What type of stream is characterized by a continuously flowing watercourse?

A perennial stream is defined by its characteristic of having continuous flow throughout the year, regardless of seasonal variations in precipitation and temperature. This type of stream is consistently supplied with water from various sources such as groundwater, melting snow, or rain, which ensures that it maintains a flow even during dry periods.

In contrast, an intermittent stream only flows during specific times of the year or during particular weather conditions, such as after rainfall. Seasonal streams typically experience flow limited to certain seasons, usually tied to specific climatic patterns. Ephemeral streams, on the other hand, are those that only flow briefly during and immediately after precipitation events, often drying up quickly afterward.

Therefore, the defining feature of a perennial stream is its ability to provide a continuous water flow all year round, making it essential for maintaining ecosystems and habitats that rely on stable water availability. This characteristic is what distinguishes it from the other types of streams mentioned.