What is the effect of a cold snap on water systems?

The correct choice highlights a significant impact of a cold snap on water systems. When temperatures drop substantially, water inside pipes can freeze. This freezing can lead to an increase in pressure within the pipes since ice expands and occupies more space than liquid water. If the pressure exceeds the pipe's ability to contain it, it can result in pipe bursts. These breaks not only disrupt the water supply but can also lead to property damage and costly repairs.

Understanding this phenomenon is crucial for managing water systems, especially in regions prone to harsh winter conditions. Strategies to mitigate such risks include insulating pipes, maintaining a consistent flow of water, and monitoring temperatures closely during expected cold snaps. Other options mentioned do not accurately represent the main effects associated with cold temperatures on water systems. For instance, while there might be temporary changes in water pressure and quality, the primary concern remains the structural integrity of the pipes under extreme cold.