Water is one of the most powerful forces of nature and despite the numerous benefits and uses it has, it can cause massive destruction. One of the problems caused by uncontrolled water is erosion – a process that removes soil and rocks from the surface of earth due to the flow of water.
It’s an environmental hazard that not only affects water bodies, but landscapes and soil as well.
When rain falls on the earth’s surface, it is either absorbed by the land, evaporated or simply flows across. When water runs downhill, it can pick up sediments and cut the soil forming channels. These eventually merge and form larger streams containing all the sediments passed down. Rivers and streams affect the earth’s surface more than any other form of erosion. Fast flowing water from rivers and streams is one of the principal agents in eroding bedrock and shaping landforms. Without rivers and streams, there would be no valleys and the landscapes would also wear down much slower.
One of the most common ways erosion can affect rivers is by deteriorating the bank and causing the land at the edge to erode. In many areas, native plants have been removed from river banks leaving the soil vulnerable to natural adversities including chronic erosion. Increased erosion can cause an increase of sediments in the river that can lead to several other problems as well.
Hydraulic Works and Erosion Control
Many techniques are used to protect riverbanks. These techniques range from simple re-vegetation to retaining structures on a massive scale. When the motion of water against the surface of rocks produces mechanical weathering, it is referred to as a hydraulic action.
One basic example of a hydraulic action is that of a wave striking the face of a cliff, compressing the air and cracking the rocks. This results in an excessive pressure on the rocks cracking them into smaller pieces. This widens with each wave. The broken pieces lead to two additional types of erosion – abrasion also known as sandpapering and attrition which is similar to the effect of eroded particles in the seabed. In coastal areas, wave hydraulic action is the most common form of erosion.
It has become difficult to avoid flooding due to the development of industries and transportation routes for trade and social exchange. In the rapid age of development and progress, it is also essential to protect the watercourses as they are one of the blessings of nature and a source of survival. Solutions for hydraulic works (which can be viewed in detail at https://www.maccaferri.com/us/applications/hydraulic-works/) must avoid both technical and ethical mistakes and lead to long run stabilisation while promoting the evolution of the ecosystem.
Below are some of the ways of controlling erosion through hydraulic works:
Reno Mattresses
Reno mattresses are used for protecting riverbanks, lining channels, controlling erosion and stabilising riverbanks. At the project site they are filled with rock to form flexible permeable monolithic structures with the aim of promoting growth of natural vegetation. Not only are these mattresses environment-friendly, they easily blend into the structure of the environment by filling gaps in the rock with silt. This maintains an ecological balance by promoting the growth of vegetation.
Another advantage of reno mattress is the flexibility of the woven mesh that allows it to withstand a great amount of load. They are also cost-effective as they can be easily built using standard construction equipment.
Gabion Baskets
In simple terms, gabions are stone filled baskets that are used to prevent soil erosion. They are cylinders filled with earth or stone used in building structures. They are used throughout the world for protecting beds, stabilising banks, retaining walls and several other purposes. Gabion baskets consist of wire mesh filled with cobble or small boulder material. Their thickness is usually between 1.5-3 ft, covering a small area. They are mostly used to stabilise slopes, pipe outlet structures, construct drop structures or for other applications where soil needs to be protected from erosive forces of water.
Waterproofing is also essential for protecting your land from water damage. Some waterproofing solutions include:
Channelling works
This involves constructing a channel with a cross-section that controls winding of a river. They are usually lined in agricultural irrigation schemes that serve various purposes such as reduction of water loss by seepage, stabilising banks, protecting from erosion and controlling the flow capacity of the channel.
Longitudinal Protection
These hydraulic structures have lengths parallel to the river flow and are built on existing natural banks. Some of the purposes they serve include controlling erosion, flood protection and control meandering.
Waterproofing of Reservoirs, Lakes and Channels
Waterproofing ponds and reservoirs help prevent contaminated water from polluting the ground. Waterproofing is done in various areas including slurry ponds, leachate lagoons, storage ponds, reservoirs and storm water attenuation ponds.
Weirs, Culverts and Transverse Structures
Transverse structures help control hydraulic flows that contain sediments and particles by obstructing the flow and reducing the ability to erode. Weirs are used to determine hydraulic profile in areas where bed load transportation and siltation are balanced. It reduces the bed slope and transportation. They are robust and easy-to-install. A culvert constrains the natural flow of the river into a box structure or a man-made pipe.
Water damage issues should be addressed as soon as they occur in order to minimise the damage and loss through waterproofing techniques.
