Quick Answer
The contour line strategy is a fundamental aspect of permaculture design, particularly for swales and berms, allowing for efficient water harvesting and soil retention.
Understanding Contour Lines
Contour lines are imaginary lines drawn on a map or terrain that connect points of equal elevation. In permaculture design, contour lines are used to identify areas where water tends to stagnate or run off. By following these contours, permaculture designers can create effective water harvesting systems that mimic nature. For example, a contour line with a gentle slope of 1-2% can be used to direct rainwater to a swale or rain garden.
Designing with Contour Lines
When designing a permaculture site, contour lines can inform the placement of earthworks such as swales, berms, and rain gardens. By placing these features along contour lines, designers can create a self-sustaining hydrological cycle that reduces soil erosion and increases water retention. For instance, a 20-meter-long swale following a 1% contour line can capture up to 10 cubic meters of water per hour during a moderate storm event. By incorporating contour lines into the design process, permaculture designers can create resilient and efficient water harvesting systems.
Techniques for Working with Contour Lines
To create effective contour line designs, permaculture designers can use a variety of techniques. One approach is to use a " contour template" – a physical or digital model that represents the terrain and contour lines. This template can be used to visualize and plan contour line designs, ensuring that earthworks are placed in optimal locations. Another technique is to conduct a “water walk” – a physical survey of the terrain to identify areas where water flows and accumulates. By using these techniques, permaculture designers can develop contour line designs that are tailored to the unique characteristics of each site.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.