An evaporation pond is a shallow body of water typically constructed with a large surface area for the sole purpose of allowing the water to dissipate through the effects of sunlight and heat. There are a number of common uses for evaporation ponds. Salt evaporation ponds, used to obtain salt for seawater, have been used for centuries in various parts of the world. Evaporation ponds are also traditionally used in rural areas to capture agricultural runoff. Historically, in many parts of the world, they were used for treatment of the vegetable wastewater from olive oil. These ponds are typically cost-effective in spite of the large land area required. Desalination plants use evaporation ponds to dispose of brine, and ponds are used in mining to separate various ores from water. Evaporation ponds are commonly used by wastewater treatment plants, and they are employed at contaminated sites to separate hazardous waste, which can then be processed and stored safely.
Additional uses for evaporation ponds in today’s world are routinely developed and employed for reasons of environmental protection and to prevent toxic pesticides, fertilizers, salts and organic waste from contaminating groundwater or nearby bodies of water. Ponds are still important adjuncts to agricultural operations, and they help to alleviate some problems caused by modern manufacturing as well as to evaporate precipitation that may fall on contaminated sites. The use of strategically-placed evaporation ponds helps to protect natural watersheds, but their use can also be problematic in some cases due to the odor produced by organic waste. Odor abatement is a critical part of evaporation pond design for modern wastewater treatment plants located near urban areas. Location is only one of the considerations that must be factored into the development and use of evaporation ponds. Climate is another critical factor, and the long-term effect on the environment, including wildlife, has become a contemporary concern in many locales. Evaporation ponds, generally, are highly effective in sunny, arid climates, and in areas with a minimal rainy season. Natural precipitation can fill a pond more quickly than natural evaporation can occur in some cases. In some areas, where the use of evaporation ponds is deemed a necessity to extract minerals other materials from water, including mining operations around the Dead Sea and the Great Salt Lake in Utah, evaporation ponds are operated on only a seasonal basis.
