The Bradshaw Model is a geographical model which describes how a river's characteristics vary between the upper course and lower course of a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

. It shows that discharge

Discharge

Discharge in the context to expel or to "let go" may refer to:* A military discharge, issued when a member of the armed forces is released from service* Termination of employment, the end of an employee's duration with an employer...

, occupied channel width, channel depth and average load quantity increases downstream

Downstream

-Science:* In geography, away from the source of a stream or river* In meteorology, away from the source of an air parcel or mass, along the normal direction of water or air flow* Downstream , in computer or telecommunications networks...

. Load particle size, channel bed roughness and gradient are all characteristics which decrease downstream

Downstream

-Science:* In geography, away from the source of a stream or river* In meteorology, away from the source of an air parcel or mass, along the normal direction of water or air flow* Downstream , in computer or telecommunications networks...

.

The Origins of the Bradshaw Model

The model first appears as an illustration in M J Bradshaw's 1978 high school textbook The Earth's Changing Surface. Bradshaw's illustration is a simplification of Stanley Schumm's river model which had been published a year earlier in The Fluvial System, although aspects of the model had already appeared in a series of academic papers over the previous 10 years. Schumm based his model on an empirical analysis of a variety of North American rivers and suggested that it could be used to predict how any given river channel would respond to changes in discharge or sediment supply caused by river engineering, such as a dam

Dam

A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

or flood relief channel.