Here
are my observations on the data for Lake Sacheen:
· There were no Enterococci bacteria present in the sample.
· The algae cell counts were all on the low side.
· With regard to water chemistry – turbidity was low (anything
less than 25 NTU is considered good); total nitrogen was low (anything less than 1.0 ppm is good); total phosphorus was low
(anything less than 25 ppb is good); chlorophyll-a was low (anything below 2.0 ug/L shows low algal densities); and the Secchi
depth reading was good – over 18 feet.
I
can’t really tell you anything about the zooplankton data – I will have to learn about those results as I write
the final report.
To
answer your question about blue-green algae, yes they can be a problem when they produce toxins. Not all blue-green
algae species produce toxins and even the species that do, don’t always produce the toxins. It still hasn’t
been determined what conditions cause a blue-green algae to produce toxins.
Ecology
currently has a blue-green algae sampling program where they will pay for toxin analysis on water samples collected from a
lake. Here is a link to a website explaining the program……………
http://www.ecy.wa.gov/programs/wq/plants/algae/index.html
On
this day, your lake looked good. But it is very important to remember this is only a single snapshot in time.
The only way to determine the state of your lake is to collect results over a period of time.
Please
let me know if you have any additional questions.
Maggie Bell-McKinnon, biologist
Environmental Assessment Program
Washington State Department of Ecology
PO Box 47600
Olympia, WA 98504-7600
phone: (360) 407-6124
email: MBEL461@ecy.wa.gov