Thursday, October 2, 2014

Algae in the lakes and ponds

Algae are a source of food and energy for fish and other lake organisms and a vital part of all lakes. However, sometimes we get too much algae in our lakes and the resulting algae mats occur.  So how does this happen?
Algae in the lake bottom
Algae in the ponds and lakes have been more widespread than in previous years due to less oxygen transfer and less large rainfall events.  Rain tends to be a good dilution factor for temperature variations and is also an oxygenator for the ponds and lakes.  Most algae do not form in moving water.  So when we have heavy rain events, the algae does not form because the water from all the creeks increases the water velocity in the lakes (remember all of our lakes are dammed creeks and rivers).  Additionally, the fast moving water mixes and oxygenates the water which also discourages algae.
Algae in #17 lake
While the amount of algae in our lakes is considered to be minor, it is nonetheless unsightly.  We have tried to remove the algae by hand but that has turned out to be an exercise in futility as the algae just grows back in a few days.  We have also tried to use chemicals to kill the algae.  While that has worked to some extent, we are limited in how much can be applied since the water is used for irrigation and the chemicals can also kill grass.  Our best option is to let Mother Nature do her thing.  As fall has arrived, the cooler temperatures will take care of the algae on its own and naturally.