• Lake Marcel had fairly clear water with moderate nutrient concentrations and high algal growth.
• Long-term trends suggest that water quality in Lake Marcel has been improving over time, with decreasing nitrogen concentrations, and deeper Secchi depths (clearer water).
• Nitrogen-to-phosphorus (N:P) ratios were periodically below 25 for the monitoring season, indicating times when the algal community was more likely to be dominated by cyanobacteria (which have the ability to produce toxins).
• Samples were submitted for toxin testing from June through December. Toxin testing found elevated microcystin concentrations in September, exceeding the Washington State Recreational Guidelines.
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).
