A baseline water quality study was completed in 2004, and alum treatments have been carried out to reduce phosphorus in 2005 and again in 2011 by the King County Lake Stewardship Program. Both treatments were successful, with summer monitoring following the condition of the lake to measure effectiveness. Further treatments may be necessary in the future, although improvements in the stormwater facilities and best management practices are ongoing in the watershed.
This bathymetric map shows contour lines of equal depth, similar to a topographic map would for mountains and valleys. The red 'X' marks the location where water quality samples are taken.
This map shows the area of the watershed relative to the area of the lake. Generally speaking, the larger a watershed is relative to a lake, the greater the influence land use practices on lake water quality.
The average of these three TSI indicators during the growing season can be used
to place lakes in one of three broad categories:
<40 = oligotrophic (low productivity),
40 to 50 = mesotrophic (moderate productivity)
>50 = eutrophic (highly productive).