With each passing year, we are losing 1% of our topsoil through entirely avoidable events.
Poor land management practices, climate change, and excessive tillage are just some of the reasons contributing to the 500 million tons of soil eroded annually. Homeowners, gardeners, and lawn care enthusiasts are experiencing the effects of soil erosion through patchy, bald-spotted lawns, weak and pest-infested plantings in their gardens, and clogged pools. That doesn’t even touch the issue for agricultural workers.
And all of this is because of soil erosion. On a hill, soil erosion occurs even faster. Its effects are more devastating and contribute to this global decline.
So preventing soil erosion on a hill or slope goes beyond just an aesthetic complication: it’s an important part of soil quality preservation.
Why Is It So Important To Prevent Erosion On A Hillside?
Soil erosion is the steady and gradual loss of soil to natural elements like wind and rain. In the aftermath of a rainstorm, soil run-off jams up important channels and exposes soil to degradation. When you add gravity to the mix, the harmful effects of erosion occur that much quicker. Soil erosion affects more than your immediate property — it can spell trouble for the entire area.
If residential properties sitting on a hillside or slope don’t take steps to protect their soil from erosion, the effects will resound throughout their neighborhood:
- A loss of nutrients that run off after a rainstorm
- An increase in flooding because of clogged waterways
- A degradation in local air quality because of exposed soils
- Silt build-up at the bottom of driveways
- Clogged neighborhood drainage and storm drains
- Run-off interfering with swimming pools or driveway stability
- Loose soil and mud blocking streams and creeks
- Harm to marine life as well as offspring mortality
There are a few ways to stop hillside erosion. Some are low-tech, some are high-tech — and the method you choose depends on the quality of your property.
Factors To Consider About Your Property’s Hillside
Not all slopes and hillsides are created alike. The topography of the land surrounding your home or building determines which method you’ll use to stop erosion.
Here are a couple of factors to consider:
- The incline: If your slope is less than 33%, you can use mulch to keep your soil secure and cover up topsoil from degradation. Anything greater and you’ll need to consider how accessible your slope is and how much planting you can do.
- Soil make-up: Is the topsoil on your property thin and sit on top of mostly rock? Or is it relatively deep, on a thick layer of subsoil? You need to get a sense of whether covering vegetation can take root and thrive. Keep in mind that sandy soils are more likely to run-off than soils with a clay make-up because the particles in sandy soils are looser.
- Drainage: To measure the drainage on a hillside, you can dig a hole and fill it with water then check back in an hour or two. If there’s no water remaining, natural drainage is good. If the water sits there for two or more days, that means you have rock rather than soil underneath, and may end up with more erosion.
- Bald spots: The presence of bald spots on your hillside property can tell you a variety of things about your soil quality. For example, it may be that the lawn is overly fertilized and poorly irrigated. Bald spots could also be a sign of bedrock right below your soil.
- Sun or shade: If you’re going to be using cover vegetation to secure the soil, you’ll want to make sure that the plantings will thrive in either the sun or shade.
- Irrigation: Is there water easily accessible for your slope? If your hose is on the other side of your property, for example, you’ll need to find a way to water your plantings.
Based on an assessment of these factors, you might find that you’ll need to work with a landscaper or construction specialist. These factors are also a good checkpoint though. They’ll tell you what kind of land quality you’re working with and help determine which of the five ways to stop erosion will work best for your property.
Five Ways To Stop Erosion On A Hillside
Erosion comes in two forms: There’s degradation, which is a gradual erosion of the quality of the soil, and there’s loss of soil particles.
Run-off from heavy spring or summer rainfall is not the only face of erosion — wind can just as easily blow soil particles down a slope. If your hill gets a lot of sun exposure, evaporation can quickly degrade its quality.
To guard against these slow but sure soil eroders, you can use a combination of these five techniques.
1) Build A Garden Terrace
Preventing soil erosion on a hillside is a steep challenge. The incline or rise of the slope makes it prone to a faster rate of landslide and erosion. A compact and elegant solution to this is to terrace your hill. Using homegrown and natural materials, you can put together a series of stages or “terraces” that break up your slope and act as plateaus. This stops run-off from just flowing straight down a hill.
You can then use these stacked terraces or plateaus to plant cover crops and seeds intended to hold the soil together, compact it, and contribute its nutrient content.
Roots from plantings like perennial fruit trees, berry bushes, and herbs are ideal with terraces. They will take to the soil and give it the heft needed to fix it firmly in place. They’ll also contribute nitrogen to the soil, which is the measure of healthy and high-quality topsoil.
The best part is that you can use organic matter to construct and secure the terrace stages. Logs, brush, and wooden stakes are just some examples of the simple but sustainable materials your new terrace garden will need.
2) Use Plantings To Prevent Hillside Erosion
When learning how to stop erosion on a hill, the simplest solution is to use plants. With the right choice of plantings, you can reduce runoff significantly.
Cover crops are extremely effective in:
- Protecting from wind and water erosion
- Increasing water infiltration
- Crafting channels for water flow through the root system
Trees and bushes are especially useful because their roots will go in deep while their leafy canopies will break up heavy rainfall and protect the soil underfoot. Just make sure that your chosen plantings are appropriate for your growing zone. You can also choose groundcover, grasses, legumes, and other broadleaf species to shield your slope.
These plantings multiply generously and quickly, providing a lush backdrop against your hillside. They will be also hearty enough to withstand rain without needing constant pruning and care.
3) Use Sandbags As Diversions
You can’t necessarily fight nature, but you can certainly try to channel and divert it.
That’s what sandbags allow you to do. When heavy rainstorms affect your hilly area, you’ll likely be in the path of other run-off and debris flow.
If this is the case, you can use sandbags as a consistent (though temporary) solution by stacking them in a stair-stepped formation.
It’s temporary because it simply diverts the flow of the water, but doesn’t necessarily seal water off from your property.
It’s a great additional measure to use, especially if your sloped property is just part of a larger, overall hilly area.
4) Build Retaining Walls
Like the terraced gardens, retaining walls are an aesthetic and functional solution, even if they’re a bit more high-tech. Retaining walls allow you to create “zones” or stages to your sloped property, giving it a terraced look.
When pairing it with methods like strip landscaping and using fountains or lawn furniture to mark off these “mini” garden areas, retaining walls can add interest and depth to your sloped property.
These retaining walls hold back soil and create multiple flower and plant beds. You can even get creative and connect them to a set of stairs winding down the hillside to give the effect of a feature path.
5) Use Geotextiles Or Erosion Control Blankets
When examining your property, you may find that there’s a thick layer of rock underneath the soil that won’t support vegetation (yet). You need to build up the thin soil and support it for a few seasons before anything can grow on your slope. That’s when geotextiles and erosion control blankets come in use.
As the name indicates, erosion control blankets cover wide areas of soil on a steep hillside. Some of these blankets are synthetic materials known as “geotextiles.” Others are simple but strong netting crafted from organic material like coconut.
They’re biodegradable and protect your soil from erosion. If you do choose to have plantings one season, they’ll allow the seeds to breathe, take root, and shoot up. Over time, as they break down, they’ll add to the soil’s nutrient content!
With these five methods, you can stop your hillside soil from running off and eroding. There is hope for slopes as long as your methods focus on working with what you already have. And that means working with sustainable and natural options, wherever you can.
What’s good for wildlife is always beneficial for the value of your property and your slope’s stability. Stability is the key to maintaining the quality of soil on a hillside. The greater the level of stability, the less the chance for erosion and run-off. So while you can’t change natural flow patterns, you can use strategic solutions to work with nature.