What is a watercourse that flows continuously at all times of the year called?

A watercourse that flows continuously throughout the year is referred to as a perennial stream. This type of stream typically has a consistent flow of water due to the presence of groundwater that supports it even during dry seasons. Perennial streams are vital components of the hydrological cycle, contributing to ecosystem health and providing habitats for various aquatic and terrestrial wildlife. They are also an essential water source for nearby communities.

In contrast, intermittent streams exhibit flow only during certain seasons or periods, typically during rainy weather or snowmelt, while ephemeral streams flow only during specific rain events and are dry at other times. A floodplain stream is more about the area surrounding a stream that can be flooded rather than the flow characteristics of the stream itself. Understanding these definitions helps in recognizing the importance of perennial streams in maintaining ecological balance and resource availability.