How does urbanization typically affect stream discharges within the community?

Urbanization typically leads to an increase in stream discharges within a community due to several factors associated with land development. As urban areas expand, natural landscapes are altered or replaced by impervious surfaces such as roads, parking lots, and buildings. This change significantly impacts how rainwater and snowmelt are absorbed and channeled.

In undeveloped areas, much of the precipitation infiltrates the ground, replenishing groundwater and gradually entering waterways over time. However, in urbanized environments, the increase in impermeable surfaces reduces the amount of water that can infiltrate the soil. Consequently, more water runs off quickly, leading to higher peak flows in streams and rivers during rain events.

Additionally, urban drainage systems, including storm sewers and drainage ditches, are designed to quickly remove excess water from streets and neighborhoods. This system exacerbates the issue by directing large volumes of runoff into water bodies, resulting in increased stream discharges. Such changes can elevate the risk of flooding and alter the natural hydrology of the area, leading to more frequent and intense flood events.

Overall, the alteration of the landscape through urbanization fundamentally increases the volume and speed of water flow in streams, making the increase in stream discharges the correct outcome.