Which of the following is a disadvantage of surface water that is often seasonal?

• A. Seasonal flows sometimes unreliable
• B. Easy to access
• C. Stable temperature
• D. Consistent supply

Answer: (A)

Seasonal surface water varies with the seasons, so the amount and timing of flow can swing from flood to drought. That variability makes the supply unreliable because water may be plentiful at some times and scarce at others, complicating planning, storage, and treatment needs. The other options describe things that aren’t the drawback: easy access is not inherently a disadvantage, surface water isn’t typically characterized by a stable temperature, and a consistent supply is precisely what seasonal variability undermines.