Effective ways to deal with a potential slope disaster.
Do you ever think about how difficult it is for a landscape architect to plan and design a really contoured site or landscape? Imagine the worst thing that can happen when a high number of steep slopes remain bare and unprotected: High-intensity erosion caused by rain or wind and the unbearable load of the structure above can cause a landslide at any time, destroying everything in its path. Preventing a landslide can be a bit of a challenge.
Protecting the slopes would be the first idea for dealing with a situation like this. So, what can we do to protect a slope?
Here are some slope protection hacks for you to use if you are facing a possible erosion problem.
1. Vetiver grass (Chrysopogon zizanioides)
Chrysopogon zizanioides, well known as Vetiver grass, may be the biggest breakthrough in soil and water conservation in the past few years. The use of a Vetiver grass system can effectively — and at low cost — protect slopes, stop or significantly reduce the risk of slippage, and prevent downstream water contamination. This is because Vetiver grass roots have a high-tensile strength and because when planted on slopes, the grass reduces hydraulic pressure through the removal of water.
WATCH: Vetiver: Green Tech for the 21st Century
The combination of slippage prevention (mass wastage of soil) and the grass’ sediment-filtering ability results in very clean water moving down the catchment. Vetiver grass as been applied in many places all over the world and is getting a good response. This system not only provides a solution to slope protection and soil conservation, but also provides significant economic, environmental, and social benefits by keeping a sustainable environment, as shown in the diagram below.
A Geoweb system provides an economical solution to slope and surface stability problems while meeting a wide range of performance and aesthetic requirements. This system can provide a fully vegetated slope surface that otherwise could not support sustainable plant life.
WATCH: Geoweb slope protection and perforations
The structure has a variety of infill options, including fertile and rich topsoil for vegetation, aggregates from sand, gravel or even larger size rock, and even using concrete of various strength and surface finishes. Geoweb structures can resist down-slope movement of embankment material and anticipate hydraulic flows, control erosion, and increase vegetation stability on slopes.
Old but gold: Gabion structures installation for slope protection may look conventional, but the ability to provide a surface to support plant life and good permeability is just too good to not get attention. Gabion structures have a good flexibility and durability to protect a steep slope.
They can tolerate differential settlement without fracture, which is important on unstable ground, and the durability increases with age as consolidaton takes place: Silt and soil collect in the voids as the vegetation becomes established. The ability to permit the growth of vegetation and maintain the existing environment can provide attractive natural building blocks for decorative landscaping.
4. Bio retaining wall
Nowadays, there are lots of bio retaining wall products with various brand names and prices. Unlike a conventional concrete retaining wall system, a bio retaining wall product made with permeable materials and a variety of surface finishes gives you a lot of choice for your landscaping ideas. More importantly, bio retaining walls come with the ability to support vegetation growth, returning habitat and green space to the built environment while providing structural reinforcement. Aesthetic diversity, temperature moderation, green space, and habitat can all be achieved by using a bio retaining wall system.
You can see samples of bio retaining walls here.
Maybe the simplest idea to protect slopes from erosion is to cover them with ground cover or any vegetation. But growing vegetation on a really steep slope is a really tough challenge; the extreme environment sometimes just feels like it’s impossible to plant. But thanks to hydroseeding, that challenge can be met. Hydroseeding is the process of combining seed, mulch, fertilizer, and healthysoil amendments with water to mix in a HydroSeeder® tank to form a thick slurry.
WATCH: Hydroseeding SaskPower Switching Station – Swift Current, SK
This slurry is applied with pressure to the surface for seed germination and turf development. It gives you a quick, safe, cost-effective, easy-to-apply ground cover, turf, fern, or any other vegetation for your slope’s protection.
Which ever way you to decide to adapt your slope, make sure it fits in with the overall scheme of the site, merging with the design, enviornment and long term purpose. For every situation there is a suitable solution.