Florida Drinking Water Operator "B" Practice Test

Metallic corrosion in potable water is always the result of what?

1. Physical erosion

2. Electrochemical reaction

3. Microbial action

4. Temperature fluctuations

The correct answer is: Electrochemical reaction

Metallic corrosion in potable water primarily occurs due to electrochemical reactions. In a water distribution system, metals such as iron or copper can react with water and dissolved oxygen, leading to the formation of corrosion products. This process involves the transfer of electrons between metal ions and the surrounding environment, typically resulting in the deterioration of the metal material. The presence of electrolytes in the water, combined with factors like pH and the presence of other chemicals, can further facilitate this electrochemical process. As the metal is oxidized, it can lead to issues such as rust in iron or copper leaching into the water supply, which can affect both the quality of the drinking water and the integrity of the pipes. Other factors listed, such as physical erosion, microbial action, or temperature fluctuations, may contribute to the overall integrity of the pipes and water quality but are not the primary cause of metallic corrosion itself. Physical erosion usually refers to mechanical wear and tear, while microbial action can influence biofilm formation but is not directly responsible for metal corrosion. Temperature fluctuations may impact corrosion rates but are also not the underlying cause of the corrosion process.