How does urban development typically impact stormwater runoff?

• A. It decreases the volume of runoff
• B. It increases the volume and speed of runoff
• C. It has no significant impact on runoff
• D. It provides better filtration of stormwater

Answer: (B)

Urban development typically increases the volume and speed of stormwater runoff due to several factors commonly associated with urbanization. When landscapes are developed, natural surfaces such as forests, grasslands, and wetlands that absorb rainfall are replaced with impervious surfaces like roads, buildings, and parking lots. These impervious surfaces do not allow water to infiltrate into the ground, leading to increased runoff.

Additionally, urban areas often have altered drainage systems designed to channel water quickly away from developed areas, which further accelerates the flow of runoff into nearby water bodies. The combination of more water being directed into storm drainage systems and the faster movement of that water can lead to increased flooding risks, as well as water quality issues due to pollutants being swept into waterways more rapidly. This can significantly exacerbate issues like erosion, sedimentation, and pollution in local water bodies.

The other options do not accurately describe the relationship between urban development and stormwater runoff, as they either suggest a reduction of runoff, no impact, or improved filtration, which is contrary to the realities of urbanized landscapes.