Erosion Challenge
Master natural engineering solutions to combat soil erosion, improve water retention, and transform barren slopes into productive, fertile landscapes. Learn how swales, terracing, and vegetation work together to slow, spread, and sink water.
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Interactive Erosion Simulation
Explore how different slope treatments affect water flow and erosion. Click on each slope to simulate rainfall and observe the differences.
How to use:
Click on any of the three slopes to see how water flows differently. Compare the bare slope, the slope with swales and vegetation, and the terraced slope.
Key Concepts
Let's Build It!
Now it's time to choose what you'll build to protect your hillside. Select the techniques that best fit your site and available materials.
Swale & Berm
A contour ditch with a raised planting mound. Best for gentle to moderate slopes.
- Difficulty: Medium
- Time: 2-4 hours per 10m
- Best for: Slopes 5-15%
Zuni Bowls
Rock crescents in drainage channels. Perfect for repairing gullies.
- Difficulty: Easy
- Time: 30 min each
- Best for: Gullies & channels
Micropond
Small water-holding basin. Creates habitat and stores water for dry times.
- Difficulty: Medium-Hard
- Time: 3-6 hours each
- Best for: Flat spots on slopes
Stone Terrace
Level step cut into the hillside with a stone retaining wall.
- Difficulty: Hard
- Time: Full day per terrace
- Best for: Steep slopes, rocky sites
Check Dam
Small barrier across a drainage path using logs, rocks, or branches.
- Difficulty: Easy
- Time: 1-2 hours each
- Best for: Stream beds & runoff paths
Ground Cover Planting
Fast-spreading plants that protect bare soil and hold it with roots.
- Difficulty: Easy
- Time: 1-2 hours to plant
- Best for: Any bare soil
Tools You'll Need
Based on your selections, here are the tools to gather:
Build Your Own A-Frame Level!
You'll need: 2 straight sticks (2m each), string, a weight (rock or bottle), and something to tie them together.
- Tie the two sticks together at one end to form an "A" shape
- Add a crossbar about 2/3 down for stability
- Hang a string with weight from the top joint
- On flat ground, mark where the string crosses the crossbar
- When the string hits that mark on a slope, both legs are at equal height!
Your Build Plan
Planting on Your Improved Hillside
Now that you've slowed and captured water, it's time to plant! Your improved hillside will support much more diverse and productive plants.
Wet Zone (Swale Bottom / Pond Edge)
These areas stay moist longest. Perfect for water-loving plants!
Suggested Plants:
- Willows - Fast-growing, great for cuttings
- Comfrey - Deep roots, nutrient accumulator
- Mint family - Spreads to cover ground
- Taro / Elephant Ear - Edible in tropical climates
- Watercress - In pond edges
Moist Zone (Berm / Terrace)
The prime planting spots! Benefit from collected water but drain well.
Suggested Plants:
- Fruit trees - Citrus, stone fruit, figs
- Berry bushes - Elderberry, mulberry, goji
- Vegetables - Tomatoes, squash, beans
- Nitrogen fixers - Beans, clover, lupins
- Herbs - Rosemary, lavender, oregano
Dry Zone (Upper Slope / Between Swales)
Still benefits from reduced erosion. Choose drought-tolerant species.
Suggested Plants:
- Native grasses - Deep roots hold soil
- Succulents - Aloe, agave, prickly pear
- Mediterranean herbs - Thyme, sage, santolina
- Pioneer trees - Acacias, carob, olive
- Ground covers - Creeping thyme, sedum
Planting Tips for Success
The Transformation
Bare or eroding slope with water running off
Earthworks in place, pioneer plants establishing, mulch covering soil
Ground cover filled in, young trees growing, soil building
Productive food forest! Fruit, habitat, erosion-free, and water-rich
Your Observations & Predictions
Record your observations and predictions as you explore the simulation.
Your Conclusions
After completing the workshop, summarize what you learned about erosion control.
Instagram Competition
Did you build a swale, terrace, or erosion barrier? Share your photo for a chance to be featured!
Click to upload or drag a photo here
JPG, PNG up to 10MB
Detailed Concepts & Theory
Teaching Suggestions
Age Adaptation
Common Misconceptions
Discussion Questions
Email These Notes
Send yourself a copy of these teaching materials.
Order Workshop Kits
Erosion Challenge Kit
Complete kit with soil samples, miniature slope models, watering can, and plant seeds for hands-on erosion experiments.
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