Surface Runoff

September 15, 2021

Surface Runoff -  \ ˈsər-fəs ˈrən-ˌȯf / noun

The flow of excess water (along with nutrients) across the surface of the land. 

Surface Runoff in the Forest Garden:

Surface runoff represents the loss of two things:

  1. Water that could be captured or encouraged to infiltrate the ground as a resource for future farm resilience.
  2. Precious topsoil and nutrients which are inevitably carried with water runoff through erosion.

To avoid losing these things, farmers will choose to apply a few different techniques in their garden to mitigate the flow of water, slow it down, and allow it to sink into the soil. On sloped land, the issue is far more prevalent, so farmers identify the contours of their field, dig trenches, and plant vegetative berms along them to prevent the water from flowing downslope. Another useful technique is planting half-moon berms for fruit trees where excess water will spill out of one berm and then be captured by the next berm downslope. Mulching, maintaining the soil under vegetation, and having a diverse layered Forest Garden all contribute to reducing surface runoff. 

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