Remember that standard seven Geography class when you asked the teacher why learning how to read contours on a map will help you when you are all grown up? Well, today we answer that question. A topographic map of a dam shows all the features of the submerged area, e.g. submerged “koppies”, deep holes, drop-offs, ledges, flats and points. These are all shown by the contour lines, namely a series of concentric lines running all around the dam. These denote the topography of the entire submerged area. Each line represents the depth of the water at that particular point.
How can awareness of a dam’s contours help you when fishing from the bank? Probably the most obvious is the fact that you will be able to determine where the deeper waters are. Deeper water is not only colder, but the water temperature doesn’t fluctuate as much as the shallow water and it is generally also where the larger carp lies.
The darker the blue on the map below, the deeper the water:
Most dams have a riverbed running through it, and in some cases the riverbed lies close to the bank you will be fishing, and in other cases it will run close to the opposite bank. If you are able to determine how far you need to drop your bait in order to place it in the deep riverbed, you will certainly swing the odds in your favour. The Vaal Dam is a good example where one can clearly see where the original river flowed.
One of the best topographic features you can find is a deep hole. Food will congregate and settle in these holes and this is where the fish love to feed. Below is an example of what the hole will look like on the map:
One more thing to look out for is a “drop-off “close to the river’s path. You will be able to identify this by looking for areas where the contour lines run very close to one another. This means that the water gets deeper at a very steep rate in these areas. Also a good choice when deciding where to place your bait.
This area in Spioenkop Dam is a good example of “drop-offs” close to both banks:
The website below is a great tool to use if you want to do some research on the dam’s contours before a fishing trip.
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