| Several factors may significantly affect or aid, the | | | | degree C and mild wind conditions. At a temperature |
| hydraulic and biological behavior of wastewater | | | | above 35 degree C, the rate of photosynthesis |
| stabilization ponds. Some, not all, can be taken care | | | | declines rapidly and at temperatures above 45 |
| of during designing a waste stabilization pond. | | | | degree C, it altogether stops. High temperatures |
| Natural factors | | | | stimulate growth of blue green algae at the expense |
| 1) Temperature | | | | of more efficient green algae. At the same time, |
| Temperature directly influences the physical, chemical | | | | aerobic bacteria in wastewater consume oxygen at |
| and biological activities in a waste stabilization pond | | | | higher rate creating conditions to form anaerobic |
| system. Rate of photosynthesis and cellular | | | | patches in the waste stabilization pond. Sudden |
| metabolism are directly proportional to the pond | | | | reduction in temperature slows down algae activity |
| temperature. Ponds should be designed for most | | | | and oxygen production. Algae will move to lower |
| adverse temperature conditions. At lower | | | | layers, the green color will reduce and pond |
| temperature, dissolved oxygen present has a | | | | performance will drop. |
| tendency to remain in pond longer. As the | | | | 2) Rainfall |
| temperature rises, dissolved oxygen is likely to be | | | | Rainfall influences pond performance. Detention time |
| liberated to atmosphere, especially under | | | | reduces when it rains. Besides, heavy shower dilutes |
| supersaturated conditions. The oxygen production by | | | | the contents of shallow ponds reducing the food |
| Algae in wastewater through photosynthesis is also | | | | available to biomass. Rainfall adds oxygen to a pond |
| temperature dependent. All ponds perform well on a | | | | system by increasing turbulence. |
| sunny, cloudless day at an air temperature above 20 | | | | |