared in cooperation with Seattle - King County Dept. of Public Health. Tacoma. 1995.
The areas covered by these studies correspond closely to the South King County (214K Acrobat) and East King County (877K Acrobat) Groundwater Management Areas. The map plates below show the extent of the aquifers in these areas, and the contours for the water table at the time, or potentiometric surface, in those area aquifers.
|Geohydrologic Unit Label||Geohydrologic Unit Name
(layer of soil underground)
|Predominant Hydrologic Significance
(does it hold water?*)
|Potent. Surface Map (South**)||Potent. Surface Map (East)|
|Qal||Alluvium||Aquifer (some confining beds)||Plate 3(a)
|Plate 3(b) (.pdf, 253K)|
|Qvr||Vashon Recessional Outwash||Aquifer||Plate 3(b) (.pdf, 253K)|
|Qvt||Vashon Till||Confining Bed|
|Qva||Vashon Advance Outwash||Aquifer||Plate 3(a)
|Plate 3(c) (.pdf, 261)|
|Q(A)f||Upper fine-grained unit||Confining Bed|
|Q(A)c||Upper coarse-grained unit||Aquifer||Plate 3(b)
|Plate 3(d) (.pdf, 247K)|
|Q(B)f||Lower fine-grained unit||Confining Bed|
|Q(B)c||Lower coarse-grained unit||Aquifer|
|Q(C) or Q(C)u||Deepest unconsolidated and undifferentiated deposits||Variable|
|Br||Bedrock (East King Co. only)||Aquifer (but unreliable)|
* An aquifer yields water, while a confining bed does not.
This page is produced by the King County Groundwater Protection Program. To learn more about this group and its responsibilities, please read about the Groundwater Protection Program.