How does urbanization typically affect waterways?

Urbanization typically affects waterways by increasing runoff and pollution. As land is developed for urban uses such as housing, roads, and commercial buildings, the natural landscape is altered, and impervious surfaces like concrete and asphalt are created. These surfaces prevent water from infiltrating into the ground, leading to increased runoff during rainfall events.

This runoff can carry various pollutants, such as oils, heavy metals, and nutrients from fertilizers, directly into waterways without the natural filtering that occurs in undisturbed environments. As a result, urbanized areas often experience elevated levels of pollution in nearby rivers, lakes, and streams, which can harm aquatic life and degrade water quality.

In contrast, the other options suggest positive impacts of urbanization on waterways, which generally is not the case. Things like increasing natural habitats, reducing water temperatures, or improving ecosystem diversity are not typical outcomes of urbanization. Instead, the transformation of landscapes into urban settings tends to disrupt existing ecosystems and can lead to a decline in biodiversity.