GEOSMIN
Smelly water does not mean unhealthy water if the odour
is caused by geosmin.
Rand Water’s consumers may experience odours in the water during the summer
months due to the presence of geosmin.
Geosmin is a naturally occurring odour producing substance found in surface
waters as a by-product of blue green algae.
The intensity of these odours is directly related to the increased densities of
blue-green algae normally occurring in the surface waters of the Vaal Dam during
summer.
The present problem is aggravated by the current sunny weather and high
temperatures causing ideal growing conditions for algae and this together with
the varying level of the dam results in the draw-off of surface waters containing
high quantities of blue green algae.
The odours are earthy or musty in character and are sometimes described as
smelling like green mealies.
These odours can be very persistent and are not effectively removed by
conventional water purification processes.
In view of the infrequent and usually short duration of the problem and the fact
that this compound is not harmful to human health, it is Rand Water’s view that
the high cost of removing this substance is not warranted at this stage.
Rand Water, however, remains committed to supplying safe and aesthetically
acceptable water and should our extensive water quality-monitoring programme
indicate an increase in frequency and duration of these occurrences, the
necessary steps will be taken to remedy the problem in due course.
Remember, geosmin does not present a health risk.
Visit www.reservior.co.za for further information on water quality in your area.