Which of the following is a disadvantage of groundwater?

• A. Easy access
• B. Difficult to determine volume available
• C. Stable temperature
• D. Low turbidity

Answer: (B)

Groundwater is stored in underground aquifers, so you can’t directly see or measure the total amount available. Estimating how much water can be safely withdrawn depends on aquifer geometry and properties—porosity, thickness of the saturated zone, recharge rates, and how water is stored and released (storativity). These factors vary greatly by location and are inferred from indirect data like well levels, pumping tests, and hydrologic models, introducing substantial uncertainty. That uncertainty makes it difficult to determine the exact volume available for reliable use, which is the main disadvantage. By comparison, groundwater often has favorable attributes such as shielding from surface conditions and the possibility of stable temperatures and low turbidity, which are not disadvantages.