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by
Michael B. Bolger, Ph.D.
Daily Graph of Russian River Low Flow Toxicity
Click here for a Periodic Blog on Observed Cyanotoxin levels and Factors that influence Russian River Toxicity
IMPORTANT DISCLAIMER:
The prediction of anatoxin concentrations and the risk of toxicity to humans and animals presented on this web page should not be used to
make decisions about personal safety or the use of Russian River recreation opportunities. These predictions are based on a simple mathematical
relationship between river water temperature, river flow, and air temperature that will never be absolutely accurate. My intention for the
publication of this model is to help the Sonoma County Water Agency and the Sonoma County Board of Supervisors to exercise adaptive management
of Russian River flow and thus avoid the bloom of blue-green algae and potential river toxicity.
Sonoma County residents: Feel free to check this web site as often as you'd like to see the predicted Anatoxin-a concentration in Russian River.
This simulation model does not provide specific geographical locations along the river for these predictions. The model uses daily river flow data
from the gauge at Hacienda, water temperature at 3:00 PM in Guerneville. and air temperature also from Guerneville. If you'd like more
detailed information about the equations used and background of the model development you can download the following report.
Report on Water Quality, Draft EIR, and Simulation Model
Click here for a plot of the predicted change in daily anatoxin concentration
Please don't let the Sonoma County Board of Supervisors (SCBOD) ignore this easily avoidable and potentially life-threatening
Russian River blue-green algae related toxicity! Encourage your supervisor and the Sonoma County Water Agency (SCWA) to adopt adaptive management of
Russian River flows. Let's use an advanced computer model to predict when to expect a bloom of blue-green algae and the subsequent increase in cyanotoxin
levels, and then adjust the river flow to easily avoid the potential toxicity.
Click here to see the historical predictions from 2015 to present.
NOTE: I have confirmed with the Sonoma County Department of Health that they did not conduct sampling in the month of July 2018. Consequently, the observed levels are zero
even though the predicted levels are significant.
NOTE: The water temperature (black line) has been divided by 10 so it can be plotted with anatoxin-a on the Left Y-axis.
NOTE: The July 30th, August 6th, and August 13th observed levels were for microcystin at Camp Rose and Steelhead beaches.The observed level of anatoxin-a on 8/20/2018 was 0.13 ug/L at Johnson's Beach
in Guerneville. Except for the anatoxin-a in Guerneville, these levels are well below even the "caution" level for the State of California.
My recommendation is for Sonoma County Residents to contact your supervisor and encourage them to instruct SCWA to utilize this type of
simulation model to manage the Russian River flows when the conditions of flow, water temperature, and air temperature could give rise to this
type of toxicity.
Here is a link to the Sonoma County Dept. of Health Services web page for current data on Blue-Green Algae and cyanobacteria:
SCDHS Blue-Green Algae
Thanks,
Mike
If you have questions, you can E-mail me at:
labsoft@comcast.net
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