The critical component of any lake or pond is the dam. In essence, without the dam, there is no pond. Man has been building dams for over 4,000 years. The first dams were constructed to prevent erosion, control flooding, and provide power and irrigation. After all these years the reason for dams has not changed.
Throughout Metro Atlanta, lakes and ponds dot the landscape. All are man-made impoundments and all have dams. Dams can be made of concrete slabs, but the most common type of dam is made of earth. Dirt is built up across the stream or drainage channel to back up the water and create a pond. Dams are built to hold a predetermined amount of water. An outlet control structure is installed through the dam to maintain the specific water depth and volume.
Unfortunately, routine and necessary maintenance of the dam structure is one of the most neglected and forgotten items on these water bodies. Whether the dam was built to continuously retain water or merely detain stormwater temporarily after a heavy rain event, the #1 rule of pond ownership is if water comes in, water must go out. If nothing else gets maintained with regards to your dam, you must be ever vigilant to ensure the outlet system is kept clear and free-flowing. Don’t forget the emergency spillway!!! It’s there for one reason only, to protect your dam when extreme rainfall overwhelms your primary outlet structure. It must be as clear and free-flowing as possible, but often is left overgrown and becomes a dumping ground for the landscapers.
As the Atlanta floods of 2009 exhibited, a clogged spillway can lead to catastrophe in the blink of an eye. State stormwater regulations recommend inspecting your outlets/spillways after every rain event. While this may be a bit ambitious for most lake and pond owners, we wanted to show a few quick examples of the costly damage ignoring the #1 rule can lead to.
