The gradient of the stream's channel is referred to as stream gradient. It is the stream's vertical drop over a horizontal distance. We can use the following equation to compute it: [latex]Gradient=\\frac{change in elevation}{distance}[/latex] We commonly represent it in feet per mile or meters per kilometer. Stream gradients are often stronger in the headwaters (where the stream starts) and lower at the mouth (where it empties into some other body of water) (such as the ocean).