• Echo Lake continues to have fairly clear water, with high nutrient concentrations and high algal growth.
• Numerous algal bloom samples were collected for toxin testing in 2023. In October, toxin testing found elevated microcystin concentrations: 10 µg/L, above the Washington State Recreational Guideline of 8 µg/L.
• Investigate potential sources of phosphorus that could be contributing to increasing phosphorus trend.
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).