Most bushcraft shelters work well except when it rains. When inclement weather strikes, it can be a very wet shelter. Worse yet, it can start to flood on the dry floor that you need to sleep on. The solution to this is making a trench around your shelter.
The trench should at least be 3-6 inches (8-15cm) wide and deep, and it should encircle your shelter. Note where the water will run towards your shelter. Also, it needs to drain downward away from the shelter. As you trench around the shelter, make sure to take the dirt you dug up and pile it closer to the shelter. Also, find the point where it can drain downwards. Even though it may appear very flat in the area where your shelter is, there are still some locations that will be slightly downhill, and that is where you will build a trench away from the shelter. A good way to tell if it is downward in a specific direction is to get a large leaf (banana leaf or other long leaf) and pour a drop of water. If the water falls in one direction, change the angle of the leaf, and try again. Note the direction the water drops move, and that is the direction of the downhill. As you dig your downward trench, make sure that the depth gets shallower as it gets lower towards a creek or river.
One word of caution is now that you have trenches, you may fall into it and sprain your ankle. Make sure you cover the trenches with bark strong enough to support your weight in areas you need to cross over (like a small bridge) near the opening of your shelter. The water will flow underneath and still shed it away from the shelter.
