What does stream competency refer to?

• A. The speed of the water flow
• B. The largest size of sediment particle a stream can transport
• C. The depth of the stream
• D. The width of the stream

Answer: (B)

Stream competency refers to the largest size of sediment particle that a stream can transport. This concept is integral in understanding how rivers and streams shape their environments. It is influenced by factors such as the stream's velocity, gradient, and overall energy level. When water flows at a certain speed, it has the capability to lift and carry sediment of varying sizes. As the velocity increases, a stream can transport larger particles. Understanding stream competency is essential for predicting sediment transport, erosion, and the overall dynamics of river ecosystems.

The other concepts mentioned, like the speed of the water flow, may relate to stream competency in that faster water can transport larger particles, but they do not define what stream competency actually measures. Similarly, the depth and width of the stream do not directly address the size of the particles that a stream can carry, which is the core meaning of stream competency.