Transcript Ken Lake Water Study

Ken Lake Water Study
6/6/06
Conducted by
Chris Sogn, Avanti High School Science Teacher
David H., Avanti High School Multi-Talented Student
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.
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 don’t want to see our beautiful forests
destroyed and we want to inform people
about how to preserve the quality of the
water.
Arial View of Ken Lake
Regional topography
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 lake’s location during the
Vashon Glacier recession.
Geology of Ken Lake
Depth Map of Ken Lake
Factors That Influence Water
Quality
 The
Lake’s pH (acidity).
 Water Temperature
 Amount of Dissolved Oxygen
 Bacteria
 Turbidity
 Amount of Nutrients
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.
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.
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.
Where to Go From Here?
More Tests?
Suggestions?
…?
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.