Introduction to Check Dams: An Erosion Control Practice – RUVIVAL Toolbox

Check-dams, or gully plugs, are structures built across channels
to reduce erosion by lowering water speed and
accumulating sediments during floods. They are often introduced
in degraded areas where natural or agricultural
vegetation cover was lost or not capable of holding the topsoil. Check dams could be grouped into
two main categories: temporary and permanent structures. Temporary check dams include structures
of small to medium size designed to resist a few years. These structures support the
establishment of a permanent vegetative cover and can be removed
when their goal is achieved. Permanent check dams
are medium to large constructions, usually implemented
in severely affected sites. They are designed to last many decades
and to resist massive flood events, usually entire communities benefit from
their implementation. The check dam should be firmly keyed
to the bed and banks of the gully to provide stability
and avoid underflow. Several factors influence
the choice of a check dam, such as topography, precipitation intensity, material and financial resources. Check dams are flexible structures and can be built with a great variety of materials. They can be built with brushwood, wooden posts, stones, fixing gabions, cement or simply by piling sandbags. Check dams
need to be built on the right places, ideally where water can be directed to
suitable areas for groundwater recharge. In this sense, locations where natural
vegetated floodplains exist are particularly suitable. Check dam implementation
needs to be started in the upstream of a catchment, in order to avoid the destruction
of the downstream structures. Furthermore, suitable land use, humus building and terracing should accompany the first aid of the plugs. The variety of materials and resources
that can be used to make check dams, makes them a flexible and suitable solution for different areas and environments. They are also one of the most used
stabilisation measures worldwide. However,
a drawback is the constant
and intense maintenance needed: if not accomplished,
incompleteness of the work and improper maintenance can in
fact lead to structural damages with time. The higher frequency of heavy floods
due to climate change forces constructors to pay more attention to the after implementation phase
of a check dam: the maintenance. This is to avoid subsequent
collapses and failures. It is essential to adapt check dam design
to changes in context, climate and situation, and integrate post-completion
supporting structures and to implement
continuous maintenance practices.

2 thoughts on “Introduction to Check Dams: An Erosion Control Practice – RUVIVAL Toolbox

  1. Great one…
    We need more mechanical structural for erosion control and design…

Leave a Reply

Your email address will not be published. Required fields are marked *