In the North Texas Region there are various types of power plants that produce electricity. A major problem of electricity producing power plants is thermal pollution. Thermal pollution can be defined as a major change in the temperature of water . This results when power plants discharge heated water into a reservoir . It is usually an increase in the temperature which can affect the aquatic life, i.e. aquatic insects, fish , phytoplankton, zooplankton, and algae.One of the main factors affecting aquatic life is a decrease in dissolved oxygen. There are two ways in which thermal pollution brings about a decrease in dissolved oxygen. An increase in temperature decreases the solubility of gases. Furthermore, an increase in water temperature increases metabolic rates of aquatic organisms which increases the demand for oxygen. This increased metabolism in fish results in a greater need for nutrients; therefore, they feed more often, lowering the supply of aquatic insects. Initially the increased heat of the water steps up the rate of photosynthesis which increases plant growth. At night the larger supply of plants results in a greater need for oxygen for respiration. The reduced levels of oxygen eventually result in reduced levels of aerobic bacteria which are necessary for decomposition of dead plants and animals.
In addition to the biotic effects of thermal pollution, there are also abiotic effects. Increased water temperatures accelerate evaporation which leads to higher levels of dissolved ions. This would be evidenced by increased conductivity. The decaying plant and animal matter and increased dissolved ions can additionally result in decreased water clarity (visibility).