One way to avoid blowouts is to use half dams. These are dams, often permeable, that extend half-way across a ravine. The purpose is to cause the stream to meander rather than running in a straight channel. The faster water goes, the deeper and straighter it cuts, creating ravines that encourage it to run off the land and leave nothing to soak in.
Forcing it to meander slows it down, allows some silt to drop, and creates a beachhead. Half dams can be placed in a ravine to move it away from a house foundation, for instance, rather than undermining it.
A meander gone wrong. Where is the half dam when you need one? (This is not the house my teacher wrecked, btw, but similar idea.) Where would you place the half dam?
Half dams allow one to spread runoff across the landscape in a zigzag, replicating the natural form of a healthy stream or river. This can be combined with other techniques to spread the water into the landscape, such as a “V” cut. A “V” cut perpendicular to the stream would create a side channel where water could trickle into and sink in. Trees can be planted by this, increasing the stability of the stream banks and creating more organic material to feed the soil.
By understanding the nature of water and how water naturally hydrates a landscape when trees are protecting it and holding banks in place, we can design earthworks that replicate those functions and reverse the erosion and desertification process that happens after a clear cut. This is being done in desertified landscapes all over the world, by permaculturists and other water whisperers.