 Bridge Protection
 Cascades
 Culverts
 Groynes
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Water has the gift to sustain all life, but also the potential to maim, damage and destroy if not managed correctly. Management of catchment areas requires protection and stabilisation of riverbanks, reducing erosion of slopes, conveyance of water around infrastructure in a controlled manner and the protection of human settlements from the impact of floods.
Longitudinal Structures
Constructed parallel to a watercourse, longitudinal structures correct and control the flow of water preventing flooding of towns and cities, and erosion of stream beds and edges of banks. Longitudinal structures can be classified as light, when simply protecting already stable edges merely from erosion aspects, and heavy when it is necessary to contain the banks.
Weirs and Drop Structures
Installing drop structures or stepped weirs across a steam or river is an efficient means of dissipating water energy over a short distance. The riverbed slope is modified as the flow velocity is reduced allowing suspended solids to settle creating a flatter riverbed slope. Weirs are used as spillways on dams, allowing water to discharge in a controlled manner.
Groynes
Gabion groynes are purpose built structures used for the protection and recouping of eroded banks by deflecting the flow in a watercourse away from the bank. Groynes, constructed some distance into the watercourse perpendicular to the direction of flow, create and form a series of backwater zones that allows for the deposition of the sediment. Anchored into the bank, gabions and Reno mattresses are ideal products for these type of structures where construction is in phases and, in most cases, in water.
Channel Linings
Channel linings are necessary to protect and stabilise the edges of natural and artificial watercourses from erosion. Channel linings take many forms. Gabions, Reno mattresses and erosion control blankets made of either coir or polymer fibre, integrate quickly with the environment. Their permeable and flexible nature can assist in controlling floods, increasing outflow from catchment areas and maintaining and improving ecosystems. These versatile products are easily installed in the presence of water.
Culverts
Structures built from double twist hexagonal wire mesh gabions and Reno mattresses are a valid and effective technical solution in the design and maintenance of culverts and low-level river crossings. In inlet works it is necessary to guide the flows into the culvert, thus avoiding dangerous uncontained flows. In restoration work, one should be aware of erosion of riverbeds and banks which may undermine the structure. In the case of deeply cut watercourses, it is advisable to create structures capable of both containment and support. When the riverbed is not well defined it is good practice to extend the wing walls of the culverts to protect the flanks. At low-level river crossings, where the water flows directly over the roadway, protection is needed both upstream and downstream to prevent erosion which would immediately affect the roadway itself and render it unusable.
Detention Basins
A detention basin is a stormwater management facility installed on or adjacent to tributaries of rivers, creeks or lakes and is designed to protect against flooding and in some cases, downstream erosion by storing water for a limited period of time.
Dams and Spillways
Overflow spillways are constructed as part of embankment dams. The spillway section is lower than the other sections of the dam allowing water to flow over its top and down its front face when the storage capacity of the dam is reached. Due to the steepness of the embankment slopes or the poor limit velocities of the bed material, severe erosion can take place. Reno mattresses or gabion cascade structures are effective ways of reducing those velocities and therefore limiting erosion.
Bridge Protection
Erosion at the foot of the bridge foundations is a serious problem in road engineering. Bridge abutments and bridge piers often collapse as a consequence of scour around and under the foundation from the erosive power of flowing water. Gabions and Reno mattresses provide the ideal protection to the foundation of the piers and abutments and the terrain around the bridge structure. In remote areas, gabions themselves can be used to support the bridge deck structure.
Cascades
The outlet of pipes and lined channels are subjected to critical erosion potential. Stormwater that is transported through man-made conveyance systems at design capacity, reaches velocities that exceed the poor limit velocities of the material within the receiving channel. To prevent scour at the stormwater outlets, cascades protect the outlet structure and minimise the potential for downstream erosion. A cascade structure is needed to absorb the initial impact of flow and reduce the speed of the flow to a non-erosive velocity by means of horizontal aprons and stilling basins.
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