Geo-Ecology : Recent Projects

Classification and Distribution of Lake Types in Washington State

The biophysical characteristics of lakes, such as hydrology, watershed size, flushing rate, size, shape, depth and trophic state, are principally established when a lake forms. In turn, these characteristics influence a lake shoreline's ecological functions, as well as their sensitivity to ecological changes. Using a series of scoping questions outlined in a Decision Support System for Lake Shoreline Assessment developed for the Washington Department of Ecology, over 1100 lakes over 20 acres in size were classified into several principal types: coastal, crater, coulee, glacial flood scour, glacial drift plain, kettle, glacial scour, cirque, oxbow, and impoundment lakes. Accessed through GIS datasets, aerial photographs, topographic maps, and lake reports, primary variables used by the classification framework included physiographic zones, surficial geology, basin shape, hydrology, and degree of human modification. This classification provides for a better understanding the physical characteristics influencing shoreline functions and processes, as well as each lake type's relative sensitivity in terms of nonpoint pollution, changes to recharge, littoral zone impacts, and alteration of wave energy regimes. Statewide distributions of lake types are also presented and linked to patterns of lake ontogeny.

Download lake classification data in GIS format

Related Publications:

Gabriel, A., A. Perkins, and J. Rhoades. 2007. Classification and distribution of lake types in Washington State. Poster presented at the 2007 North American Lake Management Society Symposium, Coronado Springs Resort, Orlando, Florida, Oct. 30 – Nov. 2, 2007.

Gabriel, A., K. Lillquist, A. Perkins, J. Rhoades. 2006. Classification and distribution of lake types in Washington State. Presented at the Pacific Northwest Regional Conference, Portland State University, Portland, Oregon, Sept. 13-15, 2006.

Gabriel, A., K. Lillquist, A. Perkins, J. Rhoades. 2006. Classification and distribution of lake types in Washington State. Presented at the Northwest Scientific Association Annual Meeting, Boise, Idaho, March 6-8, 2006.