18
THE KANSAS LIFELINE
July 2018
By Doug Helmke, P.G., Water Rights/Source Water Specialist
n recent years, it has been common for the Kansas
Department of Health and Environment to issue
Public Health Watches and Warnings due to the
occurrences of Harmful Algal Blooms (HABs). Since
2011, an annual average of 16 Kansas counties have had
a publically-accessible pond, lake or reservoir with a
bloom. These toxic blooms have the potential to impact
drinking water, so what is being done to prevent them?
Cyanobacteria are prokaryotic cells that produce oxygen
through photosynthesis. Animals and plants have eukaryotic
cells, cells with specialized parts surrounded by a membrane
which perform specific functions. Cyanobacteria, while capable
of photosynthesis, are more like bacteria than plants. Algae is
also not very plant-like, but do have the specialized cell parts and
do perform photosynthesis. The function of photosynthesis was
once thought to belong exclusively to plants, hence the early
classification of cyanobacteria as “blue-green algae” and the
continuation of labeling these blooms as “algal.” For more
information on the biology
of algae and the water treatment options for cyanotoxins,
see the November 2016 Kansas Lifelinearticle
“Cyanotoxins Produced by Blue-Green Algae”
(
https://www.krwa.net/portals/krwa/lifeline/1611/056.pdf
).
Cyanobacteria is found nearly everywhere. When an
abundance of nutrients is present in bodies of water, the rapid
population explosion of bacteria (and other algae too) can occur.
When conditions are right for cyanobacteria, they can visibly
change the appearance of the water. A scum can accumulate on
the surface, and the water can have a color not unlike traditional
antifreeze (green ethylene glycol). Cyanobacteria does not seem
to negatively affect fish or other aquatic life. However, the
bacteria and the toxins it releases can cause illness in humans
and their pets. Fortunately in Kansas, enough dilution during
and after reservoir releases has kept the amount of toxin below
regulatory levels at downstream water treatment facilities.
The problem with these cyanobacteria blooms, at the
present time, are the public health risks with direct contact,
and the negative perception of the water quality when
watches are declared. For the major reservoirs that provide
recreational opportunities, it’s likely that some of the people
that fish and enjoy watersports may travel to reservoirs where
watches aren’t declared. When a warning is declared, more
I
State Tries Ultrasound to
Control Cyanobacteria
When in Doubt, Stay Out!
Raw water from the Marais des Cygnes River is pumped into this
settling pond where the stilling and sunlit environment is
conducive to algae reproduction. While sediment settles,
ultrasound emitters operate to keep algae at minimal levels.
District management believes that these devices are helpful in the
District’s effort to produce high quality drinking water.
Owners of lakes and ponds will pos
t HAB Watch signs when
KDHE determines tha
t an algal bloom
may be imminen
t.