Ken Lake Water Study

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Ken Lake Water Study

• 6/6/06
• Conducted by
• Chris Sogn, Avanti High School Science Teacher
• David H., Avanti High School Multi-Talented
  Student

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Purpose

• The purpose of our study is to
• See how our lake has changed in the past 17
  years.
• Measure the health of our lake to serve as a
  baseline.
• Educate Ken Lake residents on ways to keep the
  lake healthy.

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Implications

• The underlying reason we are so avidly testing
  and studying the lake is in response to proposed
  development of the watershed that drains into the
  lake.
• We dont want to see our beautiful forests
  destroyed and we want to inform people about how
  to preserve the quality of the water.

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Arial View of Ken Lake
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Regional topography
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Formation of Ken Lake

• Ken Lake formed thousands of years ago. It is
  not man made.
• It it is the product of a glacier which retreated
  into the lakes location during the Vashon
  Glacier recession.

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Geology of Ken Lake
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Depth Map of Ken Lake
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Factors That Influence Water Quality

• The Lakes pH (acidity).
• Water Temperature
• Amount of Dissolved Oxygen
• Bacteria
• Turbidity
• Amount of Nutrients

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Tests Performed

• Dissolved Oxygen- A test to see how much oxygen
  is in the water.
• Fecal Coliform- A test to measure the amount of
  bacteria in the water.
• pH- A test to determine the acidity of the water.
• Secchi Depth- Determines turbidity (water
  clarity) and depth of water.
• Nutrients- A test to find the amount of
  phosphates and nitrates in the water.

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Optimal Water Quality Standards

• Dissolved Oxygen- 9mg dissolved Oxygen per liter
  of water.
• Fecal Coliform- Less than 50 fecal colonies per
  100 ml of water.
• pH- Between a rating of 7 and 8.
• Secchi Depth- The clearer the water the better.

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Data table
Test Performed Optimal Result Test Result
Dissolved Oxygen 9mg/l 9.5mg/l
Fecal Coliform 50 colonies per 100ml Results ranged from 10 to 29 colonies at the East Beach and 0 to 59 at the West Beach.
pH Between 7 and 8 7
Secchi Depth Clear to the bottom. Though some variation should occur over the seasons. At two locations (9.5 ft and 12ft) the water was clear all the way to the lake bottom.
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Water Test results, 2008
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Where to Go From Here?

• More Tests?
• Suggestions?
• ?

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Resources
A special thanks to Anne Mills and South Sound
Green for providing materials and resources with
such expediency!
Thank you to the Washington State Department of
Ecology for guidance and resources in conducting
this study.