What effect does urbanization have on water resources?

Urbanization typically leads to intensified development and population growth within cities, which can significantly impact local water resources. As urban areas expand, land that was previously absorbent—like forests, wetlands, and fields—often gets replaced with impervious surfaces such as asphalt and concrete. This change hinders the natural absorption of water into the ground, leading to increased runoff.

Moreover, greater urban densities usually mean more waste generation and pollutants being introduced into the water system, either through direct discharge or runoff during rainfall events. This can significantly increase the levels of pollutants in local rivers, lakes, and groundwater, contributing to lower water quality and potentially harming ecosystems and human health.

Additionally, urbanization can place additional demands on existing water supply systems as more people require access to clean water for drinking, sanitation, and irrigation. This strain on water resources can lead to over-extraction from rivers and aquifers, further exacerbating pollution and scarcity issues.

In summary, urbanization poses challenges to water resources primarily by increasing pollution and overwhelming local systems, making the second choice the most accurate in describing its effect.