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Land Application and Lagoon Systems

The waste treatment pond, or stabilization pond, is a special method of biological treatment deserving attention. Ponds do not resemble the concrete and steel structures or the mechanical devices, but simple depressions in the ground capable of producing an effluent comparable to some of the most modern plants.

The first wastewater collection systems in the ancient Orient and in ancient Europe discharged wastewater into nearby bodies of water. These systems accomplished their intended purpose until overloading, as in modern systems, made them objectionable.

In ancient times, ponds and lakes were purposefully fertilized with organic wastes to encourage the growth of algae which, in turn, greatly increased the production of fish due to the food supply provided by the algae. This practice still continues and is a recognized art in Germany.

The first ponds constructed in the United States were built for the purpose of keeping wastewaters from flowing into places where they would be objectionable. Once built, these ponds performed a treatment process that finally became recognized. Because ponds are deceptively simple (their words - I think lagoons only appear simple but are really complex! ), they are probably neglected more than any other type of wastewater treatment process. Many of the complaints that arise regarding ponds are the result of neglect or poor housekeeping. The almost spontaneous mixing of all layers of water in a reservoir or lake when the water temperature becomes similar from to top bottom is known as 'overturn', also referred to as the pond is turning over.

Algae are unicellular, generally nonmotile plants. All plants use photosynthesis as their primary mode of nutrition. Algae are typically not of health concern; however, certain species may produce endo- or exotoxins, which, if ingested at high enough concentrations, may be harmful.

My concepts of an ideal lagoon: Anaerobic: Lined, 20 feet deep, covered, rectangular 3:1 L : W, near vertical walls, Influent pipe positioned at bottom, directed up and at width from opposite side. Bottom, not flat, but sloped up to effluent end and to side opposite influent (encouraging gravity settling of solids to small collection depression near influent pipe). Insulation will be necessary. The bacteria function best at their temperature and the earth at 20 feet is a pretty good heat sink. Sized for a detention time of 30 days minimum. Built in sensors, built in composite sampling. Effluent Weir: piped subsurface opposite corner from influent. Surface Weir: collect floatables for further processing. Edges: Diked to exclude rain infiltration and safety while allowing access for inspection and maintenance. [Expensive? Yes, at first; several decades later the summed costs will be much lower than alternatives - higher technology - labor - maintenance .]

Effluent Weir: Many, not one, at several dispersed locations in the effort to reduce possibility of short circuiting. Then piped together. Since the water at some point in the system will be pumped, the anaerobic lagoon should be the lowest level in the system and pumped up to the next in series. Likewise, the surface weirs will function best in the four corners of the lagoon and pumped to additional treatment. It seems that an anaerobic lagoon is a waste of effort (this is where anabolism is prevalent not catabolism), the wastestream loading is converted but not to carbon dioxide and water, so more conversion is needed.

10 Million gallons of water can cause a lot of damage when let go all in an hour or less. That is one on the reasons the State of Georgia has some pretty strict laws concerning the structure of large bodies of water and their dams or berms or dikes. Erosion control is important. Any grasses, shrubs which aid erosion prevention of the dikes are to be encouraged. Some owners realize the importance so much that the tops of the berms are asphalted for