Which of the following best represents a typical runoff coefficient for a parking lot?

Which of the following best represents a typical runoff coefficient for a parking lot?

• A. A. 0.15
• B. B. 0.35
• C. C. 0.65
• D. D. 0.95

Answer: (D)

A typical runoff coefficient for a parking lot is best represented by a higher value, as parking lots are generally made of impermeable surfaces like asphalt or concrete, which do not allow water to infiltrate easily into the ground. The choice that reflects this characteristic is the one with the runoff coefficient of 0.95. This high value signifies that 95% of the precipitation that falls on the surface will run off rather than infiltrating into the soil. The reason for this high coefficient is primarily due to the impermeable nature of the materials used. In contrast, lower coefficients would be more appropriate for surfaces that allow more water to absorb, such as grass or soil, which do not accurately represent the hydrologic behavior of a typical parking lot. Understanding runoff coefficients is essential for effective stormwater management and planning, especially in urban environments where impervious surfaces are common.

A typical runoff coefficient for a parking lot is best represented by a higher value, as parking lots are generally made of impermeable surfaces like asphalt or concrete, which do not allow water to infiltrate easily into the ground. The choice that reflects this characteristic is the one with the runoff coefficient of 0.95.

This high value signifies that 95% of the precipitation that falls on the surface will run off rather than infiltrating into the soil. The reason for this high coefficient is primarily due to the impermeable nature of the materials used. In contrast, lower coefficients would be more appropriate for surfaces that allow more water to absorb, such as grass or soil, which do not accurately represent the hydrologic behavior of a typical parking lot. Understanding runoff coefficients is essential for effective stormwater management and planning, especially in urban environments where impervious surfaces are common.